Early thinking palliative care for people with Parkinson's disease: A thematic synthesis based on a systematic mixed-methods review

Abstract

Background

Parkinson's disease is a progressive neurodegenerative disorder. Awareness and the evidence supporting the merits of palliative care (PC) approaches to people with Parkinson's disease (PwP) are increasing.

Objective

This review aimed to address four key questions related to PC for PwPs and their caregivers: i) What are the indicators for timely access to PC? ii) When should PC be introduced? iii) What are the current care models for providing PC? iv) What are the barriers and facilitators at the organizational level?

Methods

A systematic literature search was conducted in PubMed, CINAHL, Cochrane, EMBASE, and MEDLINE (2006–2024). Six reviewers independently screened abstracts and full texts, and thematic synthesis was applied to develop analytical themes. Reporting followed PRISMA guidelines.

Results

Out of 894 studies, 70 were included. PwPs were infrequently referred to PC services, and while several referral criteria were identified, no consensus emerged. Barriers to accessing PC included insufficient information, inadequate education, difficulties determining referral timing, limited home-based care options, inconsistent provider support, and disparities linked to socioeconomic and cultural factors. Facilitators included improved care coordination and education for PwPs, caregivers, and healthcare providers. Effective PC models were identified, including home-based, hospital-based, and community-based approaches, which improved quality of life and reduced healthcare costs.

Conclusions

Establishing consensus on referral timing and criteria is essential for integrating PC into Parkinson's disease care. Overcoming barriers requires enhanced education, better care coordination, and targeted interventions to address disparities, ensuring comprehensive, patient-centred care for PwPs and their caregivers.

Introduction

The World Health Organization (WHO) defined palliative care in 2002 as a holistic approach aimed at improving the quality of life for patients and their families facing challenges associated with life-threatening illnesses. ¹ However, numerous economic, social, legal, cultural, and health policy barriers hinder the early implementation of palliative care (PC) in neurology, particularly for people with Parkinson's disease (PwP) and related disorders.^2–4 Despite growing awareness and an expanding body of research on PC, several factors continue to obstruct its integration into clinical practice.

First, PC remains a linguistically and conceptually misunderstood term, often equated with end-of-life or terminal care, even among healthcare professionals (HCPs). ² Governments have been hesitant to invest in PC services due to uncertain implementation timelines, limited supporting evidence, and a lack of consensus on planning strategies. ⁵ Furthermore, access to educational programmes at both basic and specialist levels remains insufficient. Surveys reveal that only a small proportion of HCPs have received PC training specific to managing PwPs.^6,7 This lack of training undermines the availability and quality of specialized PC for PwPs, as untrained HCPs are often ill-equipped to address these needs and may undervalue the benefits of PC. ⁸

Existing PC models, predominantly developed in Western healthcare systems, lack adequate racial and ethnic diversity in their design and implementation. ⁹ Socioeconomic status, race, and ethnicity have been associated with decreased PC engagement and a higher likelihood of aggressive end-of-life treatments, highlighting significant disparities in access and outcomes.^9–12

Although PwPs experience substantial morbidity and mortality and evidence increasingly supports the benefits of early PC integration, their PC needs often remain unmet.^13,14 PwPs frequently report traumatic diagnostic experiences, insufficient management of non-motor symptoms, and inadequate hospice care planning, often leading to institutionalized deaths. ¹⁵ Recognizing the critical role of PC in managing Parkinson's disease (PD) and enabling timely access to it through advance care planning (ACP) is essential. ¹⁶ ACP, a patient-centred approach, ensures care aligns with the patient's autonomy, wishes, and decision-making capacity. ¹⁷

Recent studies have explored specific aspects of PC, such as indicators for its provision, caregiver experiences, and ACP.^16,18,19 However, PC is not solely about end-of-life care. Early integration of PC addresses physical, emotional, psychosocial, and spiritual needs, fostering a patient-centred care approach. Sharing care preferences effectively with relatives, partners, and HCPs ensures these preferences are respected when patients can no longer communicate their wishes.

This study aims to map the current research landscape to understand how early integration of PC for PwPs can be achieved. Four research questions guide this investigation, focusing on both PwPs and their caregivers:

1. What are the indicators for timely access to palliative care?

   This question identifies starting points for integrating PC into the care pathways of PwPs at an early stage.

2. When should palliative care be introduced?

   This involves determining clinical criteria, such as disease status or symptom severity, that inform the timing of PC.

3. What are the current care models for providing palliative care?

   This question examines existing approaches to PC delivery for PwPs.

4. What are the barriers and facilitators for providing palliative care at the organizational level?

   This explores organizational aspects, including intra- and inter-organizational factors and interactions with individuals, that influence access to PC for PwPs.

Methods

A systematic mixed-methods review ²⁰ of the published literature on palliative care for PwPs was conducted, with its protocol registered in PROSPERO (PROSPERO 2021 CRD42021254848). The review adheres to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, and the PRISMA 2020 Checklist is provided in Supplemental Material 1.

Search strategy

Peer-reviewed articles published in English between January 1, 2006, and May 31, 2021, were retrieved from PubMed and via OVID to access CINAHL, Cochrane, EMBASE, and MEDLINE. The literature search was conducted in May 2021 and updated in December 2022 and March 2024. Additional studies were identified through manual forward and backward citation tracking. The timeframe was chosen because, in 2006, the World Health Organization issued a policy document highlighting the public health challenges and impact of neurological conditions. ²¹ The full search strategy is provided in Supplemental Material 2.

Eligibility criteria

The inclusion and exclusion criteria for study selection were developed using the PICO (Population, Intervention, Context, Outcome) framework. The following eligibility criteria were applied:

• Participants: People with Parkinson's disease or atypical parkinsonian syndromes, their caregivers, and/or healthcare professionals. There were no restrictions regarding the type of Parkinson's disease, age, or gender.

• Intervention: Any introduction, application, assessment, or intervention related to palliative care for PwPs.

• Comparator: Not applicable.

• Context: All healthcare settings (place of residence or institutions) and all levels of care (primary to tertiary).

• Outcomes: Outcomes for PwPs related to PC.

• Design: Empirical studies, with no restrictions on study design or data characteristics (e.g., quantitative, qualitative, or mixed methods).

Only studies published in English were considered. Preclinical studies, conceptual papers, review articles, books, book chapters, book reviews, conference proceedings, editorials, national guidelines, dissertations, and all non-peer-reviewed publications were excluded. No geographical restrictions were applied.

The inclusion criteria were further refined based on the specific research questions (RQs):

• RQ 1: Studies were included if they identified indicators for timely access to palliative care, with at least one suggestion for early integration into the care pathway.

• RQ 2: Studies were included if they examined indicators and needs for palliative care referral for PwPs and their caregivers, encompassing the experiences of PwPs, caregivers, and healthcare professionals. Inclusion required at least one indicator (e.g., a clinical marker) of when referral to palliative care was appropriate.

• RQ 3: Studies were selected if they evaluated at least one current or new model of palliative care for PwPs.

• RQ 4: Studies were included if they addressed at least one barrier or facilitator affecting the implementation of palliative care for PwPs from an organizational perspective. The organizational perspective was defined according to Ansmann et al., ²² encompassing:

  • Conditions under which care organizations operate and their interactions at individual and organizational levels.
  • Structures, processes, and cultures of healthcare organizations.
  • Interactions within and between care organizations.
  • The impact of these factors on healthcare outcomes and organizational performance.

Selection process

Search results were imported into the review management tool Covidence (Covidence—Better Systematic Review Management, www.covidence.org), where duplicates were removed. The study selection process followed a two-stage screening procedure: the first stage focused on titles and abstracts, and the second stage involved a detailed examination of full-text articles. Two independent reviewers (V.L. and G.G.) conducted the screening of titles and abstracts and retrieved full-text articles for detailed review. Any conflicts were resolved by a third independent reviewer (P.P.).

The full texts of all included studies were independently screened by two of the six reviewers (B.W.D., C.M., C.W., D.T., M.G., P.P.), who decided on inclusion or exclusion based on the predefined criteria. In cases of disagreement, a third reviewer from the group was consulted. The selection process is summarized in a flow diagram presented in Figure 1.

Figure 1.

PRISMA flow diagram.

Data items

The extracted data from the included reports covered the following items: first author, year of publication, country, study design, number of participants and their clinical characteristics. In addition, specific elements were extracted according to the research question, i.e.,

RQ1: Indicators for timely access to palliative care

RQ2: Indicators for palliative care referral (when), palliative care needs (physical, social, psychological, spiritual, informational)

RQ3: Study design and/or care models, use of care, healthcare providers involved, care coordination between healthcare providers, frequency of visits and place of visits, evaluation of palliative care model

RQ4: Hindering factors, facilitating factors

Risk of bias in individual studies

To evaluate the extent to which potential bias was addressed in the design, conduct, and analysis of the included qualitative and quantitative studies, the Quality Assessment Criteria for Evaluating Primary Research Papers from a Variety of Fields (QualSyst) ²³ were applied. Two reviewers, selected from a group of five (M.G., B.W.D., C.M., C.W., and P.P.), independently assessed the risk of bias. Any disagreements were resolved through discussion, and in cases of irreconcilable disagreement, a third reviewer was consulted.

Thematic synthesis

The data were analyzed using thematic synthesis. ²⁴ The process involved the following steps: Firstly, two reviewers prepared the extracted data for analysis. The data were organized into structured tables in Microsoft Word, tailored to address the four research questions. Secondly, a combined table was created for research questions 1 and 2, as there was significant overlap in the content. Separate tables were created for research questions 3 and 4 to maintain clarity and specificity. Thirdly, we identified the themes. First, descriptive themes were initially extracted from the literature, closely adhering to the body of evidence presented in the studies. Second, analytical themes were then grouped and refined into seven broader analytical themes through iterative group discussions among the reviewers. Finally, any discrepancies in theme identification or categorization were resolved through a consensus process involving all reviewers. This structured approach ensured that the thematic synthesis was thorough, transparent, and directly aligned with the research questions (Supplemental Material 3).

Results

Study identification and selection

A total of 894 records were retrieved, of which 252 were retained after excluding duplicates and non-relevant papers. Subsequently, 203 records were excluded for not meeting the inclusion criteria. Following the initial search and screening process, 49 reports were included. The first update added 7 articles, and the second update contributed an additional 14 articles, bringing the total to 70 publications comprehensively evaluated for this study.

For the research questions:

• 12 reports were included for research question 1,

• 22 for research question 2,

• 40 provided additional information on the palliative care needs of the population, resulting in a total of 47 included publications,

• 32 reports were considered for research question 3,

• 17 for research question 4.

It is important to note that some reports contained relevant information applicable to multiple research questions (see Figure 2).

Figure 2.

Flowchart depicting the article inclusion process for thematic analysis.

Study characteristics

The majority of the articles originated from the United States (49%), followed by the United Kingdom (13%). The studies comprised quantitative studies (47 out of 70, 67%), qualitative studies (17 out of 70, 24%), mixed-method studies (4 out of 70, 6%), others (2 out of 70, 3%). A detailed overview of the characteristics of the included studies is provided in Tables 1–4.

Table 1.

Studies presenting indicators for timely access to palliative care and when it should be addressed for PwP and their caregivers.

