Abstract
Background
Global aging makes polypharmacy in older adults a critical concern. Pharmacist-led deprescribing shows promise, but lacks routine implementation. Japan introduced “the Medication Adjustment Support Fee (the Adjustment Fee)” in 2018 for deprescribing medications in patients with polypharmacy based on pharmacists’ recommendations.
Objective
We aimed to investigate: (1) medication distribution among older patients; (2) medications most frequently deprescribed based on pharmacists’ recommendations; and (3) factors associated with successful deprescribing.
Methods
This retrospective study analysed patients aged ≥ 65 years who had prescriptions dispensed for ≥ 60 days from 2069 community pharmacies (April 2020–September 2023). Eligibility for the adjustment fee required six or more oral medications for ≥ 4 weeks, with pharmacists receiving remuneration when two or more medications were deprescribed and sustained for ≥ 4 weeks. We examined: (1) medication distribution in older patients; (2) most frequently deprescribed medications based on pharmacists’ recommendations; and (3) factors associated with deprescribing using multi-level logistic regression.
Results
Amongst 1,458,323 older patients, 36.9% (537,884) met the eligibility criteria for the adjustment fee, but only 0.08% had medications deprescribed based on pharmacist recommendations. At the pharmacy level, 10% of pharmacies (213/2069) claimed the fee at least once. The most frequently deprescribed medications were rebamipide (0.05%), mecobalamin (0.06%) and magnesium oxide (0.02%). Older age, higher number of medications taken, presence of a family pharmacist, and longer evaluation periods were significantly associated with claiming for the adjustment fee (p < 0.001 for all).
Conclusions
Pharmacist-led deprescribing is infrequently implemented. Future studies could investigate the potential of strengthened incentives, enhanced collaboration, and robust protocols to optimize medication management in older adults.
Key Points
| Among 1.4 million older patients, only 437 had medications deprescribed based on pharmacist recommendations. |
| Low-risk medications like herbal medicines and vitamins were more frequently deprescribed than high-risk medications. |
| Family pharmacist (exclusive, continuous care) and longer evaluation periods significantly increased deprescribing likelihood. |
Introduction
With the global aging population, managing the health of older adults has become a priority in many countries. Older adults often experience physiological decline and multiple chronic diseases, which result in the need to take multiple medications [1]. Polypharmacy, defined as the use of multiple medications, increases the risk of adverse drug events such as falls and readmission, which can significantly impact the quality of life in older adults [2]. A key strategy in addressing inappropriate polypharmacy is deprescribing, which is a process of withdrawal of an inappropriate medication (one in which the risks of harm outweigh the benefits in the individual including high risk and unnecessary medications), supported by a healthcare professional with the goal of improving outcomes [3]
Previous research demonstrated that pharmacists can promote deprescribing in primary care settings through collaboration with prescribers to optimize pharmacotherapy [4–6]. However, much of this evidence comes from controlled clinical studies, with limited data on the implementation of pharmacist-led deprescribing in routine practice. Experiences and policy initiatives from countries with advanced aging populations are particularly valuable as references for other nations.
Japan, one of the most rapidly aging countries globally, has faced significant challenges in managing the care of older adults [7, 8]. While community pharmacy reimbursement in Japan includes multiple fees for various pharmacist services such as prevention of duplicate prescriptions or drug–drug interactions, the Ministry of Health, Labour and Welfare introduced a specific “Medication Adjustment Support Fee (hereafter Adjustment Fee)” in 2018, specifically targeting inappropriate polypharmacy through measurable medication reduction [9, 10]. This targeted approach reflects the policy recognition of polypharmacy as a critical concern requiring focused intervention.
