457

ORIGINAL
The association between sarcopenia and functional outcomesin patients undergoing convalescent rehabilitation
Yuki Yamasaki1, Yui Honda2, Mami Inoue-Umezaki2, Ryoko Makieda2, Yoko Endo1, 2, Kozo Hanayama3, Hiroshi Sakaue4,
and Fusako Teramoto1
Department of Clinical Nutrition, Faculty of Health Science and Technology, Kawasaki University of Medical Welfare, Okayama, Japan,
Department of Nutrition, Kawasaki Medical School Hospital, Okayama, Japan, 3Department of Rehabilitation Medicine, Kawasaki Medical
School, Okayama, Japan, 4Department of Nutrition and Metabolism, Institute of Biomedical Sciences, Tokushima University Graduate School,
Tokushima, Japan
1

2

Abstract : Sarcopenia is widely believed to be linked to poorer outcomes in inpatient rehabilitation. This study
aimed to assess the impact of sarcopenia on functional outcomes and dietary intake during hospitalization in
adults undergoing convalescent rehabilitation. We conducted a retrospective cohort analysis at a single rehabilitation institution. The Asian Working Group Consensus Criteria for Sarcopenia was used to diagnose. The
Functional Independence Measure (FIM) score was used at hospital discharge to measure the primary functional
outcome. Energy and protein intakes during hospitalization were calculated as part of the nutritional assessment. There were 126 patients in the research (median age, 73 yr ; 54% women). Stroke (n = 73 ; 53.4% sarcopenia)
and musculoskeletal disorders (n = 53 ; 56.6% sarcopenia) were among the admission diagnoses. Multiple linear
regression analysis revealed that the FIM total score at discharge was modestly associated with sarcopenia onlyin stroke patients (β = −0.1872, P = 0.09), as well as significantly and independently associated with protein intake during admission only in stroke patients (β = 0.3217, P < 0.05). In hospitalized stroke patients undergoingconvalescent therapy, sarcopenia is related to lower functional results. Early identification of sarcopenia andtreatment with rehabilitation nutrition should be implemented in this population. J. Med. Invest. 70 : 457-463,
August, 2023
Keywords : Sarcopenia, Convalescent rehabilitation, Functional outcomes, Functional Independence Measure (FIM), Nutrition

INTRODUCTION
Sarcopenia is defined as the loss of skeletal muscle mass andstrength with aging (1). In frail older persons, maintaining or
enhancing physical function and independent functioning is
crucial (2), and sarcopenia adds to physical frailty (3). It causes
more falls, functional dependency, and death (4). Sarcopenia has
primarily been studied in community-dwelling adults and nursing home residents, and it is a major risk factor for mobility impairment, falls, disability, loss of independence, hospitalization,
institutionalization, and death (5-8). The prevalence of sarcopenia in hospital-based rehabilitation settings is approximately
50% (9, 10). Although it is often assumed that sarcopenia isassociated with poorer outcomes in hospital-based rehabilitation
settings (11), few studies have established a connection between
sarcopenia and functional outcomes in hospitalized older adults
receiving rehabilitation.
Sarcopenia, a skeletal muscle ailment, is caused by aging,inadequate nutritional intake, disease, and inactivity, which
results in a considerable loss of cell mass, particularly in skeletal
muscle (12, 13). It is not enough to maintain these patients’ nutritional condition ; a significant amount of energy is necessary
to rebuild their lean mass and skeletal muscle mass. The clinicalnutrition community has long acknowledged the importanceof modifying energy requirements in these situations (14, 15).
Received for publication June 13, 2023 ; accepted July 13, 2023.
Address correspondence and reprint requests to Yuki Yamasaki,
Faculty of Health Science and Technology, Department of Clinical Nutrition, Kawasaki University of Medical Welfare, 288, Matsushima,
Kurashiki, Okayama 701-0193, Japan and Fax : +81-86-464-1109.

However, there is no clear idea of nutritional intervention to address these circumstances in sarcopenic patients. Furthermore,malnutrition is widely recognized in recovery and rehabilitation
units (16), and because improved nutritional status and weightgain are associated with improved activities of daily living(ADLs) (17-19), developing a nutritional management strategy
to improve nutritional status in clinical settings is important.
As a result, we conducted a retrospective cohort study of inpatient adults undergoing convalescent therapy to see how sarcopenia affected functional outcomes, such as ADLs, home discharge
rates, and nutritional intake during hospitalization.

