The frequency of sarcopenia and factors affecting appendicular muscle mass in patients with systemic sclerosis

Aim. To determine the frequency of sarcopenia (SP) and to identify factors associated with the muscle mass in women with systemic sclerosis (SSc).Materials and methods. The study included 64 women with SSc aged 40–70 years. Questionnaires, clinical, instrumental, laboratory examinations and absorptiometry. Linear regression analysis was performed to identify factors associat ed with appendicular muscle mass (AMM).Results. Probable SP was detected in 35 (54.7 %), and confirmed SP – 17 (26.5 %) women with SSc. The frequency of SP did not differ depending on the form of the disease. Univariate linear analysis revealed the relationship between the AMM and BMI, nutritional status; mid-upper arm, waist, hip and calf circumferences, skin Rodnan score, cumulative dose of glucocorticoids (GC) and BMD of the proximal hip. Multivariate linear analysis confirmed the presence of associations between the AMM index and BMI (b = 0.65; p <0.001), the Rodnan skin score (b = –0.19; p = 0.047), the cumulative dose of GC (b = –0.22; p = 0.021).Conclusion. The study demonstrated that more than a quarter of patients with SSc had a confirmed SP. Although age is the main risk factor for SP in the general population, in our study it did not differ between patients with low and normal AMM. The cumulative dose of GC and the Rodnan skin score were negatively, and BMI was positively associated with the value of AMМ.