Under the Adjustment Fee policy, community pharmacists are required to: (1) confirm patient preferences regarding deprescribing; (2) assess medication adherence and potential adverse effects with reference to national guidelines [7, 8]; and (3) submit written recommendations for deprescribing to prescribers typically by e-mail for patients who have continuously taken six or more oral medications (i.e., polypharmacy) for at least 4 weeks. Pharmacists conduct these assessments based on dispensing records, patient interviews, and pharmacy medication histories, though they typically have limited access to detailed clinical information such as laboratory data or diagnostic details unless patients voluntarily share this information. The pharmacists receive additional remuneration (1250 yen or approximately 8 USD) when at least two medications are actually deprescribed and sustained for 4 weeks or more following their recommendations, with implementation confirmed through subsequent prescription reviews.
In addition, to support comprehensive medication management, Japan introduced the “family pharmacist” system in 2016, which allows patients to designate a specific pharmacist for continuous and personalized pharmaceutical care [11, 12]. Patients who register with a family pharmacist pay an additional copayment (typically 30–100 yen, approximately 0.2–0.7 USD per prescription, depending on their insurance coverage rate) in exchange for this enhanced level of personalized pharmaceutical care. This system aims to improve medication safety through enhanced continuity of care, particularly important given that Japanese patients often receive prescriptions from multiple specialists at different institutions.
Previously, it was extremely difficult to conduct a large-scale investigation using pharmacy record data because of the challenges of integrating records from multiple pharmacies. However, the emergence of a cloud-based electronic pharmacy record system that centrally manages these data has now enabled comprehensive analysis of pharmacist-led deprescribing interventions through large-scale real-world data. This study aimed to investigate the deprescribing recommendations made by community pharmacists in Japan for older outpatients with polypharmacy. Specifically, it investigated the following: (1) the distribution of the number of medications taken by older patients; (2) medications most frequently deprescribed based on pharmacists’ recommendations; and (3) factors associated with deprescribing of medications.
Methods
Study Design, Setting, and Participants
This retrospective cohort study utilized electronic medication history data from 2069 community pharmacies, which continuously used the cloud-based system provided by Kakehashi Inc. between 1 April, 2020, and 30 September, 2023 [13]. All data were deidentified prior to analysis. To investigate the distribution of the number of medications taken by older patients, patients aged 65 years or older who had prescriptions dispensed at the same pharmacy for a total of 60 days or more were included in analysis. This cohort identified patients with long-term medication use and excluded short-term acute care prescriptions. Only oral medications with each prescription having a duration of at least 14 days (excluding as-needed medications) were analyzed in accordance with the Adjustment Fee criteria, focusing on medications for chronic disease. To ensure anonymity because of the small numbers of the oldest old, patients aged 90–100 years were recorded as 90, and those aged 101 years or older were excluded. Ethics approval for this study was obtained; details are provided in the Declarations section.
Considering that Japan has no general practitioner system and patients can visit different clinics for different medical specialties, in order to count the number of medications for chronic disease as accurately as possible, we applied the concept of the daily polypharmacy possession rate [14]. The daily polypharmacy possession rate estimates the proportion of days a patient possesses medications by considering the presence or absence of multiple medications on each day during the study period. In the present study, we considered a patient to “possess,” or be “taking,” a medication from the dispensing date through the prescribed duration. For example, if a medication was dispensed on 1 January with a 30-day supply, it was considered as being taken from 1 January to 30 January. If the patient received the same medication again prior to the end of the 30-day supply (e.g., on January 25), the new 30-day supply was considered to start from 1 February, accounting for overlapping medication possession. Conversely, if no subsequent prescription for that medication was dispensed after 1 January, the medication was considered discontinued from 1 February onwards (i.e., after the initial 30-day supply was exhausted), though the reason for discontinuation could not be determined from dispensing records. Using this approach, the number of medications possessed each day was calculated and then the combination of medications most frequently possessed during the study period was identified. This combination was operationally defined as the patient’s typical medication regimen that was used to evaluate the distribution of the number of medications taken per person.