MATERIALS AND METHODS
Participants and setting

From April 2019 to March 2022, we conducted a single-center,retrospective, cross-sectional study. We considered all consecutive patients hospitalized in Kawasaki Medical School Hospital’s
convalescent rehabilitation unit. The convalescent rehabilitation
ward is unique in the Japanese healthcare system, serving patients who require rehabilitation after being discharged from anacute care unit. The study included patients newly admitted to
the ward. Exclusion criteria included refusal to consent, missing
data, altered consciousness, edema, and altered hydration status, pacemaker implantation, parenteral nutrition, or diseases
other than the two main diseases (stroke and musculoskeletal
diseases). The observation period lasted from the time of admission to the time of discharge from the hospital.

Data collection
At admission, basic information, such as age, gender,

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Y. Yamasaki, et al. Sarcopenia effect on convalescent rehabilitation outcomes

admission diagnosis, body mass index (BMI), admission diagnosis, number of medications prescribed at admission (20), including antihypertensives and antipsychotics, time (days) since theonset of the primary illness, and some laboratory tests (serum
albumin, hemoglobin, and C-reactive protein) were collected.
BMI, bioelectrical impedance analysis (BIA) for skeletal muscle
mass and fat mass, handgrip strength (HGS) and calf circumference (CC), and Functional Independence Measure (FIM) scoresfor physical and cognitive function were tested within 7 daysof admission (21). HGS was measured using a Smedley hand
dynamometer (TTM, Tokyo, Japan) with the patient standing or
sitting, depending on ability, with arms straight at the side ; anaverage of two readings was taken. BIA was assessed under
the following conditions : adequate hydration, 2 h after the lastmeal, bed rest for 20 min before the evaluation, and no current
diagnosis of fever, tremor, or poor physical condition. The device
used (InBody S10, InBody, Tokyo, Japan) was the latest version
of a validated BIA device, and its measurement is consideredminimally affected by fluid overload when estimating muscle
mass (22).

Main outcomes
The primary outcome was the FIM score at the time of discharge from the convalescent rehabilitation center (21). The FIM
is split into two domains : motor domain (FIM motor) with 13
sub-items and cognitive domain (FIM cognitive) with five subitems. Tasks are graded on a 7-point ordinal scale ranging fromcomplete help to complete independence. The FIM total scoreis between 18 and 126 points, the FIM motor score is between
13 and 91 points, and the FIM cognitive score is 5 to 35 points.
Lower scores imply dependency.
BMI, skeletal muscle mass index (SMI), HGS, and CC at
the time of discharge from the convalescent rehabilitation unit,
length of stay (LOS), and discharge rate to home are secondary
outcomes.

Diagnosis of sarcopenia
Sarcopenia was diagnosed based on the Asian Working Groupfor Sarcopenia 2019 consensus when both low muscle strength,
as measured by grip strength, and low SMI, as measured by
BIA, were present (23). Grip strength cutoff values were lessthan 28 kg for males and 18 kg for women, and SMI cutoff values
were fewer than 7.0 kg / m2 for men and 5.7 kg / m2 for women.

Nutrition assessment
Energy and protein intake was assessed as the average during
the entire hospitalization. Dietary intake at the time of admission was provide at 30 kcal per ideal body weight for energy and1.2 g per ideal body weight for protein.
A nurse estimated the energy and protein intakes and visually checked the intake ratio to the amount given to the patient.
Breakfast, lunch, and dinner intakes were recorded, and basedon oral intake, average daily energy and protein intakes for theentire hospitalization period were calculated and divided by thedesired weight at admission to estimate energy and protein intakes per ideal body weight. A BMI of 22.0 kg / m2 was the ideal
body weight (24).

Statistical analysis
For parametric data, values are provided as mean (SD) or
as median (interquartile range [IQR]) and number (%) for
nonparametric and categorical data, respectively. The t test,
Mann–Whitney U test, and χ2 test were used to compare thosewith and without sarcopenia according to disease. Multiple linear regression analyses were performed to assess if sarcopenia
or energy and protein consumption at hospital admission wereindependently related to FIM total at hospital release. The variance inflation factor (VIF) was used to quantify multicollinearity : a VIF between 5 and 10 was deemed to reflect the absenceof multicollinearity. P < 0.05 was considered statistically significant. JMP software (SAS Institute Inc., Tokyo, Japan) was used
for all statistical analyses.

EthicsAll participants or their legal guardians provided informed
consent. The study was approved by the Institutional Review
Board of Kawasaki Medical School Hospital (Okayama, Japan),where the study was conducted. This study was conducted inaccordance with the tenets of the Declaration of Helsinki.