First author (year) country	Number of participants; mean age; percentage women	Study design	Palliative care needs (physical, social, psychological, spiritual, informational) (RQ2)	Indicators for timely access to palliative care (RQ1)	Indicators for palliative care referral (when) (RQ2)	Quality assessment rating (QualSyst)
Akbar (2024) USA 37	Population: Survey 1: n = 34 medical directors and coordinators at 34 Parkinson's Foundation Centers of Excellence (COE); Survey 2: n = 667 HCPs before an online course on team-based palliative care offered through the Parkinson's Foundation education platform; Survey 3: n = 371 patient-facing HCPs at COE 164 physicians: 43.6 (11.1) years old, : 48% women; 35 nurse/RN; 44.1 (14.0) years old, 97% women; 29 Social workers: 42.1 (13.2) years old, 93% women; 27 APPS: 42.6 (10.0) years old, 96% women; 116 other professionals: 44.0 (13.2) years old, 83% women	Quantitative study, national surveys: survey 1 (to explore available PC services and resources); survey 2 (knowledge of palliative care and attitudes/experiences with PD); survey 3 (perceptions of PC and current PC practices)	–78% of physicians reported that <50% of their patients had moderate to high PC needs.		–General agreement among HCPs that people with advanced stage PD should receive PC at the COE, only 28,3% of physicians and APPs thought it was appropriate for all PwPs.	95%
Alvarez Sauco (2023) Spain 68	Population: n = 58 neurologists, age ranges (n, %): –30–40 (15, 25.9) –41–50 (22, 37.9) –> 50 (21, 36.2) No information on gender	Descriptive, observational, cross-sectional study survey	-	-	Referral criteria to PC: –malnutrition/eligibility for feeding by percutaneous endoscopic gastrostomy –pneumonia –recurrent hospitalizations in the previous year –severe ulcers	85%
Badger (2018) 54 UK	n = 3 PwPs; n = 5 PD caregivers, age range from 61 to 79 years old; 75% women	Qualitative study, semi-structured interviews, interpretative phenomenological analysis	–Cope with: advanced Parkinson's disease/ uncertainty/ impact on the self/maintaining a positive outlook [psychological]	-	-	93.75%
Bock (2022) 84 USA and Canada	Intervention n = 106 PwPs; 70 years, 39% women n = 87 caregivers; 66 years, 71% women Control n = 104 PwPs; 71 years, 33% women n = 88 caregivers; 66 years, 75% women	Randomized controlled trial	–Improvement in their feeling about their self as a whole [psychological] –Improvement in anxiety, well-being, shortness of breath, stiffness, confusion, hallucinations and total symptom burden were significantly correlated with improved patient QOL [physical, psychological] –PwPs spiritual well-being, decreased patient anxiety, decreased patient depression and decreased grief correlated significantly with increases in QOL [psychological, spiritual] –Improvement in PwPs anxiety correlates with decreased partner burden, decreases in PwPs and care partner anxiety and depression correlated with decreased care partner burden, increased partner spirituality correlated with decreased care partner burden [psychological, spiritual] –Completion of advance directives correlated with a small improvement in care partner burden [social]	-	-	100%
Bock (2024) USA 50	n = 28 PwPs, 73.71 (6.96) years old, 36% women ; n = 33 caregivers, 67.24 (10.52) years old, 86% women	descriptive qualitative study embedded in a pragmatic, multisite, randomized controlled trial of community-based palliative care.	–Participants expressed the concern that their neurological care is overly focused on motor symptoms and medications, lacking in understanding about the full spectrum of care needs [psychological, social, spiritual] –Participants expressed the desire for anticipatory guidance about the disease course, even if the predictions are imperfect. [informational] –Participants described their care team as consisting of themselves and physicians, with few mentions of other HCPs. Lack of team-based care [psychological, social, spiritual] –Desire for counselling, mental health support to address mood symptoms and help processing the changes. [psychological] –Participants are frustrated by inaccessibility of their primary neurologist and lack of communication between physicians [informational]. Need for care partner to serve as care coordinator [social].	-	-	95%
Boersma (2016) 26 USA, Canada	n = 30 PwPs; 68.1 (7.1) years; 37% women n = 11 PD caregivers; 65 (8.2) years; 82% women	Qualitative study, inductive analysis of individual interviews	–Education to PwPs, particularly on what to expect in the future. (through internet-based materials, group classes, community based resources, and patient mentoring programmes). [informational]	–A part of PwPs were supportive of team-based care and early palliative care, particularly at the time of the diagnosis and with disease progression.	-	60%
Boersma (2017) 58 USA/Colorado	n = 11 PD caregivers; 65.8 (8.2) years; 81.8% women n = 11 PwPs; 65 (5.9) years; 18.2% women	Qualitative study, semi-structured interviews, inductive analysis	–Caregivers: individual attention and support, separate needs from patients. [psychological] –Educational needs about disease progression and helpful resources for understanding PD [informational] –counselling [informational] –resources for themselves [social] –Guidance on behavioural issues [informational]	-	–In advanced disease stages, as they require a higher level of care.	60%
Bruno (2016) 70 Canada	n = 52 PD caregivers; No information available about age and gender of participants.	Quantitative observational study	-	-	–Criteria to be admitted in the Palliative care clinic: –  – H&Y stage 3 or higher –  – dementia –  – psychosis –  – significant caregiver strain	86.4%
Fleisher (2020) 67 USA	n = 27 PwPs; 80.9 (7.8) years; 36% women	Quantitative study, single arm, monocentric pilot trial	–Clinical care possibility for home bound PwPs [social]	-	–Movement disorders specialists referred patients to study: if they missed >1 recent appointment or had been hospitalized or temporarily institutionalized in the preceding year. Leaving the home “required a considerable and taxing effort”, and was either contraindicated or required the use of assistive devices, assistive transportation, or the aid of another person. –To further identify individuals at risk for hospitalization, patients needed to have >1 of the following criteria: motor fluctuations, multimorbidity, medication mismanagement, mild cognitive impairment, depression, anxiety, recent increased falls, or suspected elder abuse, neglect, or caregiver burnout.	85%
Fox (2015) 6 Ireland	n = 306 health care workers No information available about age and gender of participants.	Quantitative survey with some open-ended questions	–reasons for SPC referral: symptom control pain management benefit from expert or specialist care [physical, psychological, social, informational]	-	–Symptoms listed in order, that are seen as most troublesome for patients: pain; immobility; swallow/feeding difficulties; psychological (e.g., depression); communication; rigidity; dementia/cognitive changes; respiratory problems; tremor; and constipation.	80%
Fox (2016) 25 Ireland	n = 30 health care workers; 87% women	Qualitative, exploratory, inductive research design, using one-to-one in-depth interviews.	–Quality of life, comfort care, holistic care [psychological, social, physical, spiritual]. –Need for professionals’ education on neuro-palliation. [informational]	–Introduction of the palliative care concept since the diagnosis.	–Episodic involvement of SPC teams throughout the illness is preferrable. –In advanced PD, for conditions such as aspiration pneumonia, swallowing difficulties. –In dealing with complex cases involving ethical dilemmas or complex discharges. –“Triggers for referral” to SPC: when Quality of life of the patient is declining –considering PEG (percutaneous endoscopic gastrostomy) feeding –not able to manage the symptoms disease duration is around 10–15 years or advanced stages drugs aren't working anymore –dementia requires earlier conversations around SPC and advance care planning.	75%
Fox (2017) 36 Ireland/Cork	n = 19 PwPs; 67.9 (8.2) years; 32% women n = 12 PD caregivers; 68.2 (6.6) years, 92% women	Semi Structured qualitative interviews, thematic analysis	–Individualized information and support needs [informational] –Extra support in crisis time [psychological] –Participants experiencing advanced illness welcomed any specialized support, including help with anxiety, breathlessness, fatigue or other issues affecting quality of life [physical, psychological].	-	–Key ‘crisis times’ for extra support and/or SPC. involvement were identified, namely, at diagnosis and when illness is advancing (when medications are becoming less effective).	60%
Fox (2020) 57 Ireland/Cork	n = 29 PD caregivers <40 – >80 years (age range); 83% women	Quantitative cross sectional survey	–Assessment and management of carers’ palliative care needs, including anticipatory grief, must occur regularly [psychological, social, informational]	-	–Anticipatory grief was more common among carers of a loved one with PD experiencing hallucinations, repetitive questioning, and agitation; –more advanced disease stage was associated with higher carer anticipatory grief.	95%
Giles (2009) 60 Canada	n = 3 PwPs 71–77 years; 67% women n = 4 PD caregivers 36–75 years; 75% women	Qualitative study, exploratory phenomenological investigation	–Information regarding prognosis, diagnosis and homecare services. [informational]	-	-	85%
Goy (2008) 45 USA/ Oregon	n = 47 bereaved caregivers; 68 (14.1) years; 76.6% women n = 47 PwPs; 78 (8.1) years; 21.3% women	Quantitative cross-sectional survey	–Caregivers: they did not feel prepared to cope with the stress of caregiving, the extensive physical needs of the patient and the related emergencies. [psychological] –Need for more efficient communication with health care professionals about treatments, side effects and prognosis, especially when the patient is cognitively impaired. [informational] –Hospice workers do not have enough information about PD at the end of life to adequately prepare families for this period. [informational]	-	-	66.7%
Goy (2008) 61 USA	n = 52 caregivers; 67 (13.7) years; 76.9% women n = 52 PwPs; age at death 78 (8.1) years; 11% women	Quantitative cross-sectional survey	–Fix goals of care [social], –Symptom control (e.g., pain) [physical];	-	-	81.8%
Goy (2015) 71 USA	n = 339 PwPs; age of death 80 (6.6) years; age PD first noted 73.7 (6.8) years; 2% women	Quantitative cross-sectional survey	-	-	–Indicators for hospice referral (indicators 6 mo. before death): below-normal weight (when weight at 30–36 mo. before death was normal) and/or a decrease to two or less dopaminergic agent prescriptions.	100%
Hasson (2010) 56 UK	n = 15 bereaved PD caregivers; age range from 55 to more than 65 years; 27% women	Qualitative exploratory descriptive study	–to be better prepared for the advancement of the disease. [informational] –Bereavement support should be available to all who need it, also before death. [psychological] –regular surveillance of the patients’ needs by specialists. [psychological, physical, social, informational]	-	–Physical and psychological deterioration of the PwP.	90%
Higginson (2012) 46 UK	n = 82 PwPs; 67 (8) years; 56% women	Quantitative longitudinal study	–symptom burden (problems using legs, fatigue, pain, difficulty in communicating, mouth problems, use of arms and hands, spasm/stiffness, sleep problems, difficulties in bladder control, problems swallowing, shortness of breath) [physical]	-	-	100%
Hudson (2006) 48 Australia	n = 35: 8 PwPs, 21 family caregivers, 6 professionals. PD: 50% women; family caregiver: 72% women; Professionals: no gender available	Qualitative descriptive study, semi-structured interviews	–Experiences and needs that are similar to usual palliative care populations [informational] –Emotional impact of diagnosis- feeling of grief–Loss and uncertainty [psychological] –Monetary difficulties [social] –Immobility [physical] –Exhaustion of caregivers [social] –Psychological and Social isolation [psychological and social]	-	-	85%
Jensen (2022) 42 Germany	n = 87 physicians (45 GPs and 42 neurologists); 53.5 (9) years, 41.4% women	Quantitative study (monocentric, cross-sectional, observational study)	–Physicians: provision of information on swallowing disorders and dysautonomic symptoms is important [informational].	–early consultations to discuss and write a PD-specific AD as important in order to include people with in the decision-making. –early communication about possible neuropsychiatric symptoms and their treatment is important. However, they did not want to scare PwPs in the early course of the disease.	–57,7% of the physicians considered the value of advanced therapies for a palliative care approach rather important.	100%
Jordan (2020) 62 USA, Canada	n = 30 PwPs; 66 (8) years; 37% women n = 30 caregivers; 68 (7) years; 77% women	Qualitative descriptive study, secondary analysis from interviews from a randomized controlled trial	–Future planning and information about illness trajectory, such as a roadmap. [informational] –Guidance around life changes that are related to ethical and legal issues (financial planning needs, safety concerns), and cultural aspects of care (navigating medical systems and care partner role changes) [informational] –clinicians: to assess readiness to engage in topics as progression, future planning and mortality in a tailored and honest fashion. [informational]	-	-	75%
Klietz (2018) 39 Germany	76 PwPs; 75 (6.1) years; 53.9% women	Quantitative, descriptive cross sectional study	information concerning palliative care, especially about advance care planning concerning end-of-life care [informational]	-	-	90%
Klietz (2020) 43 Germany	n = 30 experts finished first Delphi round, n = 22 finished the survey, 40.2 ± 10.4 years; 36.7% women.	Delphi Process	–Consensus on specific advance directives recommendations for PwPs [informational]	-	-	70%
