Background/Purpose: Systemic Sclerosis (SSc) is an autoimmune disease that characterized by endothelial dysfunction, inflammation and fibrosis. It is associated with high mortality and physical impairment. We assessed the prevalence of sarcopenia in SSc patients and correlated sarcopenia with muscle strength and quality of life, also taking other clinical parameters into account.

Methods: Patients meeting the ACR/EULAR 2013 criteria for SSc were included in this study. Body composition was assessed using bioelectrical impedance analysis. Fat free mass (FFM) was estimated using the equation of Kyle and was normalized to patients’ height using the square of body size (FFM/m² = FFMI). Sarcopenia was defined as a FFMI value below 17.4 kg/m² for men and < 15 kg/m² for women. Maximal grip strength was measured using the Jamar Dynamometer, maximal knee extension strength using the Digimax and expiratory peak flow using a peak flow meter. Quality of life was assessed using the SF-36®, while C-reactive protein (CRP), hemoglobin (Hb) and other clinical parameters were quantified by routine laboratory testing or by history taking.

Results: 111 patients were included in this study (101 women and 10 men; age 59.7 ± 13.8 years, BMI 24.5 ± 5 kg/m²). 53 (47.7%) patients were diagnosed with sarcopenia. Patients with sarcopenia differed significantly from patients without sacropenia with respect to maximal grip strength, knee extension strength, peak flow and CRP. They did not differ in age and select clinical parameters such as gastrointestinal involvement, total number of organs involved, number of comorbidities and number of medical therapies. Absolute FFM correlated significantly with maximal grip, knee extension strength and peak flow (r = .64, r = .366 and r = .48, respectively, p < 0.0001). With respect to quality of life there was no significant difference between patients with and those without sarcopenia.

Conclusion: There was a high prevalence of sarcopenia among SSc patients in our study. Sarcopenia was associated with an impairment of muscle strength, low hemoglobin and high inflammatory activity.