To investigate medications most frequently deprescribed, and factors associated with deprescribing of medications based on pharmacists’ recommendations, patients who had ever continuously taken six or more oral medications for at least 4 consecutive weeks during the study period were identified as meeting the eligibility criteria for the Adjustment Fee [15]. It is important to note that this eligibility criterion for the Adjustment Fee differs from the criteria for ‘typical medication regimen’ analysis described above. A patient could be eligible for the Adjustment Fee if they took the six or more oral medications for ≥ 4 consecutive weeks at any time during the study period, even if their most predominant medication pattern was fewer than six oral medications. In contrast, patients were classified as having polypharmacy in the typical regimen analysis only if their predominant pattern over the entire study period was six or more oral medications.
After combining the date of claiming the Adjustment Fee and dispensing records, deprescribed medications were identified through the following process. Two research pharmacists (NS and AO) independently reviewed dispensing records up to 12 months prior to each fee claim date. They first confirmed patients were taking six or more oral medications that had been continuously prescribed for at least 4 weeks. They then identified two medications that were deprescribed for at least 4 weeks prior to the fee claim date. When more than two medications were deprescribed at the same time, all of these medications were considered to be deprescribed based on pharmacists’ recommendation, rather than limiting to only two medications. The agreement between the two researchers was assessed using the Jaccard coefficient, which measures the similarity between two sets by dividing the size of the intersection by the size of the union of the sets, providing a value between 0 (no agreement) and 1 (perfect agreement) [16]. Any discrepancies were resolved through discussion with another research pharmacist (KF) to reach consensus. Additionally, to characterize the types of medications deprescribed, all deprescribed medications were classified according to the 2019 Beers Criteria to identify whether they were listed as potentially inappropriate medications.
Statistical Analysis
Data were summarized using descriptive methods, including the median and interquartile range (IQR). To investigate factors associated with deprescribing of medications based on pharmacists’ recommendations, multi-level logistic regression analysis was conducted including pharmacies as a random effect and patient age, sex, number of medications, and the presence of a family pharmacist as fixed effects in the model. The family pharmacist variable indicated whether the patient had a registered family pharmacist who provided continuous medication management under this system. All variables included in the analyses had complete data with no missing values. Data manipulation and statistical analyses were performed using Python version 3.8.8 (Python Software Foundation) and R version 3.6.1 (R Foundation). Two-sided p-values < 0.05 were considered statistically significant.
Results
The study included a total of 1,458,323 patients from 2069 pharmacies from across 46 of Japan’s 47 prefectures (all except Toyama Prefecture). Regarding pharmacy characteristics, participating pharmacies had a median of 1.0 pharmacy per owner (IQR: 1.0–2.0), indicating a predominance of independent pharmacies. The median number of full-time pharmacists (those working ≥ 32 h per week) was 2.0 (IQR: 1.0–4.0), part-time pharmacists was 5.0 (IQR: 2.0–10.0), and the median number of monthly prescriptions handled was 1333 (IQR: 861–1985). Regarding patient characteristics, the median age was 75.0 years (IQR: 70.0–81.0), and the median number of oral medications regularly taken was 2 (IQR: 1.0–5.0). Of the patients, 56.1% were female and 2.9% had an exclusive, continuous family pharmacist (Table 1).
Table 1.
Patients’ characteristics (N = 1,458,323)
| Items | Count |
|---|---|
| Age, years, median (IQR) | 75.0 (70.0–81.0) |
| Female (%) | 818,648 (56.1) |
| Oral medications ≥ 6, (%) | 285,214 (19.6) |
| Smoking = yes (%) | 66,173 (4.5) |
| Presence of family pharmacist (%) | 41,695 (2.9) |
| Number of oral medicines, median (IQR) | 2.0 (1.0–5.0) |
| Evaluation periods, days, median (IQR) | 744.0 (308.0–1187.0) |
| Medication Adjustment Support Fee | |
| Number of patients eligible for the fee (%) | 537,884 (36.9) |
| Number of claims for the fee | 452 |
| Number of patients claimed for the fee (%) | 437 (0.081) |
IQR interquartile range
Analysis of the number of medications taken by patients revealed that 19.6% of patients (n = 285,214) took six or more medications (polypharmacy). The proportion of patients with polypharmacy per community pharmacy was a median of 20.4% (IQR: 14.3–25.9). An age-stratified analysis demonstrated a decline in the proportion of patients taking three or fewer medications with increasing age, while the proportion of patients taking four or more medications increased steadily (Fig. 1). Specifically, the proportion of patients with polypharmacy increased from approximately 12.5% at age 65 years to 29.3% at age 90 years or older. Similarly, the prevalence of hyper-polypharmacy (ten or more medications) rose from 1.6% at age 65 years to 7.1% at age 90 years or older. These findings highlight an age-associated increase in polypharmacy and hyper-polypharmacy, underscoring the growing complexity of medication regimens in older age groups.