Kluger (2019) 13 USA	n = 90 PwPs; 67.6 (9.1) years; 29.9% women	Quantitative study cross sectional observational study	–High symptom burden [physical], –poor spiritual wellbeing and grief. [psychological]	-	-	100%
Koljack (2022) 55 USA and Canada	PwPs and related disorders N = 175 PwPs and caregivers N = 147 usable completed dyads PwPs N = 146 usable dyads caregiver N = 134 combined usable dyads PwPs: 70.8 (8.2) years 32.1% women; caregivers 66.6 (10) years, 71.6% women	Explorative cross sectional analysis of baseline data from a larger RCT of outpatient palliative care (Kluger 2020)	–PwPs: motor symptoms, health related quality of life, overall performance status, faith and grief are possible contributors to PD caregiver spiritual well-being or distress [psychological, spiritual, physical] –Caregiver: anxiety and depression are possible contributors to PD Caregiver spiritual well-being [psychological, physical, spiritual]	-	-	95%
Kundrick (2023) USA 31	Population: n = 106 PwPs, 71 (8.4) years old, 46% women	Quantitative study, national survey	–Informational needs about PC, the neurologist should initiate the conversation. [informational]	–A third of respondents felt that ACP should be discussed early in the disease course	-	94%
Kwok (2020) 47 Asia	n = 186 PwPs; 67.2 (8.1) years; 54.3% women	Quantitative cross-sectional study	–psychosocial, physical (related to pain) needs and other symptoms at the early to middle disease stage [physical, psychological]. –information needs were also reported [informational] –physical needs related to pain were associated with advanced disease staging [physical]	-	-	100%
Lennaerts (2019) 32 Netherlands	n = 10 individual interviews with health care professionals; ranging from 25 to 64 years; 70% women 3 focus groups with healthcare professionals (n = 29); ranging from 25 to more than 65 years; 90% women	Qualitative descriptive study	–Speaking timely about needs [physical, psychological, social, spiritual, informational] –Guidance and evidence for disease management in PD as for legal implications of end-of-life decisions (i.e., feeding tube placement) [informational] –Professionals need for training [informational] –Need for a central figure in palliative care for PD (i.e., a case manager). [social]	–Early involvement of ACP discussions before cognitive impairment occurs.	-	90%
Lennaerts-Kats (2020) 27 Netherlands	n = 10 health care professionals; ranging from 25 to 64 years; 70% women 3 focus groups with healthcare professionals (n = 29); ranging from 25 to more than 65 years; 90% women	Mixed methods, individual and focus group interviews, three-round modified Delphi study	–Realistic conversation about disease stage, prognosis, possible therapeutic options and disadvantages of proposed treatment. [informational]	–Palliative care starts at the time of the diagnosis, but not always can be appropriate. –Discussions about future care and care goals should be initiated timely, before cognitive impairment or communication problems arise.	–Indicators for ACP: At least two of them: signal or requests for ACP/EoL discussions, lose hope or dreads the future, frequent falls (resulting in hip fracture for example), dysphagia or pneumonia episode, cognitive deficits/neuropsychiatric problems, unplanned hospital admission. –Indicators to identify palliative care phase onset: At least one of them: goal of care moves towards maximization of comfort, transition in care needs (recurrent hospital admissions, nursing home admissions, increase in ADL support), PD drug treatment less effective or increasingly complex regime of drug treatments, several specific PD symptoms/complications (weight loss, recurrent infections, progressive dysphagia, neuropsychiatric problems and/or multiple falls). –When there are not many medical options anymore.	95%
Lennaerts-Kats (2020) Netherlands 34	N = 10 bereaved caregivers, 44–81 years, 80% female	Qualitative study, semi-structured interviews, interpretative phenomenological analysis	–Caregivers feel like professional caregiver, they have to overtake many roles and tasks [social, psychological], are on their own [social], are behind the times [informational], HCPs not always know what PD really means [informational],	–Willing to be engaged earlier in discussions about future care and treatment options, before cognitive deficits or communication problems arose	-	100%
Lennaerts-Kats (2022) 53 Netherlands	PwPs and family caregivers: N = 10 patients; median 77 years, ranging from 68 to 82; 60% women N = 8 PD caregivers; 75 [52–84] years 12%women	Mixed methods case study	–Fatigue, sleep difficulties, communication issues, falls and freezing were the symptoms described as common and distressing aspects [physical] –Social isolation due to adherence to medication schedules and others did not like to be confronted with advanced PD [social] –Fear of the future [psychological] –Difficulties in obtaining access to various medical services [social] –Sufficient time during doctor-patient conversations especially when end-of-life issues were addressed [informational] –Wish for honest and open conversations on their current and future health situation [informational]. –Caregiver burden: numerous everyday tasks and arranging, coordination, organization of healthcare, without little support from health care professionals [informational, social, psychological] –Need for more information about what was available for them in forms of information or professional healthcare [informational] –Wish for timely discussion about prognosis, future symptoms, medical treatment and reimbursement [informational] –Need for information about medical options for advanced PD, options of palliative and supportive care [informational] –Wish to hasten death [spiritual]	-	-	90% (Quant); 85% (Qual),
Lex (2018) 64 Austria	n = 9 PwPs; age range 59–94 years; 56% women	Qualitative semi-structured ethnographic interviews	-	-	–Reliable and validated PD and palliative care assessment instruments could not be adequately used in patients’ late stages.	45%
Lum (2019) 33 USA	n = 30 PwPs; 66 (8) years; 37% women n = 30 PD caregivers; 68 (7) years; 77% women	Qualitative descriptive study within a multisite, randomized clinical trial	–information about ACP and their content. [informational] –physician support for the ACP process [informational]	–Timely ACP conversations can lead to benefits: acknowledging the future PD-related changes can result in focusing on ways to maximize their current quality of life (given the uncertainties about future decline).	–Palliative care approach was helpful for the patients for the integration of ACP conversation in the routine and for the involvement in those of multidisciplinary team members.	90%
Macchi (2020) 66 USA	n = 175 PwPs; 70.7 (8.1) years; 29.1% women n = 175 PD caregivers; 66.1 (11) years 73.1% women	Quantitative study, cross sectional randomized trial	–Interventions to alleviate caregiver mood disturbances and burden [social].	-	–PwPs have high palliative care needs for much longer than their last 6 months of life.	90.9%
Mahes (2024) USA 72	n = 301 PwPs and related disorders n = 34 community based neurologists, PDPR: 74.7 (8.2) years; 32.89% women; neurologists: 44.97(8.87) years; 61.76% women;	Secondary analysis of data collected in a RCT	-	-	–12 months surprise question may be helpful in identifying patients for PC referral, only moderately accurate in predicting 12-month mortality.	95%
McLaughlin (2011) 49 Northern Ireland/UK	n = 26 PD caregivers; aged over 55 years; 65% women	Qualitative semi structured interviews	–knowledge about PC services [informational], Misconceptions hospice care synonymous with cancer [informational] –Respite care [social] –Financial burden [social]	-	–“as condition progressed”, burden for caregiver enormous (financial, emotional, social).	80%
Miyasaki (2012) 63 Canada	n = 190 PwPs with at least one assessment, n = 65 PwPs with more than one assessment; mean age 68 (46–80) years;	Quantitative longitudinal study	–ESAS PD practical to administer in advanced PD care, useful in identifying symptoms not typically elicited in routine care;[physical] –Advanced PD patients have a similar degree of symptoms as metastatic cancer patients [physical]	-	–ESAS-PD can help practitioners identify symptoms requiring intervention	73%
Prizer (2020) 51 USA	n = 175 PwPs with caregiver; 70.7 (8.1); 29.1% women n = 35 PwPs without caregiver; 67.1 (8); 68.6% women	Quantitative exploratory cross sectional study	-	-	–When moderate to high palliative care needs are present as assessed by the Palliative Care Needs Assessment Tool (PC-NAT) modified for PD.	100%
Prizer (2020) 52 USA	n = 75 PwPs for the survey; completed n = 49; 66.4 (10.4) years; 40% women; n = 23 for the qualitative interviews; 66.2 (10.1) years; 43% women; n = 62 physicians; 45 (10.4) years; 40% women	Mixed method study (quantitative survey and qualitative interviews)	–PwPs reported psychological needs as being the least met, followed by physical, social, spiritual, and financial need. [physical, psychological, social, spiritual] –more effective care coordination across the health care system, since it's a burden that often fell on them. [social] –instructions or education from health care providers for managing their care. [informational] –neurologist: to embrace a more holistic approach when dealing with PD, addressing needs other than just medications. [psychological, social, informational]	-	-	95.5% (Quant); 90% (Qual)
Richfield (2022) 59 UK	n = 50 PwPs, men: mean age 73 years, ranging from 59 to 86 ; women: 76 [60–89] years; 48% women n = 28 carers No information available about age and gender of carers.	Mixed method study (qualitative interviews and quantitative psychometric testing of a tool)	–The constructs and items of motor and non-motor symptoms of the NAT: Parkinson's disease scale were expanded to reflect the symptoms’ prominence and distress in PwPs [physical, psychological]. –The section of health beliefs was altered to highlight the difficulty in perception of palliative or hospice care in PwPs and their carers [informational] –The information section was adapted to reflect the difficulties associated with information management, with prompt to the prognosis, which is poorly understood [informational] –Challenges related to spiritual and existential impacts of caring were added [spiritual, social]	-	-	80% (Quant); 60% (Qual)
Saleem (2013) 30 UK	n = 82 PwPs; 67.1 (8.8) years; 45.1% women	Quantitative cross-sectional survey	–high in people with advanced PD (H&Y from 3 to 5), as is the burden caused by symptoms and concerns. [physical, psychological]	–Routine assessment of symptoms in PD could aid timely referral.	–Increasing disability or disease progression could serve as a trigger for referral.	100%
Seshadri (2023) USA 19	n = 1266 PwPs, 71.4 (7.9) years old, 60% women n = 616 caregivers, 70.1 (8.5) years old, 84% women	Electronic national survey	–Support for the management of non-motor symptoms [physical, psychological] –Pain is the most difficult and least addressed non-motor symptom [physical] –Participants’ grief, guilt, sadness or spiritual concerns are not addressed in the 50% of cases. Even more rarely they are connected with chaplains or counsellors. [psychological, spiritual] –Caregiver needs and well-being are occasionally enquired, but additional support for caregivers was rarely provided. [psychological] –Anticipatory guidance was rarely provided, and two-thirds of PwPs and caregivers reported that their physician never completed any ACP documentation [informational].	-	-	100%
Seshadri (2024) USA 29	n = 23 PwPs, 69.5 (8.14) years old, 26% women; n = 24 caregivers; 68.88 (9.93) years old, 71% women	Qualitative descriptive research design, semi-structured interviews	–non motor symptoms are the most challenging aspect of PD –PwPs want neurologists to routinely assess and provide ways to manage non motor symptoms [psychological, spiritual, physical, social] –PwP's grief, demoralization and emotional issues are not addressed [psychological] –caregivers want guidance for management of non-motor symptoms and their wellbeing in a dedicated space [physical, psychological, social]. Participants want more knowledge and guidance about PD [informational]	–Some participants wanted ACP discussions immediately after the diagnosis; while others early on, with follow-up over time. –The professional appointed for these discussions is not always the neurologist.	-	65%
Tuck (2015) 28 USA	n = 255 PwPs; age ranges (n, %): –18–49 (10, 3.9) –50–59 (42, 16.5) –60–69 (109, 42.7) –70–79 (67, 26.3) –80+ (27, 10.6) 39% women	Quantitative cross-sectional survey	-	–PwPs expressed the desire of having their family involved in discussing their disease early, and half of them wanted to discuss advance care documents early (even at the time of the diagnosis).	–It was more common for PwPs to want to discuss these issues when their disease worsened.	90.9%
Walker (2014) 38 UK	n = 168 PwPs Northumberland; 83.1 (6.5) (age at death); 42.9% women; n = 68 PwPs from North Tyneside 81.9 (5.9) (age at death); 51.5% women	Quantitative observational study	–Engaging PwPs and their relatives in decision making regarding preferences at end of life. [informational]	-	-	90%
Walter (2018) 35 Netherlands	n = 89 consultants in neurology; median age: 44 years, ranging from 33 to 64; 38% women; n = 36 residents in neurology; median age: 29 years, ranging from 25 to 40; 69% women	Quantitative observational study	–Education on treatment restrictions and palliative care in general. [informational]	–Decided by the neurologist, who should be sensitive if the patient or his family brought the subject up.	–Cognitive decline is the most important trigger to engage in advanced discussions, followed by physical decline and terminal phase.	95%