RESULTS

Patient characteristics and comparison based on the presence ofsarcopenia
During the study period, 349 patients were newly admitted,
met the inclusion criteria, and were further assessed for eligibility. Patients with missing data, altered consciousness, pacemaker
implantation, and other than the two main diseases were excluded from the analysis. Finally, 126 participants were included in
the study.
Table 1 shows the clinical and demographic data of the patients. The median age of the patients was 73 (IQR : 61–81)
years, and 46.0% were male. The median FIM total, FIM
motor, and FIM cognitive scores were 96 (IQR : 69–108), 66(IQR : 44–75), and 34 (IQR : 27–35), indicating that a significant
proportion of patients were physically at baseline. Stroke (n =73 ; 57.9%) and musculoskeletal diseases (n = 53 ; 42.1%) werethe most frequent medical problems. Sarcopenia was found in
53.4% (n = 39) of stroke patients and 56.6% (n = 30) of musculoskeletal patients. Patients with sarcopenia who had a stroke
were substantially older (P < 0.05). They had lower BMI, SMI,
and CC than people who did not have sarcopenia (all, P < 0.01).
According to comorbidities, there were no variations in FIM
score between individuals with and without sarcopenia. Patientswith stroke who had sarcopenia had substantially longer days
from onset than those who did not have sarcopenia (P < 0.05).
According to significant comorbidities, indicators of nutritional
status, such as albumin and hemoglobin, and markers of inflammation, such as C-reactive protein (CRP), showed no variations
between patients with and without sarcopenia.

Clinical and functional outcomes at hospital discharge between
patients with and without sarcopenia according to diseases
The results of the univariate analysis for clinical and functional outcomes at hospital discharge between patients with andwithout sarcopenia according to the main diseases are shown in
Table 2. Patients with sarcopenia had substantially lower BMI,
SMI, and CC than those without (all, P < 0.01). FIM total and
FIM motor were significantly lower in patients with sarcopenia
following stroke than in those without (all, P < 0.01 or P < 0.05).
After the stroke, FIM cognitive function was slightly lower inpatients with sarcopenia than those without (P = 0.0699). According to musculoskeletal illnesses, the FIM score revealed nodifferences between patients with and without sarcopenia. According to significant comorbidities, there were no differences in
LOS between patients with and without sarcopenia. According
to stroke, home discharge rate was marginally worse in patientswith sarcopenia than those without (P = 0.0571). According tomusculoskeletal illnesses, home discharge rate revealed no differences between patients with and without sarcopenia.

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The Journal of Medical Investigation Vol. 70 August 2023
Table 1. Baseline characteristics of patients and between-group comparison according to the presence of sarcopenia
Stroke (n = 73)
Total(N = 126)

Sarcopenia(n = 39)

No sarcopenia(n = 34)

73 (61–81)

76 (69–83)

65 (53–73)

Musculoskeletal disease (n = 53)
P value

Sarcopenia(n = 30)

No sarcopenia(n = 23)

P value

0.002479 (70–82)

76 (58–80)

0.1406

Demographic
Age (yr), median (IQR)
Sex, n (%)

0.63560.0786Male

58 (46.0)

21 (53.8)

21 (61.8)

6 (20.0)

10 (43.5)

Female68 (54.0)

18 (46.2)

13 (38.2)

24 (80.0)

13 (56.5)

33 (26.2)

17 (43.6)

16 (47.1)

Reason for admission, n (%)
StrokeBrain infarction
Cervical spondylotic myelopathy

9 (7.1)7 (17.9)2 (5.9)Brain hemorrhage

8 (6.3)2 (5.1)6 (17.6)

Subarachnoid hemorrhage

6 (4.8)4 (10.3)

2 (5.9)Spinal cord injury

6 (4.8)2 (5.1)4 (11.8)

Brain tumor

4 (3.2)4 (10.3)

Peripheral neuropathic

1 (0.8)1 (2.6)Polyneuropathy

1 (0.8)1 (2.6)

Spinal cord tumor

1 (0.8)1 (2.6)

Multiple sclerosis

1 (0.8)1 (2.9)Cerebral palsy

1 (0.8)1 (2.9)Brain arteriovenous malformation

1 (0.8)1 (2.9)Lateral medullar

1 (0.8)1 (2.9)Musculoskeletal disease
Fractures

33 (26.2)

18 (60.0)

15 (65.2)