Fig. 1.
Prevalence of polypharmacy among older adults
Among the 1,458,323 patients, 36.9% (537,884 patients) met the eligibility criteria for the Adjustment Fee. Among these eligible patients, those with family pharmacists (n = 37,972, 7.1%) were slightly older (median age 79.0 vs 77.0 years), more likely to be female (60.5% vs 52.9%), and had longer evaluation periods (median 893 vs 633 days) compared with those without family pharmacists (n = 499,912), though the medication burden was similar (median five medications for both groups). The most commonly prescribed medications among the 537,884 patients included amlodipine (36.3%), magnesium oxide (30.1%), and rosuvastatin (19%). Among Beers Criteria-listed medications, proton pump inhibitors such as lansoprazole (17.9%) and esomeprazole (14.7%) were most frequently prescribed (Table 2). Of the 537,884 patients, only 437 patients (0.081%) had their medications deprescribed based on pharmacists’ recommendations (452 claims in total). Interestingly, in 15 cases, the pharmacies claimed the Adjustment Fee two times for the same patients (i.e., four medications were deprescribed in total). At the pharmacy level, only 10% of pharmacies (213 pharmacies) claimed the Adjustment Fee at least once during the study period.
Table 2.
Most commonly prescribed medications and Beers Criteria-listed medications among patients eligible for the Adjustment Fee (N = 537,884)
| No. | All medicines | Beers-listed medicines | ||
|---|---|---|---|---|
| Names | Frequency | Names | Frequency | |
| 1 | Amlodipine | 195468 (36.3%) | Lansoprazole | 96116 (17.9%) |
| 2 | Magnesium oxide | 161921 (30.1%) | Esomeprazole | 78833 (14.7%) |
| 3 | Rosuvastatin | 102070 (19%) | Nifedipine | 55747 (10.4%) |
| 4 | Lansoprazole | 96116 (17.9%) | Rabeprazole | 49421 (9.2%) |
| 5 | Acetylsalicylic acid | 93531 (17.4%) | Zolpidem | 42632 (7.9%) |
| 6 | Rebamipide | 87561 (16.3%) | Glimepiride | 32497 (6%) |
| 7 | Esomeprazole | 78833 (14.7%) | Doxazosin | 20179 (3.8%) |
| 8 | Vonoprazan | 77036 (14.3%) | Triazolam | 11452 (2.1%) |
| 9 | Bisoprolol | 75265 (14%) | Omeprazole | 11190 (2.1%) |
| 10 | Febuxostat | 72403 (13.5%) | Alprazolam | 9374 (1.7%) |
At the medication level, 1012 unique medications were deprescribed based on pharmacists’ recommendations. The Jaccard coefficient with a mean of 0.87 (standard deviation: 0.27) indicated a very high level of similarity in the identification process for deprescribed medications between the reviewers. As shown in Table 3, the most frequently deprescribed medications were the gastroprotective agent rebamipide (41/87,561, 0.05%), followed by the vitamins/supplements mecobalamin (39/64,476, 0.06%) and magnesium oxide (26/151,464, 0.02%). Classification of deprescribed medications according to the 2019 Beers Criteria revealed that only 6.7% (68/1,012) of deprescribed medications were listed as potentially inappropriate medications in older adults. The most frequently deprescribed Beers Criteria-listed medications included lansoprazole (9/96,116, 0.009%), zolpidem (8/42,632, 0.019%), esomeprazole (7/78,833, 0.009%), and rabeprazole (6/49,421, 0.012%).