- : not applicable; ACP: Advance Care Planning; AD: Advance Directives; ADL: Activity of Daily Living; PD: Parkinson's Disease; PwPs: people with Parkinson's; SPC: Specialist Palliative Care.

Table 4.

Facilitating and hindering factors in healthcare organizations for providing palliative care to PwP.

First author (year) country	Population, number of participants, mean age in years (SD) and percentage women	Study design	Hindering factors	Facilitating factors	Quality assessment ratings (Qualsys)
Akbar, 2024 37 USA	Population: Survey 1: n = 34 medical directors and coordinators at 34 Parkinson's Foundation Centers of Excellence (COE); Survey 2: n = 667 HCPs before an online course on team-based palliative care offered through the Parkinson's Foundation education platform; Survey 3: n = 371 patient-facing HCPs at COE 164 physicians: 43.6 (11.1) years old, : 48% women; 35 nurse/RN; 44.1 (14.0) years old, 97% women 29 Social workers: 42.1 (13.2) years old, 93% women 27 APPS: 42.6 (10.0) years old, 96% women 116 other professionals: 44.0 (13.2) years old, 83% women	Quantitative study, national surveys: survey 1 (to explore available PC services and resources); survey 2 (knowledge of palliative care and attitudes/experiences with PD); survey 3 (perceptions of PC and current PC practices)	–misunderstanding about: common barriers to pain management, patient's qualification for hospice, strategies for discussing difficult emotions. –highest concerns for staffing (62%), time (50%), space (44%), finances (44%), scheduling (35%), billing (26%), telehealth access (15%), and telehealth support (12%).	–understanding of: definition of PC, strategies to improve serious illness conversation, timing appropriateness of a proxy in decision making. –most providers felt comfortable discussing PCs with patients/family as well as discussing hospice, but 30% of physicians and 50% of advanced practice providers (APPs) felt uncomfortable/neutral. –Nurses and Social workers are more comfortable assessing caregiver burnout than physicians and APPs. –Least comfort reported by physicians was for assessing spiritual well-being (27%) and providing spiritual support (23%). –suggesting an understanding that HCPs are expected to provide PC –interests for additional education and coaching were 1) logistics of integrating PC into practice, 2) discussing prognosis/end-of-life with patients/family, and 3) initiating ACP conversations. –respondents reported a positive culture for improvement and change for implementation of PC.	95%
Alvarez Sauco (2023) 68 Spain	Population: n = 58 neurologists, age ranges: age ranges (n, %): –30–40 (15, 25.9) –41–50 (22, 37.9) – > 50 (21, 36.2) No information on gender	Descriptive, observational, cross-sectional study survey	–98% of respondents reported that neurologist have insufficient training in PC, particularly when dealing with AD, management of medical complication and PC sedation. –34% of neurologist reported to be unsure about the referral criteria for PC –25% of neurologists reported that they frequently provided ACP	-	85%
Chen (2023) 91 China	Population: N = 5 PD clinicians, n = 7 PD nurses (33 (26–45) years 68% female), n = 8 PwP 61 (53–73) 50% female, n = 5 caregivers 60 (53–67) 100% female, n = 4 policy makers 46 (40–55), 50% female	Explorative qualitative design	–Misconceptions about PC –Economic burden – financial burden associated with the need for expensive medications used in the treatment –Absence of systematic education and training concerning PC services –Lack of multidisciplinary collaboration –Lack of communication time –Lack of PC resource access –Lack of continuity of treatment –Lack of economic benefits indicators –Cultural and ethical dilemmas –Death is taboo according to traditional Chinese culture –PC is considered unfilial and faced with moral condemnation	–Critical needs (e.g., multiple motor symptoms, psychiatric changes –desire for PC knowledge at patients and caregiver
DiLuca (2020) 75 USA	Population: n = 397,963 PwP who were hospitalized between 2007 and 2014 Palliative care: 10,639; 81.0 (8.2) years, 43% women No palliative care: 387,324, 76,98 (9.7) years; 45% women	Retrospective cohort study; comparison between people who received palliative care to people who did not.	–Gender, income and insurance were strongly associated with palliative care referral. women had a lower incidence of palliative care referrals compared to men (2.51% vs. 2.87%, p < 0.0001). –Patients with Medicare insurance, and those with lower income were less likely to be referred to palliative care. –Racial and ethnic disparities were not found.	–Older age, higher income, higher comorbidity burden and private insurance were associated with a higher palliative care referral.	100%
Fox (2017) 36 Ireland/Cork	Population: n = 19 PwP; 67.9 (8.2) years; 32% women; n = 12 PD caregivers; 68.2 (6.6) years; 92% women	Qualitative study; semi-structured interviews were conducted	–The term palliative care is not familiar –misunderstood as “home help” or “counselling”; only available to people with a cancer diagnosis. –Missing basic information about PD, even to know that it is incurable. –insecurity of what services or supports were available and know how to access these. –feeling ‘left alone’ in the face of their illness due to limited and sporadic contact with health teams. –feeling unsupported when meeting different HCPs at every clinic or hospital visit. –Lack of cohesion between services and uncertainty about the support services available led to frustration among participants and affected the carer's ability to care for the person in need of care.	–PwP wanted sufficient and timely information to adapt housing, contact relevant services	75%
Hasson (2010) 56 UK	Population: n = 15 PD bereaved caregivers; age range from 55 to more than 65 years; 27% women	Exploratory qualitative study;	–Lack of access to home-based palliative services such as hospice care. –Only few caregivers were aware of the responsibilities of palliative care services and hospices –Misconception of PC (only for cancer patients at the end of life)The carers were not aware that death was imminent. –Lack of information on accessibility of services and the role of health and social care professionals involved. –Uncoordinated and patchy access to palliative care and clinical care –Diffusion of responsibilities between HCPs involved. –interaction with specialist were brief and focused on medication, with little or no psychological support or referral to other types of services.	–Referral to bereavement counselling services for former caregivers was described as helpful from one caregiver. –One caregiver recommended that bereavement support should be available before death –One caregiver recommended the establishment of a special multidisciplinary team to be set up to deal with neurological disorders.	90%
Jensen (2022) 42 Germany	n = 87 physicians (45 GPs and 42 Neurologists), 53.5 (9) years, 41,4% women	Quantitative study (monocentric, cross-sectional, observational study)	–17% thought an implementation was impossible but named the economic framework or scarce time in the clinical routine as reasons not to proceed.	–The responsibility concerning the advice on PD-specific advance directives is shared between GPs and neurologists.	100%
Jordan (2020) 62 USA	Population: n = 30 PwPs; 66 (8) years; 37% women; n = 30 PD caregivers; 68 (7) years; 77% women	Qualitative descriptive study; secondary analysis of a large, multi-site randomized clinical trial of interdisciplinary outpatient neuropalliative care compared to standard neurological care for PwPs and care partners		–Team-based approaches with chaplains and social workers can help address and support communications and multiple aspects of palliative care needs. –A roadmap tool can promote individualized anticipatory guidance and multidimensional shared decision-making discussions between patients, care partners, and the healthcare team related to PD progression.	75%
Klietz (2020) 43 Germany	Population: n = 30 experts finished first Delphi round, n = 22 experts predominantly from the workgroup ‘neuro-palliative care’ in Germany performed two Delphi rounds; 40.2 (10.4) years; 36.7% women.	Delphi process	-	–As part of Advance Care Planning, physicians should discuss disease-specific aspects with PwPs for an existing or future living will. –Physicians should explain the added medical value of palliative care when explaining or applying a medication pump.	70%
Kundrick (2023) 31 USA	Population: n = 106 PwPs, 71 (8.4) years old, 46% women	Quantitative study, national survey	–More than half of the respondents either never heard of PC or did not know what it entails. –Half of respondents did not know the difference between PC and hospice.	-	94%
Lennaerts (2019) 32 Netherlands	Population: n = 10 individual interviews with HCPs; 25–64 years; 70% women 3 focus groups with HCPs (n = 29); 25–65 years; 90% women HCPs: neurologist, elderly care physician, psychologist, PD nurse practitioner, community nurse, physiotherapist, speech therapist, occupational therapist, dietician, general practitioner and a psychiatrist	Qualitative Study Interviews with HCPs involved in PD-care	–Lack of clarification of roles and responsibilities in palliative care. –In daily practice, HCPs struggled to identify persons’ needs due to interfering PD-specific symptoms such as cognitive decline and communication problems. –Findings indicate a perceived lack of care continuity, fragmentation of services, time pressure and information discontinuity. –HCPs acknowledged being aware of their lack of knowledge and of their little competence in managing complex PD. –HCPs lack of time for interaction with family caregivers and/or bereavement support.	–Connection between services, Care coordination; need for a central figure to coordinate palliative care. –Availability of specialized palliative care services. –HCPs supported the development of a palliative care system for PD but needed to better understand the essence of palliative care. –Timely addressing the personal preferences for providing palliative care.	90%
Lennaerts-Kats (2022) 90 Netherlands	N = 1029 HCPs involved in PD care; 85% women; 45 (11.1) years.	Quantitative study (pre-posttest intervention design)	–topics “Level of taboo on topics of death and dying” and “Importance of collaboration with network palliative care” did not show any improvement after the blended learning programme.	–blended learning programme: –Increased knowledge of PC, PC for PD, self-perceived knowledge for allied professionals and psychosocial workers, –Increased integration of palliative network and collaboration with palliative care professionals	100%
Lum (2019) 33 USA	Population: n = 30 PwP; 66 (8) years; 37% women n = 30 PD caregivers; 68 (7) years; 77% women;	Qualitative descriptive study;	–PwPs had limited or incomplete understanding of ACP. –ACP is poorly integrated into clinical care. –Lack of physician support for the ACP process, mixed messages about its necessity, and time constraints to discuss ACP in clinic visits. –Lack of PwPs confidence that ACP preferences and documented care wishes are actually respected by physicians or the health system.	–Systematic and routine inclusion of ACP in palliative care visits with clear and open conversations. –Involvement of trained interdisciplinary team members in facilitating ACP conversations.	90%
Prizer (2017) 92 USA	n = 62 neurologists, 45.8 (10.4) years old, 40% female	Electronic national survey	–Physicians may be less likely to refer if (1) they fear a loss of autonomy in patient care, (2) they are unaware of available programmes, and/or (3) they believe they address palliative needs.	–Stronger endorsement of the rewards of PC referrals than the costs –Perceived costs, perceived rewards, physician type, and the number of complementary clinicians in practice influenced PC referral.	100%
Seshadri (2023) 19 USA	n = 1266 PwPs, 71.4 (7.9) years old, 60% women n = 616 caregivers, 70.1 (8.5) years old, 84% women	electronic national survey	–37% PwPs and 33% caregivers reported that when thinking about PC they automatically thought of death and few (17% PwPs; 12% caregivers) felt that accepting PC meant “giving up.”	-	100%
Seshadri (2024) 29 USA	n = 23 PwPs, 69.5 (8.14) years old, 26% women; n = 24 caregivers; 68.88 (9.93) years old, 71% women	Qualitative descriptive research design, semi-structured interviews	–Participants believed PC was about end of life and dying and did not view it as needed early in the disease trajectory –Referral to other specialists is challenging, as they may not understand PD –caregivers lack specific knowledge about PD symptoms	–PC is a way to have a team addressing many PD symptoms and enhancing quality of life, including support for relatives.	65%
Walter (2018) 35 Netherlands	Population: n = 89 consultants in neurology; median age: 44 years, ranging from 33 to 64; 38% women; n = 36 residents in neurology; median age: 29 years, ranging from 25 to 40; 69% women. 16 PwPs were used as cases to elaborate on discussions regarding treatment restrictions.	National online survey;	–lack of education and training in discussions on treatment restrictions in chronic progressive neurological disease in consultants in neurology and residents. No consensus on the treatment policy between physician and PwPs or caregiver/family for readiness in discussing the subject or understanding stopping the treatment. reasons to postpone end-of-life-discussions provided: “The patient could not handle it” (25%, n = 4), “I did not want to deprive hope” (19%, n = 3), “Lack of suffering of the patient” (19%, n = 3) and in one case the neurologist said it would have taken too much time.		95%

- : not available; GP: general practitioner; HCPs: Health care professionals; PD: Parkinson's Disease; PwPs: people with Parkinson's.

Study results

The thematic synthesis identified the following themes:

1. Indicators for timely access to palliative care (RQ1),

2. Advance care planning - right time point for documentation (RQ1),

3. Palliative care needs (RQ2),

4. Indicators for palliative care referral (RQ2),

5. Current models of palliative care delivery (RQ3),

6. Impact of palliative care programmes and multidisciplinary intervention studies for PwPs and related disorders (RQ3),

7. Hindering and facilitating organizational aspects of palliative care for PwPs (RQ4).

Based on the WHO definition of palliative care, the needs of PwPs, caregivers, and healthcare professionals (RQ2) extracted from the records were categorized into four domains: physical, social, psychological, and spiritual needs. ¹ Given the high prevalence of informational and educational needs highlighted in the publications, a fifth dimension, informational needs, was added.

Indicators for timely access to palliative care

Twelve of the 70 articles (17%) contributed to addressing RQ1 (see Table 1). Although evidence-based guidelines are lacking, a significant proportion of PwPs expressed support for early palliative care, particularly at the time of diagnosis and as the disease progresses.^25–28 However, incorporating palliative care from the point of diagnosis does not represent a “one-size-fits-all” solution. Some patients and caregivers prefer to discuss palliative care approaches and ACP only when they perceive a worsening of the disease.^27,29

Regular symptom assessment and increased sensitivity among neurologists to the needs of PwPs and their families are essential to ensure timely referrals and the initiation of ACP discussions.^13,27,30 Despite this variability in preferences, there is growing support for starting ACP discussions earlier in the care process, ³¹ ideally before cognitive impairment develops, which could hinder effective communication about patients’ wishes and preferences.^27,28,32,33

Advance care planning – right time point for communication and documentation

The introduction, discussion, and implications of having ACP documentation were addressed in the included studies. ACP discussions are part of a process that allows individuals to define their goals and preferences for future medical treatment and care, share these preferences with family and HCPs, and document and review them as needed. ² These discussions covered various topics and terms, including Advance Directives, living wills, and medical orders.

Specific indicators for initiating ACP discussions were identified. ²⁷ When at least two of the following indicators were present simultaneously, it was considered appropriate to begin these discussions:

• A request or signal from PwPs to discuss end-of-life issues.

