Prevalence and Associated Factors of Sarcopenia in Stroke Patients: A Cross-Sectional Observational Study
Conditions: Sarcopenia, Cerebral Stroke, Cerebral Vascular Accident (CVA)/Stroke
Sponsor: Cishan Hospital, Ministry of Health and Welfare

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Study Protocol with Statistical 
Analysis Plan (SAP)  
Official Title: Prevalence and Associated Factors of Sarcopenia in Stroke 
Patients: A Cross-Sectional Observational Study 
Document Type: Study Protocol with SAP and ICF 
NCT number: NCT07492849 
IRB approved number: A-ER-114-059 (by IRB, National Cheng Kung 
University Hospital, Tainan, Taiwan) 
Document Date: March 20, 2026 
Sponsor / Responsible Organization: Cishan Hospital, Ministry of Health and 
Welfare, Taiwan 
Principal Investigator: Sheng-Hui Tuan, MD, PhD 
Department of Physical Medicine and Rehabilitation 
Cishan Hospital, Ministry of Health and Welfare, Taiwan 
Brief Description of Document: This document provides the full study protocol 
and statistical analysis plan for a cross-sectional observational study 
investigating the prevalence and associated factors of sarcopenia in post-acute 
and chronic stroke patients. The study includes comprehensive assessments of 
muscle mass, muscle strength, physical performance, nutritional status, and 
quality of life, and aims to compare sarcopenia-related characteristics across 
different stroke stages, age groups, and sexes. 
 

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A. BACKGROUND 
Sarcopenia is a progressive and generalized skeletal muscle disorder characterized by the 
accelerated loss of muscle mass, strength, and physical performance. It has been recognized 
as a major public health concern in aging societies, with a prevalence exceeding 20% among 
individuals aged 65 years and older in Taiwan. Sarcopenia is strongly associated with adverse 
clinical outcomes, including increased risks of falls, frailty, hospitalization, disability, and 
mortality. 
Stroke is a leading cause of long-term disability worldwide. Advances in acute stroke 
management have significantly improved survival rates; however, a growing population of 
stroke survivors now faces long-term complications. Among these, sarcopenia has emerged as 
a critical but often underrecognized condition. Stroke-related sarcopenia may result from 
multiple mechanisms, including immobilization, denervation, systemic inflammation, 
malnutrition, and reduced physical activity. 
Previous studies have evaluated sarcopenia-related indicators in stroke populations, such as 
handgrip strength, calf circumference, or walking speed. However, most studies have relied 
on single-domain measurements and have not provided a comprehensive assessment 
integrating muscle mass, muscle strength, imaging-based muscle quality, and functional 
performance. Furthermore, comparisons between different stages of stroke recovery—
particularly between post-acute care (PAC) and chronic stroke patients—remain limited. 
Given that muscle decline may begin as early as 40 years of age and may vary by sex and 
disease severity, a multidimensional assessment across different subgroups is warranted. 
Therefore, this study aims to comprehensively evaluate sarcopenia-related variables in stroke 
patients using multiple clinical tools and to explore associated factors across different clinical 
conditions. 
B. OBJECTIVES 
The primary objective of this study is to comprehensively analyze sarcopenia-related 
variables in stroke patients using multiple clinical assessment tools, including body 
composition, muscle strength, imaging, and functional performance. 

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Specifically, this study aims to compare sarcopenia-related indicators between post-acute 
care (PAC) stroke patients and chronic stroke patients, and to evaluate differences across age 
groups (40–65 years versus >65 years), sex, and stroke severity. 
The secondary objective is to determine the prevalence of sarcopenia in these populations 
and to identify potential factors associated with sarcopenia in stroke patients. 
C. Study Design 
This study is designed as a cross-sectional observational study conducted at Cishan 
Hospital, Ministry of Health and Welfare, Taiwan. 
Participants are classified into two cohorts based on stroke stage. The first cohort includes 
chronic stroke patients whose stroke onset occurred more than six months prior to enrollment. 
The second cohort includes post-acute care (PAC) stroke patients who are at least 14 days 
post-stroke, have been assessed by a neurologist as eligible for PAC transfer, and are admitted 
to a PAC ward. 
A case-control observational model is adopted to compare the characteristics between these 
two cohorts. The study follows a cross-sectional time perspective, with all data collected at a 
single time point. 
D. Participants 
The study population consists of adult patients aged 40 years or older who have been 
diagnosed with stroke by a qualified specialist and have corresponding ICD-10 diagnostic 
codes documented in the electronic medical record system of Cishan Hospital. Both ischemic 
and hemorrhagic stroke patients are eligible for inclusion. 
Participants must have sufficient cognitive and physical function to complete sarcopenia-
related assessments, including muscle strength testing, walking speed measurement, and 
questionnaire-based evaluations, as judged by the principal investigator. 
Participants are recruited using a non-probability sampling method. A total of 
approximately 80 participants are expected to be enrolled, with a planned allocation ratio of 
1:1 between chronic stroke patients and PAC stroke patients. 

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E. Study Procedures 
All participants undergo a standardized assessment at a single time point upon enrollment. 
The assessment protocol includes both objective and subjective measurements. Objective 
assessments encompass body composition analysis using bioelectrical impedance analysis 
(BIA), measurement of quadriceps muscle strength using a handheld dynamometer, 
ultrasound-based assessment of muscle thickness of the quadriceps and gastrocnemius 
muscles, calf circumference measurement, dominant handgrip strength testing, walking speed 
evaluation, and sarcopenia screening using the SARC-F questionnaire and the Mini 
Nutritional Assessment (MNA). 
Subjective assessment includes evaluation of health-related quality of life using the EQ-5D 
questionnaire. 
All measurements are conducted by trained healthcare professionals using standardized 
procedures to ensure reliability and reproducibility. To minimize measurement bias, 
consistent protocols and equipment settings are applied across all participants. 
F. Outcome Measures 
Primary outcome measures include appendicular skeletal muscle mass index (ASMI), 
dominant handgrip strength, and gait speed, which are key diagnostic components of 
sarcopenia according to established consensus criteria. 
Secondary outcome measures include quadriceps muscle strength measured by maximal 
voluntary isometric contraction (MVIC), ultrasound-measured muscle thickness of the 
quadriceps and gastrocnemius muscles, calf circumference, SARC-F score, Mini Nutritional 
Assessment (MNA) score, and EQ-5D health-related quality of life score. 
All outcome variables are measured at enrollment and analyzed as continuous or 
categorical variables as appropriate. 
G. Statistical Analysis Plan 
All statistical analyses are performed using SPSS software (version 19.0 or later; IBM Corp., 
Armonk, NY, USA). 

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Descriptive statistics are used to summarize baseline characteristics. Continuous variables 
are presented as mean ± standard deviation (mean ± SD), while categorical variables are 
expressed as frequencies and percentages. 
The normality of continuous variables is assessed using appropriate tests such as the 
Shapiro–Wilk test. 
For comparisons between two groups (e.g., PAC vs. chronic stroke, younger vs. older age 
groups), independent sample t-tests are used for normally distributed variables. For non-
normally distributed data, the Mann–Whitney U test is applied. 
Categorical variables, including sarcopenia classification categories, are analyzed using the 
chi-square test or Fisher’s exact test as appropriate. 
If applicable, multivariate analyses (e.g., logistic regression) may be conducted to identify 
independent factors associated with sarcopenia. 
A two-tailed p-value of less than 0.05 is considered statistically significant.