Table 3.
Top ten most frequently deprescribed medications following pharmacist recommendations
| No. | All medicines | Beers-listed medicines | ||
|---|---|---|---|---|
| Names | Frequency | Names | Frequency | |
| 1 | Rebamipide | 41/87561 (0.0468%) | Lansoprazole | 9/96116 (0.0094%) |
| 2 | Mecobalamin | 39/64476 (0.0605%) | Zolpidem | 8/42632 (0.0188%) |
| 3 | Magnesium oxide | 26/151464 (0.0172%) | Esomeprazole | 7/78833 (0.0089%) |
| 4 | Mosapride | 21/33480 (0.0627%) | Rabeprazole | 6/49421 (0.0121%) |
| 5 | Carbocisteine | 19/38751 (0.049%) | Fesoterodine | 5/5070 (0.0986%) |
| 6 | Betahistine | 16/21947 (0.0729%) | Nifedipine | 5/55747 (0.009%) |
| 7 | Nicotinic acid and derivatives | 16/15798 (0.1013%) | Glimepiride | 3/32497 (0.0092%) |
| 8 | Teprenone | 16/17547 (0.0912%) | Hydroxyzine | 3/1481 (0.2026%) |
| 9 | Ambroxol | 14/32706 (0.0428%) | Diazepam | 2/4712 (0.0424%) |
| 10 | Celecoxib | 14/45676 (0.0307%) | Glibenclamide | 2/1828 (0.1094%) |
The denominator represents the number of patients among the 537,884 eligible patients who were taking each specific medication during their evaluation period for the Adjustment Fee. The numerator represents the number of patients for whom the medication was deprescribed following pharmacist recommendations. Percentages indicate the deprescribing rate for each medication
A multi-level logistic regression analysis revealed that age (adjusted odds ratio [95% confidence intervals] = 1.05 [1.03–1.07]), the number of medications (1.11 [1.07–1.15]), presence of the family pharmacist (2.75 [2.09–3.64]), and evaluation periods (1.52 [1.33–1.73]) were statistically significantly associated with claiming for the Adjustment Fee (p < 0.001 for all, Table 4).
Table 4.
Factors associated with deprescribing of medications based on pharmacists’ recommendations in a multi-level logistic regression analysis
| Variables | Adjusted odds ratio (95% confidence intervals) |
|---|---|
| Age | 1.05 (1.03–1.07)* |
| Sex | 1.08 (0.86–1.35) |
| Number of oral medicines | 1.11 (1.07–1.15)* |
| Presence of family pharmacist = yes | 2.75 (2.09–3.64)* |
| Evaluation periods for the fee | 1.52 (1.33–1.73)* |
*p < 0.001
Discussion
In this large-scale study of over 1.4 million older adults receiving care at 2069 community pharmacies, we used a large-scale dataset managed via a cloud-based electronic pharmacy record system to investigate the prevalence of polypharmacy and the current status of pharmacist-led deprescribing interventions. The present study observed a notable burden of polypharmacy, with nearly one in five patients (19.6%) consistently taking six or more medications. Importantly, although 36.9% of patients met eligibility criteria for the Adjustment Fee (i.e., six or more continuous oral medications for at least 4 weeks), only 0.081% of these individuals had two medications deprescribed based on pharmacist recommendations. At the pharmacy level, only 10% of pharmacies claimed this fee at least once during the study period. Given that the proportion of older adults with polypharmacy was relatively consistent across pharmacies (approximately 20%), these findings indicate a persistent gap between the potential need for deprescribing inappropriate medications in older adults and the actual implementation of pharmacist-led interventions in routine practice.