• Expressions of fear or uncertainty about the future.

• Frequent falls resulting in injuries.

• Episodes of dysphagia or pneumonia.

• Cognitive deficits or neuropsychiatric issues.

• Unplanned hospital admissions.^27,33–35

ACP was not always desired by PwPs or their families in the early stages of the disease, often due to the hope for a potential cure.^33,36 Additionally, HCPs frequently postponed end-of-life discussions, fearing that patients might find such conversations overwhelming or that it could diminish their sense of hope. ³⁵ A recent U.S. survey reported that physicians or advanced practice providers (APPs) offered ACP discussions or revisions only rarely, at rates of 4% and 8%, respectively. ³⁷ Moreover, Advance Directives, which outline an individual's preferences for medical treatment, were often lacking.

In a UK study, none of the PwPs who died in a hospital had documented Advance Directives. ³⁸ Although 9% of these patients or their caregivers had end-of-life discussions with a physician, 75% had “do not attempt resuscitation” instructions. Discussions on treatment restrictions typically occurred during the terminal phase, with approximately 70% of neurologists and neurology residents addressing these issues only at that stage.^35,39 Triggers for initiating treatment restrictions or withdrawal in Advance Directives often included physical or clear cognitive decline. ³⁵ The most frequently discussed topics were resuscitation, ventilation, admission to intensive care units, and tube feeding. ³⁵

In a German study involving people with advanced PD meeting inclusion criteria for palliative care interventions, 70% of participants had Advance Directives. Similarly, in a U.S./Canada study involving PwPs or related disorders with moderate to high palliative care needs, 61% had Advance Directives.^39,40 However, in the U.S., only 35% of people with PD listed as a cause of death had completed forms for life-sustaining treatment. ⁴¹

End-of-life discussions are recommended to occur when PwPs and their family members feel prepared to address these topics, considering factors such as age, stage of illness, and personality.^36,42 These discussions often lack clarity for family members, underscoring the need for tailored guidance specific to PD-related scenarios. Recommended additions include advanced therapies, swallowing disorders, bladder and bowel issues, changes in personality, and neuropsychological symptoms. ⁴³

Palliative care needs

In 40 out of 70 publications (57%), the needs of PwPs, caregivers, and HCPs were identified and categorized into five main areas: physical (n = 24), social (n = 31), psychological (n = 38), spiritual (n = 14), and informational needs (n = 48) ⁴⁴ (see Table 1).

Physical needs were frequently mentioned, particularly regarding symptom burden and management, including the need for better pain relief.^37,45–47 Despite this, physical needs were often inadequately addressed. Alongside pain, other disease-related motor and non-motor symptoms were reported as neglected or requiring greater support, such as swallowing difficulties, communication impairments, spasms and stiffness, sleep disturbances, fatigue, and shortness of breath.^29,36,42,48 In general, it was noted that any clinical manifestation negatively impacting quality of life should be prioritized.^13,36

Social needs could be further divided into two subcategories:

1. Socioeconomic Concerns: These reflect the financial burden of the disease and its impact on care provision.

2. Caregiver Support Needs: Caregivers highlighted the effects of social and psychological isolation, emphasizing the need for solutions such as respite care.^48,49

The need for improved care coordination was also expressed, with suggestions such as introducing case managers to address these social needs. ⁵⁰ Case managers could provide advocacy, emotional support, and connections to community resources.^32,51

PwPs often reported that psychological suffering was inadequately addressed, ⁵² especially during critical moments such as diagnosis, which frequently led to feelings of pain, uncertainty, and isolation for both PwPs and caregivers.^36,48,53,54 Anxiety and depression, which significantly affect quality of life throughout the disease course, were often overlooked. ³⁶

Spiritual well-being and bereavement support were rarely considered in clinical care provided by neurologists. This highlights the need for a more holistic approach that evaluates and addresses these needs to improve quality of life.^{13,19,25,37,55–57} Caregivers, in particular, reported feeling unprepared for their roles, struggling with stress, and managing the increasing and extensive needs of PwPs, often without receiving individualized attention or support.^{34,36,37,57,58}

Informational needs were the most frequently reported, accounting for 48 studies. These needs were further divided into three subcategories:

1. Education about the Disease: PwPs and caregivers noted that the lack of information about disease progression impacted their ability to manage symptoms and develop coping strategies, increasing their suffering and uncertainty.^{25,32,47,58–60} They expressed a desire for anticipatory guidance, even when predictions about disease progression were not entirely accurate.^29,50

2. Palliative Care Education: PwPs and caregivers emphasized the need for more information about palliative care, including correcting misconceptions that it is solely associated with oncology. They sought guidance on ACP, end-of-life care, and available PC services.^{26,35,38,39,49,61,62}

3. ACP Documentation: PwPs and caregivers advocated for tailored ACP discussions and support from physicians to ensure their preferences were understood and documented appropriately.^27,33,38,62

Additionally, terms such as guidance, training, and preparation were commonly used in the analyzed papers to describe informational needs. PwPs, caregivers, and HCPs highlighted the importance of timely discussions to include and address their needs effectively.^{25,32,34,58,60}

HCPs also noted a lack of consensus on recommendations for conducting ACP conversations ⁴³ and expressed an urgent need for evidence-based guidelines to manage the disease and address ethical and legal issues, such as feeding tube placement.^32,61 Furthermore, they called for general education on neuro-palliation. ²⁵

Indicators for palliative care referral

Most articles addressing palliative care for PwPs lacked clear clinical indications for referral (see Table 1). Only 31% (22 out of 70) provided information on indicators for referral. Validated scales, such as the Edmonton Symptom Assessment System Scale for Parkinson's Disease (ESAS-PD) and the Palliative Care Needs Assessment Tool (PC-NAT), have proven useful in helping clinicians and PwPs identify prominent symptoms, including those not typically addressed in routine care. A moderate-to-severe score on these scales has been proposed as an indicator for referral.^51,63 However, while these tools show promise for use from early to advanced stages of the disease, they are less reliable in late-stage PwPs due to predominant cognitive decline.^64,65

Another tool designed for HCPs to identify palliative care needs and indicators for ACP is the RADboud Indicator for Palliative Care Needs in Parkinson's Disease (RADPAC-PD). ²⁷ This tool distinguishes between criteria for ACP discussions and the palliative care phase, a distinction critical for initiating early care planning while decision-making capacity and communication abilities are intact.

The burdensome progression of the disease, including its emotional, financial, and social impact on both PwPs and caregivers, has been identified as an indicator for referral.^30,49,56 Advanced stages of PD often require higher levels of care due to increasing disability, physical and psychological deterioration, and prolonged palliative care needs, often extending well beyond the last six months of life.^58,66 Care transitions, such as shifting the focus toward comfort, recurrent hospital admissions, or the need for nursing home placement, also serve as valid indicators for referral.^27,67,68

Referral is further warranted when leaving the home becomes a significant challenge, requiring assistive devices, specialized transportation, or caregiver support to ensure safety.^27,69 Specific disease-related symptoms and complications, such as weight loss, recurrent infections, severe ulcers, swallowing difficulties, malnutrition, psychiatric and cognitive changes, multiple falls, pain, rigidity, respiratory problems, tremor, and constipation, have also been identified as triggers for referral.^6,68,69

PwPs meeting certain criteria, such as Hoehn and Yahr (H&Y) stage 3 or higher, the presence of dementia or psychosis, or significant caregiver strain, have been identified as requiring specialized and comprehensive care. ⁷⁰ Studies investigating predictors of hospice eligibility have noted that symptoms appearing 6–12 months before death, such as significant weight loss (below normal BMI) or reduced use of dopaminergic agents (two or fewer prescriptions), are indicative of advanced needs. ⁷¹

The “surprise question” (SQ: “Would you be surprised if your patient died in the next year?”) has also been used to identify referral needs. Although its accuracy in predicting survival is modest, a negative answer to the SQ has been associated with factors such as older age, dementia, neuropsychiatric symptoms, increased comorbidities, having a care partner, and poor quality of life. ⁷²

Specialist palliative care (SPC) services are beneficial from the time of diagnosis, particularly when medication management becomes complex or when patients and their families need support to cope with the uncertainty of the disease, its impact on identity, and maintaining a positive outlook.^25,36 SPC involvement is especially valuable in managing complications such as aspiration pneumonia and swallowing difficulties. Episodic involvement or enhanced dialogue between PD specialists and SPC professionals has proven effective for discussions concerning ACP. ²⁵

SPC also plays an advisory role in complex cases involving ethical dilemmas or challenging discharges. ²⁵ Triggers for SPC referral identified by PD specialists include perceived deterioration in quality of life, consideration of advanced nutritional strategies (e.g., percutaneous endoscopic gastrostomy [PEG] feeding), unsuccessful symptom management, long disease duration (10–15 years), and advanced stages with cognitive decline. ²⁵ The collaborative approach between PD specialists and SPC professionals enhances the overall quality of care for PwPs.

Current models for palliative care delivery

In examining the current use of palliative care services across eight countries (based on 22 out of 70 publications, or 31%, detailed in Table 2), it became evident that PwPs are infrequently referred to specialized PC services.^{31,37,42,73,74}

Table 2.

Use of palliative care services.

