The Effects of Short-term Intensive Inpatient Rehabilitation on Motor, Non-motor, and Neuropsychological Functions in Parkinson’s Disease

ABSTRACT

Objectives:

In previous studies, intensive rehabilitation for patients with Parkinson’s disease (PD) has been implemented in both outpatient and inpatient settings, with varying durations across studies. Among these, most inpatient intensive rehabilitation programs are conducted for 1 month, with few reports evaluating detailed changes in neuropsychological functions. In this study, we investigated the effect of a short-term intensive inpatient rehabilitation program lasting 2 or 3 weeks on motor and non-motor symptoms, motor ability, and neuropsychological functions in hospitalized patients with PD.

Methods:

We enrolled 15 patients with PD (7 men, 8 women; mean age, 75.1±6.5 years; Hoehn and Yahr stages III/IV, 12/3). The rehabilitation program included physical, occupational, and speech-language therapies and was implemented daily for 2 or 3 weeks. Motor and non-motor symptoms as well as motor abilities were assessed using the Movement Disorders Society Unified Parkinson’s Disease Rating Scale, Functional Independence Measure, Parkinson’s Disease Questionnaire-39, and other assessments. Neuropsychological functions were evaluated using Japanese versions of the Mini-Mental State Examination and Frontal Assessment Battery and using the CogEvo (computerized cognitive function evaluation) tool. Scores were compared before and after intervention.

Results:

This short-term inpatient rehabilitation therapy significantly improved motor and non-motor symptoms, motor abilities, reality orientation as assessed by CogEvo, and the overall quality of life.

Conclusions:

The results of this study suggest that short-term intensive rehabilitation in patients with PD may achieve favorable outcomes even within a limited timeframe. Further discussion of the appropriate duration of inpatient rehabilitation for patients with PD is warranted.

INTRODUCTION

Parkinson’s disease (PD) is a slowly progressive disorder characterized by the degeneration of dopaminergic neurons in the substantia nigra and striatal system. Although PD is primarily diagnosed based on the identification of motor and non-motor symptoms, autonomic dysfunction and psychiatric or cognitive impairments are frequently observed. These diverse clinical manifestations are believed to stem from the extensive degeneration of the nervous system, affecting both the peripheral and central components.¹⁾ The current treatments for PD include pharmacological therapy, surgical interventions, and rehabilitation. Recent studies have reported the efficacy of intensive rehabilitation for both the motor and non-motor symptoms of PD.^2,3,4,5) Previous reports have documented rehabilitation strategies performed in either an outpatient or inpatient setting, and the durations of the interventions varied. Among these, most inpatient-intensive rehabilitation programs were implemented for 1 month, and few studies have included detailed neuropsychological examinations to evaluate improvements in neuropsychological functions.

In the present study, we investigated the effects of a short-term, intensive inpatient rehabilitation program lasting 2 or 3 weeks for patients with PD at our hospital. We examined motor and non-motor symptoms, motor ability as well as detailed changes in neuropsychological functions using the CogEvo (computerized cognitive function evaluation) tool⁶⁾ and other conventional neuropsychological examinations.

MATERIALS AND METHODS

This study recruited patients with PD between November 2021 and February 2023 from the neurology outpatient clinic at Showa University Fujigaoka Hospital, and was conducted at Showa University Fujigaoka Rehabilitation Hospital in Kanagawa Prefecture, Japan. The inclusion criteria were as follows: (1) a confirmed diagnosis of PD; (2) a history of drug treatment for more than 3 years; and (3) being informed about the study procedures and providing written informed consent before participating in the assessment. The exclusion criteria were as follows: (1) patients with PD who required total assistance with activities of daily living (ADL) and (2) those with dementia or treatment-resistant psychiatric symptoms.

Fifteen patients with PD (seven men, eight women; mean age 75.1 ± 6.5 years) were enrolled in the study. Clinical details are presented in Table 1. Twelve patients were at Hoehn and Yahr stage III, and three were at stage IV. The mean levodopa equivalent dose was 575 ± 214 mg/day, and the mean time since diagnosis was 5.5 ± 3.1 years. The care need level was assessed on two scales: “Assistance Necessary” (two levels) and “Care Necessary” (five levels), with higher values indicating greater severity. The values for each scale are shown in Table 1.

Table 1.  Case list.