Degenerative joint disease

10 (7.9)

6 (20.0)

4 (17.4)

Total knee arthroplasty

7 (5.6)6 (20.0)

Amputation

3 (2.4)1 (4.3)3 (13.0)

Anthropometrics
BMI (kg / m2), median (IQR)

22.3 (24.7–20.2)

20.4 (18.7–22.4)

24.2 (22.0–26.9)<0.0001

21.7 (19.3–22.6)

24.4 (22.7–25.4)

0.0004

SMI (kg / m ), median (IQR)

6.2 (5.3–7.1)

5.5 (4.6–6.5)

7.2 (6.3–7.6)<0.0001

5.4 (4.9–5.6)

7.4 (6.5–8.0)< 0.0001

CC (cm), mean (SD)

32.2 (3.6)

29.9 (2.9)

34.7 (2.8)

0.000130.7 (2.4)

34.4 (3.4)< 0.0001

Handgrip strength (kg), mean (SD)20.1 (9.1)

18.4 (8.6)

23.2 (9.1)

0.053216.8 (6.5)

22.0 (10.8)

0.0666Total

96 (69–108)

86 (52–101)

95 (81–102)

0.2592101 (89–109)

107 (87–112)

0.3643

Motor

66 (44–75)

63 (20–71)

62 (46–74)

0.465367 (54–74)

73 (52–77)

0.4562

Cognitive

34 (27–35)

30 (18–35)

33 (25–35)

0.167035 (32–35)

35 (33–35)

0.5228Days from onset (days), median (IQR)

23 (17–34)

27 (19–40)

21 (14–32)

0.024023 (18–36)

20 (14–28)

0.11802

FIM score, median (IQR)

Drugs
Total (n), median (IQR)

6 (3–7)

5 (3–7)

5 (4–7)0.14415 (2–10)

4 (3–8)0.4562

Antihypertensive drugs, n (%)

57 (45.2)

22 (56.4)

25 (73.5)

0.14834 (13.3)

6 (26.1)

0.2995

Antipsychotics, n (%)

30 (23.8)

9 (23.1)

8 (23.5)

0.9636

10 (33.3)

3 (13.0)

0.06663.6 (0.5)

3.4 (0.4)

3.8 (0.5)

0.97453.5 (0.5)

3.5 (0.5)

0.9743

Laboratory data
Albumin (g / dL), mean (SD)
Hemoglobin (g / dL), mean (SD)11.9 (1.9)

12.0 (1.8)

13.2 (1.9)

0.163910.8 (1.6)

11.4 (1.7)

0.1639

CRP (mg / dL), median (IQR)

0.24 (0.09–0.55)

0.14 (0.05–0.38)

0.23 (0.08–0.40)

0.62390.36 (0.14–0.64)

0.37 (0.14–1.01)

0.8393Note. Data are presented as mean or median. Between-group comparisons were made using the t test and Mann–Whitney U test.
Abbreviations : BMI, body mass index ; CC, calf circumference ; CRP, C-reactive protein ; FIM, Functional Independence Measure ; IQR,
interquartile rate ; SMI, skeletal muscle mass index.

Y. Yamasaki, et al. Sarcopenia effect on convalescent rehabilitation outcomes

460

Energy and protein intake and dietary assessment in admission
between patients with and without sarcopenia by disease

with and without sarcopenia.

Table 3 compares the dietary assessments of patients withand without sarcopenia admission based on the major disorders.
According to the primary diseases, there were no changes in energy and protein intake and dietary intake rate between patients

Multiple linear regression analysis for FIM total at hospital discharge
according to diseases
Table 4 shows the multivariate analyses for FIM total at
hospital discharge after adjusting for sarcopenia or energy andTable 2. Univariate analysis for clinical and functional outcomes at hospital discharge between patients with and without sarcopenia according to the diseases

Stroke (n = 73)
Sarcopenia(n = 39)

No sarcopenia(n = 34)

20.1 (18.8–20.5)

24.5 (21.9–26.0)

Musculoskeletal disease (n = 53)
P value

Sarcopenia(n = 30)

No sarcopenia(n = 23)

P value< 0.0001

21.4 (18.9–22.7)

23.6 (22.0–25.5)

0.0006

Anthropometrics
Body mass index (kg / m2), median (IQR)
SMI (kg / m ), median (IQR)

5.7 (5.1–6.5)

7.1 (6.3–7.8)

0.00015.4 (5.1–6.0)