First author (year) Country	Population; number of participants, mean age; percentage women	Study design and/or care models	Use of care	Quality assessment rating (QualSys)
Akbar (2024) 37 USA	Population: Survey 1: n = 34 medical directors and coordinators at 34 Parkinson's Foundation Centers of Excellence (COE); Survey 2: n = 667 HCPs before an online course on team-based palliative care offered through the Parkinson's Foundation education platform; Survey 3: n = 371 patient-facing HCPs at COE 164 physicians: 43.6 (11.1) years old, 48% women; 35 nurse/RN; 44.1 (14.0) years old, 97% women 29 Social workers: 42.1 (13.2) years old, 93% women 27 APPS: 42.6 (10.0) years old, 96% women 116 other professionals: 44.0 (13.2) years old, 83% women	Quantitative study, national surveys: survey 1 (to explore available PC services and resources); survey 2 (knowledge of palliative care and attitudes/experiences with PD); survey 3 (perceptions of PC and current PC practices)	–services available (COE): support groups (82,4%); mental health counselling (70,6%), outpatient palliative care services (41.2%), chaplain/spiritual counsellor (17.6%); peer navigator (17,6%), none (8,8%). –palliative care resources attached to the COE: outpatient palliative care services (58,8%); mental health counselling (61,8%); chaplain/spiritual counsellor (50%); support groups (35%); none (5,9%) –use of services (community connections): support groups (85,3%); hospice (79,4%); mental health counselling (67,6%), chaplain/spiritual counsellor (23,5%), none (5,9%) –Most physicians (58%) and APPs (72%) monitored and managed (69% of physicians) non motor symptoms, only 6% of physicians and 4% of APPs managed pain routinely. –mood symptoms are managed routinely by 44% of physicians and 40% APPs but the referral for spiritual/grief/guilt support occurred less commonly. –half of the responders never used a scale to assess caregiver burnout, but when burnout was suspected, caregivers were reported to be referred routinely for outside services by physicians 15%, APPs 0%, nurses (RNs) 16%, and social workers (SWs) 46%. –Anticipatory guidance is provided by 21% of physicians and 16% APPs, a review/discussion of ACP is offered less frequently (4 and 8% respectively). SWs (30%) standout as routinely discussing ACP. –55% of physicians reported referring <50% of these patients to a specialist, and 9% referred none of their high needs PC patients to a specialist. Of the end-stage patients, most physicians (70%) reported referring <50% of patients to hospice, and 7% of physicians referred none of these patients.	95%
Alvarez Sauco (2023) 68 Spain	Population: n = 58 neurologists, age ranges: age ranges (n, %): –30−40 (15, 25.9) –41–50 (22, 37.9) –> 50 (21, 36.2) No information on gender	Descriptive, observational, cross-sectional study survey	–less than 10% of their patients with movement disorders eligible for PC received it.	85%
Bhansali (2023) 80 USA	Population: n = 35 PwPs at End of Life (EOL), 80.2 (9.9) years old, 29% women. Hospice care: n = 27, 80 (10.5) years old; Expired in hospital: n = 8, 80.6 (8.2) years old n = 692 PwPs non-EOL group, 75.5 (12.1) years old, 42.5% women	Retrospective cohort study, Comparison of PwPs in EOL group (died in hospital or were discharged with hospice) with PwPs non-EOL group (admitted to hospital).	– EOL Group showed: – low utilization of PC services and delayed discussions of goals of care – 46% received PC consultation – 49% underwent invasive procedures – 23% had a “Do Not Resuscitate Comfort Care” (DNR CC) code status on admission, – code status was changed in 100% to DNR CC during hospital stay within a median of 4.5(IQR 1.5–9) days (expired in hospital) and 5 (IQR 2–10) days (hospice). – Death occurred at a median of 0 days from transition to comfort care for PwPs that expired in the hospital. – final disposition: home with hospice (37.1%); Hospice facility or inpatient hospice (40%) – PwPs that expired in the hospital had a higher percentage of invasive procedures and ICU admissions compared to the hospice group (75% vs. 41%, respectively for both variables)	90%
Di Luca (2020) 75 USA	Population: n = 397,963 PwPs who were hospitalized between 2007 and 2014 Palliative care: n = 10,639 PwPs; 81.0 (8.2) years; 43% women No palliative care: 387,324 PwPs; 77.0 (9.7) years; 45% women	Retrospective cohort study, comparison between people who received palliative care to people who did not.	–In-patient palliative care consultations were sparse, but increased from 0.85% in 2007 to 4.49% in 2014. –Race or ethnicity did not seem to influence palliative care referral. –Women were less likely to be referred to palliative care services, while higher income, higher comorbidity burden and private insurance (when compared to Medicare) were associated with a higher palliative care referral.	100%
Hasson (2010) 56 UK	Population: n = 15 bereaved PD caregivers; age range from 55 to more than 65 years; 27% women	Qualitative exploratory descriptive study; semi-structured interviews	–Lack of access to and awareness of domiciliary palliative care; care coordination was often not in place and as such some patients were not referred to potential beneficial care of allied health professionals. –Access to specialist care was hindered by lengthy waiting times. Many carers relied on their general practitioner, although some felt a lack of detailed PD knowledge negatively influenced the patient's health. –Only one carer received bereavement counselling, although carers thought such counselling should be available to all who need it.	90%
Jensen (2022) 42 Germany	n = 87 physicians (45 GPs and 42 Neurologists); 53.5 (9) years; 41.4% women	Quantitative study (monocentric, cross-sectional, observational study)	–none of their PwPs or only 1–5% received palliative care (57%) (% of physicians reported) –less than 25% of PwPs had written advance directives (27.6%) –more than 75% of PwPs were provided with a written advance directive (6.9%) –did not know whether their PwPs had written an AD or not (19%) –The neurologists spent overall less time than GPs in consultations on advance directives (p = 0.018) –One-third of the neurologists and 15,6% of the GPs included some of the previously published PD-specific recommendations in advance directives	100%
Klietz (2018) 39 Germany	Population: n = 76 PwPs with (advanced) PD meeting inclusion criteria for palliative care interventions; 76 (6.1) years; 53.9% women	Prospective quantitative and qualitative analyses	–PwPs approximately 50% scheduled regular outpatient neurologist visits –70% had an advance directive and a health care proxy –less than 3% received actual palliative care. –72% wanted information about PC and 58% discussed it with the family.	70%
Kluger (2020) 40 USA and Canada	Population: PwPs with moderate to high palliative care needs Intervention: n = 106 PwPs; 70 years; 39% women; Control: n = 104 PwPs; 71 years; 33% women	Randomized controlled trial, baseline measurement was used	–61% of PwPs had an advance directive	95,8%
Kristjanson (2006) 79 Australia	Population: n = 174 PwPs; 70(8) years; 35% women. n = 141 carers; 66(10) years; 74% women	National survey	–8% of PwPs and 7% of carers received palliative care services. 22% of PwPs and 18% of carers received home care.	95%
Kundrick (2023) 31 USA	Population: n = 106 PwPs, 71 (8.4) years old, 46% women	Quantitative study, national survey	–93% of the respondents reported to have never been offered to or used either PC services.	94%
Lökk (2011) 96 Sweden	Population: n = 70 PwPs or related disorders (i.e., Parkinsonisms, Cortico-Basal Syndrome) within the permanent care unit PwPs n = 62; 77 (60–90) years; 49% women	Report of the use of a PD permanent care unit. PwPs are eligible for this care unit if they have intensive medical and care needs, and are no longer able to stay at home or at an ordinary institution. A written and continuously reviewed care plan is made for each patient at admission, with the overriding aim to preserve quality of life and optimize functionality	–70 patients within 5 years –The mean duration of a stay was 27 months (1–58). –5 patients moved out from the PD permanent care unit due to social reasons. –13 acute transfers to hospitals due exacerbation or new onset of comorbidity, but none due to Parkinsonism per se. –The mean annual fatality rate was 7 (5–8), with pneumonia as the most common cause of death. –During the last 3 years, there was a waiting list admission of 2.5 months.	50%
McKenzie (2022) 74 USA	Population: n = 1439 adult death with neurodegenerative movement disorders PwPs n = 1226 (85.2%) 80 years and older 63%, 65 years and younger 6%, 40% women	Retrospective cohort study, health care use and sociodemographic data for all deaths.	–in the last year of life ≥1 outpatient neurology visit (37,2%) –≥ 1 palliative care consultation (17.4%; inpatient consultation in 10.6% compared to 8.8% outpatient) Those with early palliative care (≥90 days before death) died outside hospital more frequently than those with late or no palliative care involvement –Dying in hospital was more likely to those that reside in a rural location, have dementia, had more days spent in hospital, more hospital admissions, more ED visits and more ICU admissions in the last year of life –Those who died in hospital were more likely to have outpatient neurologist and other specialist consultations in the last year of life	95%
McQueen (2022) 89 USA	UCH outpatient neurology clinic for PC and movement disorders.	Application of time-driven activity-based costing with reimbursable visits calculated using Medicare reimbursement rates in Colorado and current procedural technology codes to 2 outpatient clinics at the University of Colorado Hospital: neurology PC and movement disorders.	–The primary driver of cost be- tween the neurology PC clinic and the comparator clinic was the time spent with each provider and the number of providers. –The additional time and number of providers resulted in a time and space cost per visit of $154 and $82 for new and established visits, respectively, at the neurology PC clinic. In contrast, the movement disorders clinic visit time cost was $98 and $41 for new and established visits, respectively –Between movement disorders clinic and palliative care one there is an incremental cost difference of approximately $35,000. –Extrapolating revenue the neurology pc clinic has an incremental added revenue of approximately $40,000 compared to the movement disorders clinic alone. –for every $1 invested in the neurology PC clinic, $1.68 cents will be recouped by the hospital system for new patient visits, and $0.13 will be recouped for established patient visits.	100%
Prizer (2017) 92 USA	n = 62 neurologists, 45.8 (10.4) years old, 40% female	Electronic national survey	–54.2% of the participants referred PwPs to non-terminal palliative care, with the average annually number being 4.34	100%
Rosenwax (2016) 73 Australia	Population: n = 181 PwPs No available information about age and gender.	Retrospective cohort study, comparing the proportion of descendants receiving specialist palliative care in the last year of life in 2009–2010 to 2000–2002. Specialist palliative care could be community-based (referral needed from a medical professional and includes at-home physical care and practical support, symptom management, counselling and respite care) or hospital-based (care in a palliative care unit, in designated palliative care programme or under a palliative care specialist, or when the care intent is palliation).	–21 PwPs (12%) had access to specialist palliative care in 2009–2010. Palliative care was provided in the hospital (n = 15), at home (n < 5) or both at home and in the hospital (n < 5). This was an increase of 8% compared to 2000–2002.	90.9%
Safarpour (2015) 77 USA	Population: n = 469,055 PwPs Medicare beneficiaries, from 2002; aged >65 years Medicare is a government-mandated insurance and prescription programme used by 98% of adults aged 65 years and older Long-term care facility: n = 113,668 PwPs; 82.3(6.9) years; 58% women Community: n = 355,387 PwPs; 78.7(7.0) years; 49% women	Retrospective cohort study, comparison between people residing in long-term care facilities and the community.	–24% of PwPs resided in a long-term care facility. These were older, more often female and had a greater comorbidity burden than community-dwelling PwPs. African Americans were relatively overrepresented in long-term care facilities, while Hispanic individuals were underrepresented (compared to the community) –33% of long-term care facility residents received outpatient neurologist care. These were healthier, more often white and used more often hospice services than PwPs without outpatient neurologist care. –Almost 85% of PwPs in a nursing home died within 3–4 years. 54% of nursing home residents used hospice care.	90%
Seshadri (2023) 19 USA	n = 1266 PwPs, 71.4 (7.9) years old, 60% women n = 616 caregivers, 70.1 (8.5) years old, 84% women	electronic national survey	–4% of PwPs and 8% of caregivers reported that the PD provider discussed palliative care with them. Half of them were referred to SPC services. –Hospice referral was discussed with the 2% of participants, 31% of PwPs and 67% of caregivers were then referred. –PwP receiving care at Parkinson's Foundation's Centres of Excellence (COE) had higher education and income than those receiving care at non-COE. –Differences in care provision between COE and non-COE were in the assessment of non-motor symptoms, caregivers’ needs and support and in the effectiveness of communication with providers.	100%
Sleeman (2013) 76 UK	Population: n = 125,242 deceased PwPs Average age at death was 81.4 (7.1) years. Underlying causes of death were sole PD (6%); PD and one additional contributory cause (38%) or PD and two or more additional contributory causes (56%)	Population-based study	–Place of death: at home (10%), care home (46%), hospital 43% or hospice (0.6%).	100%
Teggi (2020) 78 UK	Population: PwPs who received help with at least one activity of daily living No available information about age and gender.	Retrospective study comparing the likelihood of receiving care through several long term care arrangements (LTCAs): informal care at home, formal care at home, mixed formal and informal care at home, care home, hospice.	Compared to the other long term care arrangements, PwPs were more likely to: –Receive informal home care (19 percentage points) –Receive mixed formal and informal home care (56 percentage points) –Live in a care home (31 percentage points) In contrast, compared to other long term care arrangements, PwPs were less likely to: –Receive formal home care (59 percentage points) –Die in a hospice (47 percentage points).	85%
Tuck (2015) 41 USA	Population: n = 1073 deceased PwPs who had PD as the primary or secondary cause of death. These were compared to 56,961 people with all other natural death causes. PD: 82.7 (7.6) years; 38% women; Non-PD: 76.1 (15.9) years; 52% women	Retrospective analyses of Oregon death certificates and match these to the Oregon Physician Orders for Life Sustaining Treatment (POLST) Registry	–Mean time between POLST completion and death was 7 weeks for PD. –Descendents with PD were more likely to have died in a nursing home (52 vs 29%) and less likely to die at home (32 vs 39%) or in a hospital (13 vs 24%) than non-PD. –PD and non-PD did not have different orders for Do Not Resuscitate, Comfort Measures Only or Artificial Nutrition. 35% had a POLST-form. –Within descendants with PD, those with completed POLST forms were less likely to die in a hospital (8 vs 15%) and more likely to die at home (38 vs 28%). Descendents with Comfort Measures Only were even less likely to die in an inpatient setting (5%) and more likely to die at home (39%).	100%
Walker (2014) 38 UK	Population: n = 168 PwPs Northumberland; 83.1 (6.5) (age at death); 42.9% women; n = 68 PwPs from North Tyneside 81.9 (5.9) (age at death); 51.5% women	Retrospective assessment of medical records Liverpool care pathway: this care model has been shown to provide good end-of-life. The Neuerberg rapport recommended that this care pathway should be replaced by individualized care plans.	–Place of death: hospital (47%), at home (24%), care home (25%) or not recorded (5%). 1 person died in a hospice. –Of the patients who died in a hospital, 14% were referred to specialist palliative care and 9% (patient or caregiver) had recorded end-of-life discussion with a physician. –No patient had an advance care directive. The Liverpool care pathway and do not attempt resuscitation instructions were used in 42% and 75% of cases. Almost all patients on the Liverpool care pathway did not continue with dopaminergic medication.	90%
Walter (2018) 35 Netherlands	Population: n = 89 consultants in neurology; median age: 44 years, ranging from 33 to 64; 38% women; n = 36 residents in neurology; median age: 29 years, ranging from 25 to 40; 69% women. 16 PwPs were used as cases to elaborate on discussions regarding treatment restrictions.	Survey Analyses of 16 PwPs cases with whom discussion on treatment restrictions took place. Care model: regular neurological care	–Survey: discussions on treatment restrictions started commonly not earlier than the terminal phase, in which about 70% of neurologists and residents discussed treatment restrictions. –Physical or clear cognitive decline were triggers to start treatment restrictions. –Case analysis: withdrawal/withhold of resuscitation (75%), ventilation (75%), admission to intensive care unit (75%) and tube feeding (63%) were discussed most frequently.	95%

GPs: General Practitioners; PD: Parkinson's Disease; PwPs: people with Parkinson's.