The observed polypharmacy prevalence of 19.6% in this study is broadly consistent with previous study findings in Japan and lower than those of international studies, acknowledging differences in the definition of polypharmacy, counting methods, and publication year. Japanese community studies that applied the six or more medicines threshold, counting all medications prescribed monthly, reported a 39% prevalence in people aged ≥ 65 years [17], whereas another cohort study using the five or more medicines threshold reported a prevalence of 23.3% among those aged ≥ 65 years [18]. Internationally, systematic reviews reported the polypharmacy (five or more medicines) prevalence of 45% amongst those aged ≥ 65 years [19, 20]. Country-specific studies showed substantial variation: 19.0% in Sweden [21], 25.5% in Switzerland [22], 36.8% in the USA, [23] and 41.8% in South Korea [24]. Given that our study applied a stricter criteria by limiting analysis to six or more oral medications for ≥ 60 days, the observed prevalence may be more conservative compared with studies using broader inclusion criteria.
In this study, although this reimbursement was introduced in 2018 to encourage pharmacists’ deprescribing activities, the rate of claiming the Adjustment Fee was only 0.08%. Notably, while the proportion of patients with polypharmacy was relatively consistent across pharmacies (approximately 20%), the Adjustment Fee was claimed by only 10% of pharmacies during the study period, suggesting that many older adults with potentially inappropriate medications may remain unaddressed. This substantial gap between need and implementation warrants careful examination of potential barriers. Previous research has identified multiple barriers that healthcare professionals face when attempting deprescribing in older adults with polypharmacy, including lack of knowledge and confidence, time constraints, limited access to comprehensive patient information, and the absence of standardized deprescribing protocols [25–32]. In the context of the Adjustment Fee specifically, the reimbursement amount (1250 yen, approximately 8 USD) may not adequately compensate for the substantial effort required. These potential barriers may contribute to the extremely low claim rate and substantial variability in program uptake across pharmacies.
Our analysis using the 2019 Beers Criteria confirmed this pattern, showing that only 6.7% of deprescribed medications were listed as potentially inappropriate medications for older adults, despite these medications being commonly prescribed in the eligible population. For example, proton pump inhibitors such as lansoprazole and esomeprazole were prescribed to 17.9% and 14.7% of eligible patients, respectively, yet their deprescribing rates remained very low (0.009% for both). This discrepancy may highlight substantial missed opportunities for addressing potentially inappropriate medications in older adults through pharmacist-led interventions. These findings align with the global challenge of insufficient implementation of deprescribing in clinical care. A previous study reported that while deprescribing has the potential to improve patient outcomes, the majority of medications deprescribed by the healthcare providers’ intervention tend to be those that are relatively easy to stop, such as laxatives or vitamin supplements [33]. This pattern may reflect pharmacists’ limited access to detailed clinical information such as diagnosis or laboratory data in community pharmacy settings, leading to more cautious recommendations about deprescribing high-risk medications and more conservative deprescribing recommendations for medications perceived as safer to discontinue [34, 35]. Improving pharmacists’ access to comprehensive clinical information could empower them to more confidently assess the appropriateness of high-risk medications and potential adverse drug withdrawal events.
A multi-level logistic regression analysis revealed that patients’ age, the number of medications taken, presence of a family pharmacist, and the evaluation period were significantly associated with the Adjustment Fee claims. In other words, a greater number of medications increased the need for deprescribing recommendations, while having a designated family pharmacist facilitated a deeper understanding of a patient’s medication regimen, making deprescribing recommendations more likely. Additionally, the finding that longer evaluation periods for the Adjustment Fee are associated with higher claim rates indicates that extended engagement with the pharmacy provides more opportunities for pharmacists to optimize medication regimens, collaborating with prescribers. These results highlight the potential benefits for expanding the family pharmacist model and establishing long-term follow-up structures to improve the effectiveness of polypharmacy interventions. Future research examining how such time-related factors and continuous pharmacist involvement influence patient outcomes and healthcare economics could establish a more robust evidence-based framework for pharmacist-led deprescribing interventions.
