Assessment of Factors Related to Sarcopenia in Patients with Systemic Sclerosis

Objectives: Systemic sclerosis (SSc) patients exhibit a heightened vulnerability to sarcopenia, a condition characterized by the loss of muscle mass and strength. This study aims to determine the prevalence of sarcopenia in patients with SSc and to investigate the associated factors contributing to this condition. Methods: Eighty patients with SSc were included in the study, and their demographic and clinical characteristics, body composition by bioelectrical impedance analysis, SARC-F score, chair-stand test performance, and 4 m walking speed were recorded. Results: Among the 80 participants, 91.3% were female, with a median age of 56.5 years (range 45-65). The majority (70%) had limited SSc, and 71.3% reported at least one comorbidity. According to the International Physical Activity Questionnaire, only 12.5% of participants met the criteria for an active lifestyle. The SARC-F questionnaire indicated that 20% of patients were at risk for sarcopenia. The prevalence of sarcopenia among patients showed considerable variability: 5% (95% CI 0.1-9) were identified through the appendicular skeletal muscle index (ASMI), 8.8% (95% CI 2.4-15) via the fat-free mass index (FFMI), and a concerning 20% (95% CI 11-29) according to the skeletal muscle mass index (SSMI). A multivariate logistic regression analysis identified age as the only factor significantly influencing the SARC-F score, with an odds ratio of 1.081 (95% CI 1.012-1.154, p = 0.020). Additionally, the older age group demonstrated a lower level of physical activity, poorer chair-stand test outcome, and slower 4 m gait speeds (p = 0.013, p = 0.008, p = 0.001, respectively), as well as a higher reported frequency of falls (p = 0.039). Conclusions: Sarcopenia is a prevalent issue among individuals with SSc, particularly in the older population. This study did not identify a direct correlation between sarcopenia and SSc subtype, disease activity, or other clinical parameters. However, the need for an improved cut-off value for diagnosing sarcopenia in this specific cohort is evident.