In Australia, only 12% of PwPs accessed SPC services during their final year of life, typically in hospitals and occasionally at home. In Spain, neurologists reported that less than 10% of eligible patients with movement disorders received palliative care. ⁶⁸ In the United States, only 4% of PwPs and 8% of caregivers reported that their PD providers discussed palliative care with them. Additionally, only 4.5% of hospitalized PwPs received inpatient PC consultations.^73,75

Two studies noted an upward trend in PC referrals: in Australia, there was an 8% increase between 2000 and 2002, and in the U.S., a 3.6% increase was observed between 2007 and 2014.^70,71 However, gender disparities were evident in the U.S., with women less likely to be referred to PC services. ⁷⁵

In the UK, 14% of PwPs who died in hospitals were referred to SPC teams, and 42% were placed on the Liverpool Care Pathway (LCP). ³⁸ Importantly, most PwPs on the LCP had their dopaminergic medications withdrawn, a practice linked to worsening symptoms and accelerated clinical decline in PD. ³⁸

Hospice care, a well-established PC approach, provides comprehensive, multidisciplinary support for patients nearing end-of-life. In the UK, fewer than 1% of PwPs died in hospice facilities, while in the U.S., 54% of nursing home residents received hospice care.^38,76–78 In Australia, a national survey found that only 5% of PwPs received PC services. ⁷⁹ Similarly, a German national survey reported a 3% provision rate of PC for patients with advanced PD. ³⁹

In a retrospective U.S. study of PwPs at the end of life, 46% received PC consultations. ⁸⁰ Of these, 40% were discharged to hospice facilities or inpatient hospice, 37% received home hospice care, and 23% died in the hospital. Notably, PwPs who died in the hospital had higher rates of invasive procedures and ICU admissions compared to those who received hospice care (75% vs. 41%). ⁸⁰

Impact of palliative care programmes and multidisciplinary interventions for PwPs and related disorders

Eleven of the 70 studies (16%) evaluated the effects of various PC programmes for PwPs and related disorders (detailed in Table 3).^{40,69,81–84}

Table 3.

Intervention studies evaluating (new) models for providing palliative care.

First author(year) Country	Population; number of participants, mean age; percentage women	Study design and/or care models	Evaluation and effects of the palliative care model	Quality assessment rating (QualSys)
Bock (2022) 84 USA and Canada	(See Kluger, 2020) 40	(See Kluger,2020) 40	–The intervention group reported greater improvement in perceptions of the “self as a whole” at 6 months. –Care partners reported greater reduction in stress, anger and loss of control at 12 months. –Improvement in numerous non-motor symptoms and grief correlated with improved patient QoL, reduced patient anxiety and increased care partner spirituality. –Alleviation of care partner anxiety and depression correlated with reduced care partner burden.	100%
Bock (2024) 50 USA	(See Kluger, 2024) 88	(See Kluger, 2024) 88	–effectiveness of the multidisciplinary approach in addressing a greater range of needs (spiritual, sense of self) –Facilitation of direct conversations about the future assistance with advance care planning –Greater engagement with the health care team under palliative care model, increased care coordination –Increased referrals to other providers and connection to community-based resources	95%
Eggers (2018) 81 Germany	Population: PwPs Intervention n = 132, 69.8 (8.4) years, 36% women. Control n = 125, 69.9 (7.8) years, 42% women.	Randomized controlled trial Intervention –Intervention team: PD nurse –The PD nurse synchronized the therapeutic pharmacological intervention with the programme of speech therapists or physiotherapists. –3-monthly visits for 6 months. When necessary additional appointments on short notice could be made. Regular neurological treatment + the development of an individual treatment plan, 3-monthly home visits of a PD nurse (or when necessary, on short notice) and a telephone hotline. Therapeutic modification could be made due to the assessment of the PD nurse, feedback of patient or feedback of therapists. Control Regular neurological treatment.	The intervention had positive effects on: quality of life (PDQ-39) motor and non-motor symptoms (UPDRS-III and PD-NMS, respectively). No intervention effects were found for cognition and depression.	75%
Fleisher (2018) 82 USA	Population: PwPs and related disorders with at least 1 high-risk condition for hospitalization n = 67 PwPs and n = 18 PD-related disorders. Age median (interquartile range): 79.6 years, (72.5–84.8) 51.8% women.	Retrospective chart review using the institutional electronic medical record for all intervention visits. Intervention –Interdisciplinary home visit programme to provide continuity of expert neurological care to homebound individuals with advanced PD and related disorders. –Intervention team: movement disorders neurologist, social worker (who also served as programme coordinator), and a nurse. –The entire intervention team convened weekly to review recent patients, identify outstanding concerns and strategize about process improvement. After each home visit, comprehensive interdisciplinary note was shared with the patient's healthcare providers. Referrals to other healthcare professionals were also coordinated. –4-monthly home visits	–The home visit programme showed high retention and satisfaction. –Medication changes were recommended at 41.9% of all visits, while nonpharmacological treatment changes were recommended in 45.2%. Therapy or service referrals were made at 92.7% of visits.	95%
Fleisher (2020) 69 USA	Population: PwPs who were homebound and had missed >1 recent appointment or had been hospitalized or temporarily institutionalized in the preceding year. n = 27, 80.9 (7.8) years, 56% women.	Interventional monocentric single arm pilot study Intervention Intervention team: neurologist, social worker and nurse. The intervention team became the PwPs's default care provider during the study period. –All health care providers received a comprehensive interdisciplinary note send by the study neurologist –3-monthly home visits for 12 months Home visits: history, examination, medication reconciliation, psychosocial evaluation, pharmacologic and nonpharmacologic management, and service referrals. No control group	–Quality of life did not decline over 1 year, despite disease progression. –Healthcare utilization did not significantly change during the intervention. –None of the participants were institutionalized during the study.	85%
Fleisher (2022) 86 USA	Population: PwPs aged ≥ 40, ≥ 1 risk factor caregiver strain and/or institutionalization, H&Y ≥ 3; N = 65 dyads of PwP 78.9 (7.6) years, 32.3% female Control group: N = 319, 70.1 (7.8) years, 37.9% female	Single-centre nonrandomized controlled study Intervention Intervention team: research nurse, social worker and a research coordinator. A movement disorder specialist was present remotely via telemedicine. –1 year of structured, quarterly, telehealth-enhanced home visits –study visits occurred at home or in the long-term facility if institutionalized Home visits: history, examination, medication reconciliation, home safety assessment, psychosocial evaluation. A comprehensive note was then sent to the treating healthcare professionals. Control Group Usual care, longitudinal data of PwPs from Parkinson's Outcome Project (POP) and those receiving usual care at Center of Excellence (COE). Annual clinical visits, or more frequently depending on patient need.	–QoL remained unchanged in the intervention group, while in the control group decreased over time. –PwPs in the intervention group declined in mobility and activities of daily living without changes in emotional well-being, social support or cognitive impairment. PwPs in the control group declined in all dimensions of QoL, with only bodily discomfort remaining stable. –PwPs in the intervention group reported an improvement in self-reported stigma and communication.	100%
Fleisher (2023) 87 USA	Population: PwPs who were homebound, ≥ 1 risk factor for loss to follow up, hospitalization or institutionalization, H&Y ≥ 3; N = 65 dyads of PwP 78.9 (7.6) years, 32.3% female and caregiver 64.1 (11.5) years, 78,5% female Control group: historical controls from the Parkinsońs Outcomes Project – usual care at Center of Excellence N = 319 70.1 (7.8) years, 37.9% female, data on caregiver missing.	Nonrandomized controlled trial Intervention Intervention team: nurse, social worker, accompanied by telehealth connection with a movement disorder specialist. Multi-professional team – four structured, interdisciplinary, telehealth enhanced home visits over one year. PLUS Peer mentoring programme –Educational material for PwP and caregivers (Handbook focused on common symptoms and scenarios prompting urgent or emergent care and approaches to recognition and management) –Social worker – offered referrals to community services through state and local jurisdictions –Nurse called caregiver 2–4 weeks after each home visit –Peer mentoring programme –Peer mentor training –Mentor matching –Peer mentoring – speak with their mentees for 30 min weekly by phone, videoconference or in person. –Quarterly calls for mentors	–No change in caregiver strain between baseline and one year while control worsened slightly – not significant –Peer mentoring is feasibly, mentees and mentors rated 100% of visits as useful –Post hoc pairwise comparisons, anxiety improved slightly between home visit 1 and 3, no changes in depression, no changes in depression of peer mentors, symptom management self-efficacy, community support services use	100%
Fu, 2024 85 China	Population: n = 103 PwP nurse-led palliative care;61.54 (5.69) years old, 30% women n = 134 PwP neurologist-led standard care; 61.11 (5.79) years old, 40% women n = 168 PwPs primary care practitioner-led usual care; 61.8 (5.24) years old, 39% women	Retrospective study, nurse-led palliative care with neurologist-led standard care and primary care practitioner-led usual care during six months Intervention: Nurse-led palliative care Nurses available at the institute for PwPs visits with no time limit. Nurses discussed the goal of care, difficult emotions and anticipatory guidance, educated PwPs and caregivers. Physical rehabilitation was part of the intervention too. Neurologist-led standard care Neurologists could be contacted at the institutes, visits had a 15-mi time limit. Neurologists discussed and educated PwPs and caregivers about goal of treatments, symptom management. Primary care practitioner-led usual care Primary practitioners were available at the institute for PwPs visits with no time limit. They discussed the goal of care, caregiver support, difficult emotions and anticipatory guidance. Caregivers and PwPs are advised to perform Tai Chi exercises at home.	–QoL improved across all three groups, but was higher in the nurse-led intervention group. –caregiver burden: decreased in all groups compared to pre intervention assessment. The lowest scores were present in the nurse-led intervention group. –patient satisfaction: improved across all three groups, but was higher in the nurse-led intervention group.	77%
Kluger (2020) 40 USA and Canada	Population: PwPs; Intervention n = 106 PwPs, 70 years, 39% women n = 87 caregivers, 66 years, 71% women Control n = 104 PwPs, 71 years, 33% women n = 88 caregivers, 66 years, 75% women	Randomized controlled trial Intervention Standard care + outpatient integrated PC administered by a neurologist, social worker, chaplain, and nurse using PC checklists, with guidance and selective involvement from a palliative medicine specialist. –Palliative care team: neurologist, nurse, social worker, chaplain and palliative care specialist. –Palliative care team worked together. –In addition, help with care coordination with other healthcare professionals was part of the intervention. –3-monthly outpatient visits for 12 months –18% of participants in the intervention group used telemedicine for at least 1 visit. Control Standard outpatient neurology care.	–The intervention group showed a higher patient quality of life at 6 months than the standard care group. At 12 months this group difference was no longer present. –At 6 months, caregiver burden was not different between groups, but at 12 months the intervention group showed a lower caregiver burden than the intervention group.	95,8%
Kluger (2024) 88 USA	Population: Intervention group: n = 179 PwP, 73.6 (9.1) years old, 38% women; n = 143 caregivers, 65.8 (12.1) years old, 78% women Control group: n = 180 PwP, 74.4 (7.6) years old, 32% women; n = 157 caregivers, 69.2 (10.3) years old, 75% women	Non Blinded, stepped-wedge, pragmatic comparative effectiveness trial. Intervention: PC referral: had 1 or more PC needs on the Brief Needs Assessment Tool Provide PC education and coaching to community clinicians with a dedicated programme (EPEC) and follow up coaching sessions (on need basis, and every 6 months assessment of skills). Direct-to-home telemedicine consultations from the PC team (PC-trained physician, nurse, pharmacist, social worker, chaplain, and peer navigator) One meeting with the core PC team (physician, social worker, and chaplain) at least once at the start of the study, subsequent visits on an as-needed basis by referrals from community physicians or study coordinators. Control: Standard neurological care and from any associated HCPs. Clinicians could refer to other services at their discretion, including PC, once patients were enrolled.	–Compared with standard care at 6 months, participants receiving PC had a better QoL. Treatment effect at 6 months was influenced negatively only by disease duration. –No effects were observed in caregiver burden after the intervention, except for Hispanic and rural caregivers. –Treatment effect in favour of PC for depressed mood at 6 months –The treatment effect for caregiver strain at 6 and 12 months adjusted for covariates favoured standard care –At 6 months, persons receiving PC were more likely to have completed AD, health proxy but not state-specific living wills. –Knowledge in HCPs increased after training, but improvement wore off by 6 months post training. –PC practices were more effective on participants after 13 months or longer post-training than in the first year after training.	100%
Spilsbury (2017) 83 Australia	Population: 181 deceased PwPs. No further demographics were provided.	Retrospective population-based cohort study: –Health care costs, over the year prior to death, of patients which received community-based specialist palliative care were compared to patients which did not receive this care. –Community-based specialist palliative care: palliative care clinicians and nurses, allied health professionals and volunteers provide home nursing care, counselling, respite options, practical support and links to other services with the aim of enabling people with a life limiting illness to remain at home. A palliative nurse consultancy service was available for residential care facilities.	–Community-based specialist palliative care reduced cohort averaged hospital costs from around 45 days on prior to death in people with PD. –There was no association between community-based specialist palliative care and average inpatient hospital costs.	95%

PD: Parkinson's Disease; PwPs: people with Parkinson's.