Case	Age (years)	Sex	Hoehn and Yahr stage	Levodopa equivalent (mg/day)	Time since diagnosis (years)	Hospitalization period (weeks)	Care need level
1	77	Female	IV	700	7	3	CN2
2	86	Male	III	550	7	2	CN2
3	63	Female	III	200	1	3	AN1
4	69	Male	III	825	11	3	CN4
5	74	Female	III	437.5	7	2	Not applied
6	72	Female	III	350	5	2	AN2
7	62	Male	III	500	2	2	AN2
8	81	Female	III	600	3	2	CN1
9	76	Male	III	350	5	2	CN3
10	73	Female	III	960	10	2	Not applied
11	78	Female	IV	950	8	3	CN2
12	80	Male	IV	700	Unknown	2	CN4
13	81	Male	III	400	2	2	CN2
14	81	Female	III	600	3	2	CN1
15	73	Male	III	500	Unknown	3	CN1
Mean±SD	75.1±6.5			575±214	5.5±3.1	2.3±0.4

AN, Assistance necessary; CN, Care necessary; SD, standard deviation.

The short-term intensive rehabilitation program at our hospital was conducted over 2 or 3 weeks, with two or three sessions per day (40 min per session), according to the patient’s preferences. Patients were typically hospitalized for 2 weeks, although five patients remained in hospital for 3 weeks. Physical therapy included one-legged standing exercises, gait training to address gait disorders such as wiggling and shuffling gait caused by muscle rigidity, and spinal column range of motion and balance training to improve postural reflexes. Occupational therapy involves upper limb manipulation and fine motor skill training, along with ADL tailored to an individual’s needs. Speech and language therapy involves voice, articulation, evaluation, and training for swallowing difficulties. Furthermore, the patients were instructed to perform self-training at their discretion during their free time while hospitalized and to continue after discharge at any preferred frequency (Table 2). No changes or additions to medications were made during hospitalization.

Table 2.  Self-training instructions.

Exercise items	Specific actions
Finger exercises	Finger flexion and extension, finger folding, pinching, and wrist rotation training, as well as forearm pronation and supination training
Bed exercises	Bicycle exercise, trunk rotation, hip lift, glute stretch, leg raises
Chair exercises	Torso twisting, pelvic tilt, lateral step, arm raises, shoulder blade circles
Standing exercises	Lateral step, forward step, foot tapping, weight shifting, stretching exercise, squat
Eye exercises	Eye movements in all directions

To comprehensively evaluate the effects of the rehabilitation program, multiple assessment tools were employed. The Movement Disorders Society Unified Parkinson’s Disease Rating Scale (MDS-UPDRS),⁷⁾ a comprehensive tool used to assess the severity and progression of PD, and the Japanese version of the Parkinson’s Disease Questionnaire-39 (PDQ-39),⁸⁾ a disease-specific measure used to assess the health status and quality of life (QOL), were used as assessment tools. Specifically, the following domains were assessed to evaluate various aspects of PD: motor symptoms (MDS-UPDRS Part III), non-motor symptoms (MDS-UPDRS Part I, PDQ-39), treatment-related motor complications such as dyskinesia and wearing-off (MDS-UPDRS Part IV), motor ability [10-m walking speed and number of steps, Timed Up-and-Go test (TUG),⁹⁾ Short Physical Performance Battery (SPPB),¹⁰⁾ grip strength, muscle mass assessed using a Body Composition Analyzer (InBody S10), MDS-UPDRS Part II, Functional Independence Measure (FIM)]. In addition to these assessments, specific tools were utilized to evaluate neuropsychological function. To examine neuropsychological function, we employed CogEvo (Total Brain Care, Kobe, Japan), a commercially available computerized cognitive assessment tool that detects subtle changes in cognitive function (Reality orientation, Memory, Executive function, Visuospatial cognition, Attention) by measuring both accuracy and task completion time during gameplay. CogEvo was used in this study with acknowledgment of its commercial origin. It is composed of 14 different types of tasks, and the reliability and validity of the short version have been verified for older adults.^6,11) The tasks within CogEvo are as follows: (1) Reality orientation: questions regarding the date, day of the week, and the time at the time of testing are presented individually on the screen, and participants are asked to select the correct answer from multiple-choice options. (2) Memory: participants are asked to touch circular stimuli on the screen in the same order in which they are illuminated. (3) Executive function: participants are required to navigate through numbers displayed randomly in multiple boxes on the screen, following them in sequential order to reach the goal. (4) Visuospatial cognition: participants are asked to select the figure that matches the shape presented at the center of the screen from among six surrounding figures. (5) Attention: participants are asked to touch numbers, letters, and alternating numbers and letters presented on the screen in sequential order. In addition, we used the Japanese versions of the Mini-Mental State Examination (MMSE-J) and Frontal Assessment Battery (FAB)¹²⁾ to screen for neuropsychological and frontal lobe function, respectively. Scores were compared before and after intervention. All assessments were performed by the same evaluator before and after the short-term intensive rehabilitation program, and all were conducted during the patients’ “on” state to ensure consistency in evaluating motor function.

