Cause of Mortality and Sarcopenia in Patients with Idiopathic Pulmonary Fibrosis Receiving Anti-Fibrotic Therapy

Summary at GlanceSkeletal muscle wasting (sarcopenia) without obvious weight loss is commonly found in patients with IPF receiving antifibrotic therapy. Most study patients died of chronic respiratory failure and skeletal muscle loss was associated with worse outcomes in antifibrotic therapy, suggesting that sarcopenia prevention is crucial for patients with IPF.
Background and objective: Recent research has highlighted the fundamental role of sarcopenia, characterized by loss of skeletal muscle mass and strength, with a risk of poor outcomes. Anti-Fibrotic Therapy (AFT) preserves lung function by preventing the annual decline in forced vital capacity (FVC) and is associated with improved outcomes in patients with idiopathic pulmonary fibrosis (IPF). However, altered cause of death and prognostic implications of sarcopenia in patients with IPF receiving AFT remain unknown.Methods: This study comprised two cohorts of patients with IPF receiving AFT, historical cohort of IPF patients without AFT and controls. The cause of mortality was compared with a historical cohort. Sarcopenia was assessed by measuring the cross-sectional area (ESMCSA) and muscle-attenuation (ESMMA) of erector spinae muscles via computed-tomography.Results: Patients with IPF had smaller ESMCSA and lower ESMMA but similar body mass index (BMI) than controls, suggesting patients with IPF had skeletal muscle loss without any obvious body weight loss. The most common cause of mortality in patients receiving AFT was chronic respiratory failure, accounting for approximately 60%, and decreased proportions of lung cancer were found. Subsequently, low ESMCSA was an independent prognostic factor associated with worse survival rates. Furthermore, combined assessment of ESMCSA, %FVC-predicted, and BMI values provided clear prognostic distinction.Conclusion: Patients with IPF receiving AFT showed skeletal muscle loss without obvious weight loss. These patients mostly died by chronic respiratory failure, and skeletal muscle wasting has prognostic significance, suggesting that preventing sarcopenia as well as preserving lung function is important for managing these patients.
雑誌掲載タイトル：Cause of mortality and sarcopenia in patients with idiopathic pulmonary fibrosis receiving antifibrotic therapy