In a Chinese study, the outcomes of a six-month nurse-led PC intervention were compared to standard care provided by neurologists or physicians. While improvements in quality of life (QoL), caregiver burden, and patient satisfaction were observed in all groups, the nurse-led intervention demonstrated the most significant benefits. ⁸⁵ Similarly, in Australia, community-based PC for deceased PwPs reduced hospital costs compared to those who did not receive such care. ⁸³

In Germany, a combination of standard neurological care, supplemented with three-monthly home visits by a PD nurse and the development of individualized treatment plans, significantly improved QoL compared to standard neurological care alone. Additionally, both motor and non-motor symptoms decreased, as measured by disease-specific scales (UPDRS-III and PD-NMS, respectively). ⁸¹

In the U.S. and Canada, a hospital-based PC intervention involving a neurologist, nurse, social worker, chaplain, and palliative care specialist also enhanced QoL for PwPs. Patients in the intervention group reported higher QoL at six months compared to those receiving standard care, along with a decrease in caregiver burden at the 12-month follow-up.^40,84 These findings align with results from studies in Australia and the U.S., where QoL indexes remained stable over 12 months despite disease progression, and there was no increase in the utilization of health services, such as long-term care facilities and hospitalizations.^69,82,83,86 These programmes also reported high retention rates and satisfaction levels, with adjustments to therapy and referrals to non-pharmacological treatments occurring in over 40% of cases. ⁸²

Caregivers also benefited from these interventions. For instance, interdisciplinary programmes and peer mentoring effectively mitigated and stabilized caregiver burden in a cohort of homebound PwPs. ⁸⁷

A recent trial ⁸⁸ tested the impact of community-based PC, which included palliative care training for community neurologists and coaching from senior PC specialists to address challenging cases. PwPs were referred to a multidisciplinary telemedicine PC team comprising a nurse, pharmacist, social worker, and chaplain. The intervention addressed overlooked needs such as spiritual support and facilitated discussions on advance ACP and future care preferences. ⁵⁰

The programme demonstrated several benefits compared to standard care, including improved QoL, reduced depressive symptoms, and higher completion rates of Advance Directives at six months. Participants also experienced enhanced care coordination, increased referrals, and stronger connections to community resources. ⁵⁰ Modest improvements in HCPs’ knowledge about PC were also observed. ⁸⁸ These findings underscore the potential of palliative care programmes to improve both patient and caregiver outcomes through tailored, interdisciplinary approaches and innovative delivery models.

A U.S. study analyzed the costs and return on investment of team-based palliative care using Medicare reimbursement rates. In an academic medical setting, the neurology PC clinic demonstrated financial sustainability. For every dollar invested in expanding PC services, the hospital system recovered $1.68 for new patient visits and $0.13 for established patient visits. ⁸⁹ This evidence underscores the variability in PC utilization across countries, the challenges in equitable access, and the potential for economic viability when PC services are effectively integrated into healthcare systems.

Barriers and facilitators for access to and provision of palliative care for pwPs

Barriers and facilitators to palliative care access, identified in 17 of 70 publications (24%) (detailed in Table 4), can be categorized as follows: education, challenges in determining the right time for palliative care, end-of-life care preferences and ACP, home-based palliative care services, and the influence of race, ethnicity, gender, and income.

Educational needs span PwPs, caregivers, and HCPs. PwPs often lack basic information about their condition, and even HCPs harbour misconceptions about palliative care.^{19,29,35,36,56} Training in palliative care for HCPs is identified as a key facilitating factor.^37,90 Two studies emphasized that HCPs must deepen their understanding of the core principles of palliative care to support the development of effective PC systems for PD.^32,91,92

To enable PwPs and caregivers to access palliative care, timely information about available services and emotional preparation, especially for end-of-life and bereavement, is essential.^25,56 However, identifying clear indicators for appropriate and timely PC referrals remains challenging, affecting both caregivers and HCPs.^32,56 HCPs often struggle in daily practice to recognize the needs of PwPs, interpret them accurately, and refer them promptly to appropriate services.^34,37 For instance, family members may not realize that death is imminent, leaving them unprepared to handle sudden crises. ⁵⁶

Another significant barrier is the discomfort surrounding discussions about ACP and end-of-life care. Many PwPs and caregivers find these conversations distressing, leading to delays. ³⁵ HCPs themselves often feel unprepared for such discussions, citing a lack of personal strategies to navigate the emotional complexities involved. ³⁷ When physician interactions are brief and lack psychological support or referrals to other services, care planning and coordination become inadequate, resulting in reactive, ad hoc access to services. ⁵⁶

PwPs and caregivers also fear that documented ACP preferences may not be respected by physicians or the healthcare system, further hindering their willingness to engage in ACP discussions. ³³ Additionally, the fragmented healthcare system provides inconsistent support to PwPs and caregivers, with limited and sporadic contact leaving many feeling “abandoned” in managing the disease. ²⁵

A lack of continuity in care further exacerbates these challenges. PwPs and caregivers often encounter different health professionals with each visit to clinics or hospitals, leading to frustration and uncertainty about available support services.^25,32,56 This fragmentation results in uncoordinated and inconsistent access to both clinical and palliative care. For PwPs without a caregiver, access to palliative care is particularly difficult, as caregivers often play a central role in organizing and facilitating care. ²⁵

Many PwPs prefer to remain at home despite their deteriorating health. However, inadequate home-based palliative care services often make this option unattainable. ⁵⁶ Beyond the availability of specialized PC services, a strong connection between services and multidisciplinary collaboration is critical to ensure access. ³² Establishing dedicated multidisciplinary teams for managing neurological conditions, supported by a central coordinator, is essential.^56,62

Diversity factors also influence access to palliative care. While race or ethnicity did not affect PC referrals for PwPs in one U.S. study, ⁷⁵ cultural factors in certain regions, such as traditional Chinese beliefs, create barriers. In these cultures, topics related to death and dying are taboo, preventing discussions about ACP and treatment preferences. ⁹¹

Additionally, socioeconomic factors strongly influence PC referrals. Female PwPs, those with lower incomes, and those without private insurance are significantly less likely to be referred to palliative care. ⁷⁵ Addressing these disparities is crucial for ensuring equitable access to palliative care services.

Overcoming these barriers requires targeted education, better coordination of services, culturally sensitive care practices, and efforts to reduce socioeconomic disparities. By addressing these challenges, the provision of palliative care for PwPs can be significantly improved, enhancing both patient and caregiver outcomes.

Discussion

This systematic review synthesizes how PC is currently provided for PwPs and their caregivers, focusing on clinical indicators for referral and opportunities for early integration into traditional care management. It also offers a comprehensive overview of facilitators and barriers to PC access.

Delivering care to PwPs is inherently complex due to the diverse phenotypes, progression rates, and individual needs/preferences associated with PD.^93,94 As disease duration increases, so does the likelihood of hospitalization and nursing home placement, underscoring the growing difficulty of managing care at home. ⁹³ Despite the recognized benefits, PC provision remains sparse, inconsistent, and largely limited to high-income countries (e.g., U.S., UK, Netherlands, Australia, Germany, Canada, Sweden). Referral to PC services often occurs only in the advanced or terminal stages of the disease.^{38,39,56,73,75,95,96}

Significant barriers hinder PC access, including inadequate information, education, and training for PwPs, caregivers, and HCPs. These gaps result in unmet needs, heightened disease burden, and inequities in care due to income, gender, and the lack of home-based services. Fragmented healthcare systems exacerbate these challenges, with poor integration of disciplines and inconsistent interactions between HCPs and patients undermining trust and continuity of care. Furthermore, HCPs often struggle to identify the optimal timing for PC referral and are insufficiently trained to address the comprehensive needs of PwPs and their caregivers.

This fragmented reality highlights the urgent need for innovative, patient-centred care delivery models. However, few studies have rigorously evaluated outpatient, multidisciplinary PC interventions.^69,81–83 These trials demonstrated that multidisciplinary care—incorporating neurology, nursing, social care, physical and occupational therapy, spiritual, and psychological support—can significantly improve QoL, reduce caregiver burden, and alleviate global symptom burden for advanced PwPs.^40,69,81,83 Additionally, these approaches reduced healthcare costs by mitigating preventable crises. Hence, improving access to PC for PwPs requires systemic changes, including better training for HCPs, integration of disciplines, and advocacy for evidence-based, multidisciplinary care models that address the complex and evolving needs of PwPs and their caregivers.

Despite advancements in recognizing the needs of PwPs, care delivery remains predominantly focused on motor symptom management.^46,47,61 PwPs report limited interactions with HCPs, centred mainly on pharmacological treatment, while non-motor needs significantly impacting QoL are often overlooked.^36,48 As the disease progresses, its impact extends beyond medical care to encompass social, spiritual, and financial challenges, as well as caregiver distress.^48,49,97

Education remains a critical barrier to implementing PC. PwPs, caregivers, and HCPs frequently lack adequate information about PC services and their application.^35,36,56 HCPs often fail to adopt a holistic approach to managing PD due to limited knowledge of PC principles.^25,43 Evidence suggests that educating allied HCPs improves care quality, reduces complications, and lowers healthcare costs. ⁹⁸ Emerging evidence-based educational programmes specifically address palliative care best practices in PD, targeting diverse audiences, including specialists, to enhance understanding of disease progression, prognosis, and care planning.^90,99–101 PC specialists have proven effective in managing non-motor complications, complex discharges, and ethical dilemmas, highlighting the need for stronger collaboration between neurology and PC disciplines.^25,36

This review identified multiple criteria for PC referral but no clear consensus. Criteria can be broadly categorized into:

1. Disease-related symptoms or complications, such as weight loss, recurrent infections, and cognitive or psychiatric changes.

2. Indicators of burdensome disease progression and increasing needs, including escalating impacts on PwPs and caregivers.

Informational, social, psychological, and spiritual needs often drive referrals, emphasizing a patient-centred rather than disease-centred approach.^18,102 Although several studies advocate for early PC referral, starting at diagnosis,^{13,25–28,30,35} limited evidence compares outcomes for early versus late PC initiation. Routine evaluations and open dialogues between HCPs, PwPs, and caregivers can help tailor PC interventions and determine the appropriate timing. ¹⁰³

ACP is vital for addressing long-term care preferences, yet discussions often occur too late. Early initiation of ACP is recommended to mitigate the risks associated with cognitive decline, apathy, and depression, which impede communication and decision-making.^28,36 Annual assessments of readiness for ACP discussions are suggested to ensure these conversations occur proactively rather than during crises like hospitalizations.^33,36

Evidence shows that ACP documentation influences end-of-life decisions, increasing the likelihood of PwPs choosing comfort measures over life-sustaining treatments and dying in their preferred setting, such as hospice or home. For example, individuals with documented HCP orders for life-sustaining treatment were half as likely to die in inpatient facilities compared to those without such documentation. ²⁸

Integrating PC early in the disease trajectory requires improving educational efforts, enhancing multidisciplinary collaboration, and tailoring care to individual needs. Addressing these gaps can support PwPs and caregivers, improve QoL, and align care delivery with patient preferences across all stages of the disease.

Limitations

This systematic review has several limitations that should be acknowledged. The primary limitation is that many of the included studies did not directly address the specific research questions posed in this review.

First, indicators for timely access to palliative care were often not explicitly mentioned in the included studies, requiring interpretation to extract relevant findings. Second, there is a notable lack of research examining organizational aspects at the meso and macro levels. Instead, the findings included in this review were identified as relevant organizational factors and integrated to provide an organization-specific perspective, raising questions about the representativeness of the results.

Third, the distinction between palliative care services and multi-professional teams specialized in the care of PwPs is not always clearly defined in the literature. While it is evident that multi-professional teams provide a holistic approach to meeting the needs of PwPs and their caregivers, these teams are not always comprised of specialists in palliative care.

Future research should focus on exploring palliative care for PwPs from an organizational perspective and on generating stronger evidence to guide clinical practice effectively.

Conclusions

In conclusion, the multifaceted and heterogeneous nature of PD underscores the need for a comprehensive, patient-centred approach to care that emphasizes the early integration of PC principles. Achieving personalized and holistic care requires the active involvement of a multidisciplinary team, including PC specialists, to address the complex physical, emotional, social, and spiritual needs of PwPs and their families.

Enhanced coordination of care and effective collaboration among the various healthcare providers involved in PD management are critical for improving care continuity and outcomes. Additionally, prioritizing education and training on PC for PwPs, caregivers, and healthcare professionals is essential to enhance the overall quality of care and QoL.

Implementing these strategies not only improves the quality of care but also empowers PwPs to actively participate in determining their care preferences, fostering a more patient-centred approach throughout the disease trajectory.