This study was approved by the Showa University Clinical Research Review Board (approval no. 21–067-B) in November, 2021. Statistical analyses were performed using EZR version 1.68.¹³⁾ The normality of each measurement was assessed using the Shapiro–Wilk test. Paired t-tests were used for data that met the normality assumption, whereas the Wilcoxon signed-rank test was used for data that did not meet the normality assumption. Statistical significance was recognized for P < 0.05.

RESULTS

The results of patient assessments are summarized in Table 3. For motor symptoms, a significant improvement was observed in the total score of MDS-UPDRS Part III [38.8±10.2 (mean ± standard deviation) to 34.3±13, P=0.036]. For non-motor symptoms, a significant improvement was observed in the total score of MDS-UPDRS Part I [10.5 (6.5–13.5) to 5 (4.8–9.8), P=0.014]. Furthermore, QOL also demonstrated a significant improvement in the PDQ-39 (61±32.5 to 45.8±28.2, P=0.037). No significant change was observed in treatment-related motor complications, as assessed by MDS-UPDRS Part IV [4.0 (0–5.8) to 3.0 (0–5.3), P=0.423], indicating that dyskinesia and wearing-off remained stable during the intervention.

Table 3.  Overall assessment before and after rehabilitation intervention.

Assessment	Item	Admission value	Discharge value	P
Motor symptoms	MDS-UPDRS Part III (/132)	38.8±10.2	34.3±13	0.036*
Non-motor symptoms	MDS-UPDRS Part I (/52)	10.5 [6.5–13.5]	5 [4.8–9.8]	0.014*
	PDQ-39 (/156)	61±32.5	45.8±28.2	0.037*
Treatment-related complications	MDS-UPDRS Part IV (/24)	4.0 [0–5.8]	3.0 [0–5.3]	0.423
Motor abilities	10-m walking speed (s) 10-m walking step (steps)	10.8 [9.1–17.1] 20 [17–29.8]	10.1 [8.4–14.4] 18.3 [17–24.5]	0.116 0.405
	Right TUG (s) Left TUG (s)	14.6 [9.7–17.3] 12.3 [9.9–18.3]	10.7 [8.5–14.6] 12.1 [8.6–14.1]	0.007** 0.003**
	SPPB (/12)	9 [6–10]	11 [9–12]	0.008**
	Right grip strength (kg) Left grip strength (kg)	23.5±6.2 21.0±6.0	25.1±6.1 23.0±5.2	0.146 0.067
	Muscle mass (kg)	39.2±9.5	38.9±9.0	0.264
	MDS-UPDRS Part II (/52)	17.9±9.5	14.5±7.6	0.020*
	FIM total (/126)	101±15.1	106±14.0	0.011*
	FIM motor (/91)	67.4±14.1	72.3±13.4	0.010**
Cognitive functions	MMSE-J (/30)	28 [25.5–30]	29 [27–30]	0.677
	FAB (/15)	14.1±3.0	14.5±2.7	0.605
	FIM cognition (/35)	35 [33–35]	35 [33.5–35]	1.000

Data given as mean ± standard deviation or median [interquartile range].

^*P < 0.05; ^**P < 0.01.

Regarding motor ability, significant improvements were noted in median (interquartile range) scores for SPPB [9 (6–10) to 11 (9–12), P=0.008], the right TUG [14.6 (9.7–17.3) to 10.7 (8.5–14.6), P=0.007], and left TUG [12.3 (9.9–18.3) to 12.1 (8.6–14.1), P=0.003]. For ADL, significant improvements were observed in MDS-UPDRS Part II (17.9±9.5 to 14.5±7.6, P=0.020), the total FIM (101±15.1 to 106±14.0, P=0.011), and the FIM motor items (67.4±14.1 to 72.3±13.4, P=0.010).

For neuropsychological functions, as detailed in Tables 3 and 4, no improvement was observed in the MMSE-J, FAB, or the FIM cognition score. However, these scores were originally near the maximum. In contrast, CogEvo revealed a significant improvement in reality orientation [99.9 (81.4–101) to 104.1 (94.4–112), P=0.031]. No notable improvements were identified in other motor abilities not mentioned above, or neuropsychological functions except for reality orientation.