7.3 (6.4–7.8)< 0.0001

31.0 (28.6–32.9)

35.4 (33.6–37.7)< 0.0001

31.6 (30.1–33.2)

33.8 (32.4–36.2)

0.000418.0 (9.3)

23.7 (8.7)

0.098

16.0 (5.9)

20.3 (10.7)

0.0980Total

102 (89–118)

118 (103–122)

0.0178115 (108–118)

115 (113–120)

0.4275Motor

80 (60–85)

86 (72–89)

0.039980 (74–83)

80 (79–85)

0.4060Cognitive

31 (21–35)

34 (30–35)

0.069935 (33–35)

35 (35–35)

0.1221

LOS (days), median (IQR)

59 (32–113)

54 (42–86)

0.580257 (42–76)

58 (35–96)

0.3413Home discharge, n (%)

33 (84.6)

33 (97.1)

0.057127 (90.0)

20 (87.0)

0.72992

Calf circumference (cm), median (IQR)
Handgrip strength (kg), mean (SD)FIM score, median (IQR)

Note. Data are presented as mean or median. Between-group comparisons were made using the t test and Mann–Whitney U test.
Abbreviations : FIM, Functional Independence Measure ; IQR, interquartile rate ; LOS, length of stay ; SMI, skeletal muscle mass index.

Table 3. Energy and protein intake and dietary intake rate in admission between patients with and without sarcopenia according to the diseases
Stroke (n = 73)

Musculoskeletal disease (n = 53)

Sarcopenia(n = 39)

No sarcopenia(n = 34)

P value

Sarcopenia(n = 30)

No sarcopenia(n = 23)

P value

Energy intake in admission (kcal / day / kg IBW),
median (IQR)

26 (24–29)

27 (25–30)

0.617327 (24–32)

30 (26–34)

0.2391

Protein intake in admission (g / day / kg IBW),
median (IQR)

1.1 (0.9–1.2)

1.0 (1.0–1.1)

0.3725

1.1 (0.9–1.2)

1.1 (1.0–1.3)

0.2541

Dietary intake rate in admission (%), median (IQR)

89 (83–93)

92 (86–96)

0.137890 (84–94)

93 (88–96)

0.0712

Dietary assessment

Note. Data are presented as mean or median. Between-group comparisons were made using the t test and Mann–Whitney U test.
Abbreviation : IQR, interquartile rate.

Table 4. Multiple linear regression analysis for FIM total at hospital discharge according to diseases
Stroke (n = 73)

Musculoskeletal disease (n = 53)βP valueβ

P valueAge− 0.4941< 0.0001− 0.1191

0.4263Sex− 0.1851

0.0896− 0.1328

0.3943

Sarcopenia− 0.1872

0.0856− 0.0973

0.5285

Energy intake in admission− 0.2363

0.12410.00220.9919Protein intake in admission

0.3217

0.0365− 0.0099

0.9648R

0.31920.0575

P value< 0.0001

0.72882Note. β , standardized partial regression coefficient. Adjusted for age and sex at admission.

The Journal of Medical Investigation Vol. 70 August 2023
protein consumption on admission by disease. After controlling
for relevant confounders, such as age and gender, sarcopenia wasmodestly linked with FIM total at hospital release according
to stroke (β = −0.1872, P = 0.0856). Furthermore, protein consumption at admission was linked with FIM total after hospital
release on stroke (β = 0.3217, P < 0.05).