This study has several strengths. We utilized a large-scale dataset from a cloud-based electronic pharmacy record system, enabling comprehensive analyses that were previously limited by the logistical challenges of consolidating pharmacy records. In particular, because the number of pharmacies that actually claimed the Adjustment Fee and the total number of claims were notably low, analyzing these rare events would have been nearly impossible without a sufficiently large dataset. However, this study also has several limitations. One key limitation of this study is that the Adjustment Fee requires the deprescribing of at least two medications, meaning that cases with only one medication deprescribed were not captured in our analysis, potentially leading to an underestimation of the true prevalence of pharmacist-led deprescribing interventions. Additionally, we did not evaluate the appropriateness of deprescribed medications owing to the lack of pharmacists’ clinical documentation and detailed clinical data, such as diagnostic and laboratory information. Future research examining the clinical appropriateness of deprescribing decisions, including assessment of drug–drug interactions, would provide valuable insights for optimising pharmacist-led deprescribing interventions. Furthermore, this study relied on dispensing records to estimate medication possession rather than direct assessment of medication adherence, and we could not verify whether patients actually took the medications as prescribed. Another limitation is that patients who used multiple pharmacies may have been taking additional medications not captured in our analysis, potentially affecting the accuracy of medication counts and polypharmacy prevalence estimates. Our dataset did not include pharmacists’ written deprescribing recommendation documents or physician consent records. Instead, we relied on billing codes and dispensing records to identify cases. Therefore, we could not fully verify the causal relationship between pharmacist recommendations and deprescribing outcomes for individual cases. Furthermore, because this study included pharmacies using a specific cloud-based system in Japan’s unique health insurance and cultural context, the findings may not be fully representative of all community pharmacies in Japan or generalizable to other countries.
Conclusions
Using a large-scale database of community pharmacies, this study evaluated the extent of polypharmacy and pharmacist-led deprescribing interventions for older adults in Japan. Despite many older adults consistently taking six or more medications, the claim rate for the Adjustment Fee remained very low, indicating limited implementation of pharmacist-led deprescribing in practice. Broader use of standardised deprescribing recommendation and closer patient-pharmacist-prescriber collaboration may facilitate pharmacist-led deprescribing of inappropriate polypharmacy in older adults in primary care.
Funding
Open Access funding enabled and organized by CAUL and its Member Institutions. No funding was received to assist with the preparation of this article.
Declarations
Conflicts of Interest/Competing Interests
Kazuki Kushida reports serving as an advisor to SUGI Pharmacy. Sarah N. Hilmer is an editorial board member of Drugs and Aging. Sarah N. Hilmer was not involved in the selection of reviewers or editorial decisions for this paper. Kenji Fujita, Noriko Sato, Ayumi Okizaki, Ruri Endo, Maho Taguchi, Timothy F. Chen, and Tomoya Kudo have no conflicts of interest that are directly relevant to the content of this article.
Ethics Approval
This study was approved by the Yokohama University of Pharmacy Research Ethics Committee on 25 March, 2024 (C24001A, study period: 25 March, 2024 to 31 December, 2025). The study was conducted in accordance with the ethical standards of the 1964 Declaration of Helsinki and its later amendments.
Consent to Participate
For the electronic pharmacy record data extracts for this study period, the research team requested a waiver of consent in view of the large sample size.
Consent for Publication
Not applicable.
Availability of Data and Material
The data are not publicly available because of privacy or ethical restrictions.
Code Availability
The analytic code used to support the findings in this study is available from the corresponding author upon reasonable request.
Authors’ Contributions
KF had full access to all the data in the study and takes responsibility for the integrity of the data and the accuracy of the data analysis. Conception and design: KF, NS, AO, RE, KK, TK. Data acquisition: RE, AO, MT, TK. Statistical analysis: KF, NS, AO. Drafting of the manuscript: KF. Revision of the manuscript: all authors. Supervision: SH, TFC, KK. All authors read and approved the final manuscript.
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