Sarcopenia in systemic sclerosis-associated interstitial lung disease

Systemic sclerosis-associated interstitial lung disease (SSc-ILD) is a significant complication that impairs lung function and increases morbidity. Sarcopenia, characterized by the loss of muscle mass and function, is commonly found in chronic diseases such as systemic sclerosis. This study aimed to evaluate the prevalence of sarcopenia in patients with SSc-ILD and investigate its cross-sectional associations with pulmonary function test parameters, estimated pulmonary artery pressure and quantitative radiological lung involvement. In this cross-sectional study conducted between 2024 and 2025, 40 patients with systemic sclerosis (2013 ACR/EULAR criteria) and high-resolution computed tomography-confirmed interstitial lung disease were evaluated. Patients with overlap myositis, acute infections, severe orthopedic/neurological limitations, and end-stage organ failure were excluded. Sarcopenia was diagnosed based on European Working Group on Sarcopenia in Older People 2 criteria using muscle mass (bioelectrical impedance analysis) and handgrip strength measurements. Pulmonary function tests (FVC, single-breath transfer factor of lung for carbon monoxide), echocardiographic sPAP estimations, and quantitative high-resolution computed tomography lung density analysis were performed. These findings highlight the potential impact of sarcopenia on lung function and the association of sarcopenia with radiological findings in SSc-ILD SSc-ILD. Among the 40 analyzed patients (mean age: 55.8 ± 10.8 years, 85.0% female, mean BMI: 28.7 ± 5.0 kg/m2), sarcopenia was identified in 10 patients (25.0%). Patients with and without sarcopenia were compared to analyze its effects on pulmonary function and radiological findings. Patients with sarcopenia had significantly lower lung diffusion capacity (transfer factor of lung for carbon monoxide) and forced vital capacity % values and significantly higher radiological lung involvement compared to those without sarcopenia (P = .004, P = .023, and P = .035, respectively). Systolic pulmonary artery pressure was also significantly higher in sarcopenic patients (P = .031). Additionally, fat-free mass index, fat-free mass, muscle mass, and handgrip strength were significantly lower in sarcopenic patients (P < .001).