DISCUSSION
Sarcopenia, or the age-related loss of muscle mass andstrength, dramatically hinders physical function and independent functioning in frail older persons, increasing the risk offalls, functional reliance, and death. In this cohort study, weinvestigated the impact of sarcopenia on functional outcomes,
such as ADLs, and the rate of release to home among hospitalized people receiving convalescent therapy. There was nodifference in admission FIM ratings between patients with andwithout sarcopenia for stroke. FIM ratings upon discharge werelower in patients with sarcopenia at the time of transfer thanin patients without sarcopenia. Furthermore, sarcopenia waslinked to ADL at discharge in people hospitalized for stroke.
With a β of −0.1872 (stroke), the degree of association was mild
to moderate. It is hypothesized that because stroke significantly
impacts physical functioning, disability, and recovery, the impactof sarcopenia is reduced. This finding is consistent with theresults of Yoshimura et al. survey (25). It has been observed thatmalnutrition and sarcopenia are related to poorer outcomes,
such as ADL and home discharge rates in rehabilitation individuals (25, 26). Our discovery that poststroke sarcopenia isrelated to status after discharge emphasizes the necessity in hospitalized patients. We conducted further analyses to explore therelationship between the presence of sarcopenia and recoveryof physical function. Specifically, we examined the difference in
FIM scores from admission to discharge (FIM gain) in relation
to sarcopenia. However, our results did not show a significant
relationship (data not shown). It is worth noting that FIM gain isoften difficult to improve in patients requiring total assistance,
while a ceiling effect is observed in patients with light assistance, resulting in minimal gains. Conversely, patients withmoderate assistance showed greater gains (27). In addition, thelack of improvement and ceiling effects observed in critically illpatients may influence FIM gains on admission (27). A plausible
explanation for the lack of association between FIM gain and thepresence of sarcopenia in our study could be due to the substantial interindividual variability in admission FIM scores, whichconsequently led to substantial interindividual variability in
FIM gain. To obtain more precise results, future studies should
consider increasing the sample size and performing a more comprehensive examination.
Based on the current findings, there is an urgent need todetect early (i.e., at hospital admission) to commence preventive
and particular interventions to avoid worse functional outcomesamong hospitalized individuals receiving rehabilitation. Resistance training and proper calorie and protein consumption
should be the primary aims of sarcopenia treatment to preserve
skeletal muscle mass and function and restore physical function(28). Protein consumption at admission was linked to FIM scoreat discharge in hospitalized stroke patients undertaking convalescent therapy in this research. In stroke patients, this risk was
relatively low (β of 0.3217). In contrast, in hospitalized stroke
patients receiving convalescent rehabilitation, energy intake atadmission was not related to the FIM score at discharge. Thesefindings imply that dietary protein intake regulation is more important than energy consumption functional outcomes in stroke
patients. Protein intake of 1.0–1.5 g / kg of ideal body weight per

461

day is indicated to improve sarcopenia (29). Protein consumption
in stroke patients with sarcopenia was within the recommended
range in this study. As a result of these findings, it is proposedthat the target protein consumption be increased compared with
the intake in this study to improve functional outcomes in stroke
patients with sarcopenia. Nutritional therapy that accounts fordaily energy consumption, protein requirements, and accumulation is required and will be a future challenge in this study (30).
Previous research has linked sarcopenia in patients withmusculoskeletal disorders to poor functional outcomes due to impaired ADL (25, 31). Our study, however, found no link between
sarcopenia at admission and functional outcomes, including
ADLs, in patients with musculoskeletal disorders. This study’s
sub-analysis could not explain the reasons for the disparity withearlier investigations. Musculoskeletal disease is more likely tocause localized damage than cerebrovascular disease, and thedisease’s severity may be less severe. As a result, the recovery
rate in functional prognosis with or without sarcopenia may differ. This study did not consider factors influencing sarcopenia on
admissions and functional outcomes, such as rehabilitation duration, content, and physical activity levels, which may influence
the association. Similarly, factors influencing these outcomes,
such as family presence, long-term care insurance, living environment, disease severity, and treatment, were not investigated(32-34). Because the investigation was conducted retrospectively,certain unadjusted factors may have influenced the findings.
High-quality prospective studies are needed to study the impactof sarcopenia and functional outcomes on hospital LOS anddischarge rates to home, as well as social contexts, such as thepresence of family members for support and social services.
This study has several limitations. First, the small sample
size and single-study setting may reduce the precision of thestatistical analysis and limit the generalizability of the results.
Future research is needed to see if similar outcomes may beobtained in diverse therapeutic contexts. Second, the effects ofvarious sarcopenia therapies, such as rehabilitation therapy
and nutrition therapy, were not studied. Third, because thestudy was conducted retrospectively, the effect of confounding
factors on the results could not be adequately corrected. Finally,
there was no evidence of a causal association between diet andimproved functional outcomes at hospital discharge in this trial.
The clinical effects of a rehabilitation nutrition on sarcopenia
and functional results in hospital-based rehabilitation settings
should be investigated in future studies.

CONCLUSION
In conclusion, the results suggest that sarcopenia is associatedwith functional status at hospital discharge, emphasizing theimportance of early detection and diagnosis of sarcopenia anddietary management (particularly protein intake) in patients
undergoing convalescent rehabilitation, particularly those withstroke.

CONFLICT OF INTEREST
The authors declared no conflict of interest.

ACKNOWLEDGMENTS
We thank the paramedical staff from the Convalescent Rehabilitation Department Ward of Kawasaki Medical School Hospital for their help with performing patient assessments.

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