Table 4.  Evaluation of CogEvo before and after rehabilitation intervention.

CogEvo item	Admission value	Discharge value	P
Reality orientation	99.9 [81.4–101]	104.1 [94.4–112]	0.031*
Memory	110 [92.8–116]	109 [100–117]	0.2945
Executive function	101.0±17.5	102.4±20.7	0.6582
Visuospatial cognition	100.7±20.1	103.6±13.5	0.7043
Attention	99.2±16.4	98.4±18.5	0.6271

Data given as mean ± standard deviation or median [interquartile range].

^*P < 0.05.

DISCUSSION

In this study, we investigated the effects of short-term intensive rehabilitation lasting 2–3 weeks on motor and non-motor symptoms, motor ability, and neuropsychological functions in patients with PD. Generally, short-term intensive rehabilitation is performed in either an outpatient or inpatient setting. Outpatient rehabilitation allows patients to maintain their daily lives and may prevent a decline in ADL; however, some patients may be unable to attend frequent outpatient sessions. Conversely, inpatient rehabilitation allows high-frequency daily training that regulates a patient’s daily routine. However, during the time not spent on training, patients may spend a considerable amount seated in a chair. In the present study, activity monitors or wearable devices were not used to objectively assess patients’ physical activity levels outside of rehabilitation sessions. Incorporating objective monitoring tools such as activity trackers in future research may enable a more precise understanding of patients’ daily activity patterns and help clarify the relationship between physical activity and rehabilitation outcomes. Existing short-term intensive rehabilitation studies on PD, including the outpatient study of Krause et al.,²⁾ which involved 6–7 h per day of relaxation, physical therapy, speech therapy, and tai chi over 3 weeks, demonstrated improvements in motor (MDS-UPDRS Part III) and non-motor symptoms, as well as QOL (PDQ-39). These findings support our results, indicating that both the duration of routine rehabilitation and the total rehabilitation time could contribute to improvement, regardless of whether the setting was outpatient or inpatient. In addition, the outpatient rehabilitation study of Schenkman et al.,¹⁴⁾ which involved treadmill walking three times a week for approximately 6 months, demonstrated that high exercise intensity was associated with reduced exacerbation of motor symptoms. In that study, participants were divided into a high-intensity group (targeting 80%–85% of maximum heart rate), a moderate-intensity group (targeting 60%–65% of maximum heart rate), and a control group. A significant difference in motor symptom progression was observed between the high-intensity group and the control group. These findings suggest that exercise intensity may also influence the outcomes of short-term intensive rehabilitation programs. However, in the present study, heart rate was not monitored during exercise sessions, and therefore the intensity of the exercise could not be classified. Future studies may be warranted to incorporate objective indicators such as heart rate to accurately assess exercise intensity and clarify its impact on rehabilitation outcomes.

Although the presence or severity of wearing-off was not directly assessed in individual patients, treatment-related motor complications, including wearing-off and dyskinesia, were evaluated using MDS-UPDRS Part IV (maximum score: 24). The total score showed a slight, non-significant decrease from 4.0 before rehabilitation to 3.0 after rehabilitation (P=0.423). These findings suggest that, if present, such complications were relatively mild and unlikely to have substantially affected motor function outcomes.

Regarding motor ability, no improvement was observed in the 10-m walking speed, 10-m walking steps, muscle mass, or grip strength. However, improvements were noted in the SPPB and the TUG for both the left and right sides, indicating enhanced abilities in standing, sitting, balance, and turning without heavy reliance on muscle strength. For walking speed, some reports have indicated significant improvements in patients with PD through the use of visual and auditory cues as well as treadmill walking.^15,16) Adopting such training methods can potentially lead to improvements in walking speed.

