Clinical characteristics and mortality risk of sarcopenia in interstitial lung disease: a systematic review and meta-analysis

ObjectiveSarcopenia, prevalent in interstitial lung disease (ILD), increases the risk of poor outcomes. This study aimed to define the clinical characteristics of ILD patients with sarcopenia (ILD-S) and quantify sarcopenia's impact on mortality.MethodsWe systematically searched PubMed, Embase, Cochrane Library, Web of Science, and Scopus for English studies up to 1 September 2026 reporting clinical variables (mean ± SD) in ILD vs. ILD-S groups and adjusted hazard ratios with 95% confidence intervals (CI) for mortality risk. Subgroup analyses were stratified by sarcopenia diagnostic criteria, ILD subtype, and survival time. Heterogeneity was assessed using Cochran's Q and I2 statistics. Sensitivity analyses (leave-one-out) and publication bias assessments (Egger's test, trim-and-fill method) were performed.ResultsFourteen studies comprising 1,546 participants (628 with ILD-S) were included. Compared with ILD patients without sarcopenia, those with ILD-S were significantly older (WMD = 3.03, 95% CI: 2.12–3.93), had higher Gender-Age-Physiology (GAP) scores (WMD = 0.43, 95% CI: 0.15 to 0.71), and a higher FEV₁/FVC ratio (WMD = 1.97, 95% CI: 0.21 to 3.73, P = 0.03). Conversely, the ILD-S group showed lower values for FEV₁% predicted (WMD = −6.95, 95% CI: −9.80 to −4.09), FVC% predicted (WMD = −9.46, 95% CI: −12.04 to −6.88), DLCO% predicted (WMD = −5.87, 95% CI: −11.68 to −0.06), body mass index (WMD = −1.35, 95% CI: −1.89 to −0.82), handgrip strength (WMD = −12.80, 95% CI: −17.02 to −8.58), 6-minute walk distance (WMD = −31.01, 95% CI: −60.05 to −1.97), and appendicular skeletal muscle index (WMD = −1.45, 95% CI: −2.15 to −0.76). No significant difference was observed in smoking history. Sarcopenia was strongly associated with increased mortality risk (HR = 2.02, 95% CI: 1.67 to 2.45), and this association remained stable across different follow-up periods. Sensitivity and publication bias analyses confirmed the robustness of the findings.ConclusionPatients with ILD-S exhibit a distinctive profile characterized by older age, higher GAP scores, poorer pulmonary function, lower BMI, reduced muscle strength and mass, and significantly elevated mortality. Systematic recognition of these clinical features may facilitate early identification of ILD-S and inform the development of targeted interventions to improve patient outcomes.Systematic Review Registrationhttps://inplasy.com/, INPLASY202570030.