Although cognitive function has been reported to decline in older hospitalized patients,¹⁷⁾ the present study revealed a significant improvement in reality orientation in CogEvo. Unlike the MMSE-J and FAB, CogEvo does not have an upper scoring limit, allowing the modality to detect even subtle changes in neuropsychological functions. The significant improvement in reality orientation in CogEvo may be attributed to several factors: an increase in self-awareness through a focus on their physical abilities during rehabilitation; the establishment of fixed waking, sleeping, and eating times during their hospital stay; and enhanced time-consciousness fostered through daily rehabilitation interventions. However, no improvements were noted in the overall neuropsychological function measures, including the MMSE-J, frontal lobe function assessed by the FAB, and the CogEvo results for memory, executive function, visuospatial cognition, and attention. The lack of improvement in the aforementioned areas may be attributed to ceiling effects in the assessments, rehabilitation program content, or duration-related factors. At the time of admission, the average scores for patients with PD were relatively high: 27.3±2.9 for MMSE-J, 33.8±1.9 for FIM cognitive items, and 14.1±3.0 for FAB, suggesting that ceiling effects may have prevented further improvements from being detected. Regarding the content of the rehabilitation program, the study of Ventura et al.¹⁸⁾ involving ballet- or dance-based group exercises (75 min per session for a total of ten sessions over approximately 4 months) also demonstrated neuropsychological function improvements in patients with PD. Therefore, incorporating complex motor tasks, such as dancing, into short-term intensive rehabilitation may further enhance other neuropsychological functions. Regarding the duration of rehabilitation, Krause et al.²⁾ reported that a short-term intensive outpatient rehabilitation program of 2–3 weeks did not achieve any improvements in the MMSE. However, Baldassarre et al.⁴⁾ observed improvements in the MMSE, FAB, and Montreal Cognitive Assessment in a 6-week inpatient intensive rehabilitation program, which included 60-min sessions of relaxation, stretching exercises, aerobic exercises, and occupational therapy performed thrice daily. These findings suggest that although short-term intensive rehabilitation lasting 2–3 weeks may not lead to overall improvements in cognitive function, a 6-week program may be sufficient to observe such changes.

Our results also confirmed that short-term intensive inpatient rehabilitation improved reality orientation among neuropsychological functions. Improvements in reality orientation, such as time, place, people, and objects, strengthen the memory of events and situations experienced in daily life.¹⁹⁾ Consequently, the improvement of reality orientation is believed to contribute to the enhancement of other cognitive functions, making the improvement of reality orientation by short-term intensive rehabilitation highly significant.

In this study, the intervention was implemented over a period of 2 or 3 weeks, with ten participants completing a 2-week program and five participants completing a 3-week program. This allocation was based on each patient’s individual preferences and clinical circumstances, reflecting a pragmatic approach in a real-world clinical setting. However, given the small number of participants in each group, especially the 3-week group, we did not conduct a statistical comparison of outcomes between the two durations. This represents a limitation of the present study, and future research with a larger sample size is needed to clarify whether the duration of intervention influences rehabilitation outcomes. Moreover, this study did not include follow-up assessments after discharge, and thus the long-term sustainability of the rehabilitation effects remains unclear. In the outpatient rehabilitation study by Schenkman et al.,¹⁴⁾ patients in the control group who did not engage in exercise over a 6-month period showed a significant worsening of motor symptoms compared with those who participated in high-intensity exercise. These findings suggest that although short-term intensive inpatient rehabilitation may yield improvements, symptoms could deteriorate again if exercise is not maintained post-discharge. Conversely, it is possible that continued home-based exercise may help sustain the benefits of the inpatient rehabilitation program over the long term.

This study has several limitations. First, the sample size was relatively small, which may have limited the generalizability of the findings. Second, the participants required minimal assistance, making them likely to respond favorably to rehabilitation interventions. However, this may have introduced selection bias. Third, the evaluation of treatment effects was not blinded. This may have influenced the validity of the results, especially in the MDS-UPDRS Part III, which depends on the evaluator’s judgment. To minimize inter-rater variability, the same evaluator performed both the pre-intervention and post-intervention assessments. Finally, this study lacked a control group, preventing direct comparisons and potential overestimation of the effects of the intervention. This study investigated the effects of a short-term intensive inpatient rehabilitation program in 15 patients with Parkinson’s disease who voluntarily sought and consented to participate in this specific program. Because all participants willingly chose this rehabilitation program, random assignment to a control group (non-intervention or alternative intervention) was ethically and practically challenging. Further studies with larger sample sizes and randomized controlled designs are required to validate our findings.

CONCLUSIONS

Overall, the results demonstrated that even short-term inpatient rehabilitation (2–3 weeks) improved motor and non-motor symptoms, motor abilities, reality orientation, and QOL in patients with PD. Improvements in reality orientation may also enhance other cognitive functions. The results of this study suggest that short-term intensive rehabilitation in patients with PD may achieve worthwhile outcomes, even within a limited timeframe. Further discussion of the appropriate duration of inpatient rehabilitation for patients with PD is warranted.