Association between depression and low skeletal muscle mass in patients with newly diagnosed lung cancer

Depression and reduced muscle mass are common in patients with lung cancer, and both are associated with adverse clinical outcomes. However, data examining their interrelationship remain limited.

This cross-sectional study included 100 patients with newly diagnosed lung cancer undergoing systemic therapy. Depressive symptoms were assessed using the Beck Depression Inventory (BDI). Skeletal muscle mass was evaluated using computed tomography (CT)-derived skeletal muscle index (SMI) at the L3 vertebral level. Clinical and demographic variables were analyzed for associations with depression.

Clinically relevant depressive symptoms were identified in 71% of patients, and CT-defined low skeletal muscle mass (LSMM) was present in 67% of patients. Scores on BDI were significantly and inversely correlated with total muscle area (TMA; r = -0.418, p < 0.001) and skeletal muscle index (r = -0.358, p < 0.001). In age-adjusted multivariate analysis, low SMI (OR 3.05, 95% CI 1.15-8.09) and higher Charlson Comorbidity Index (CCI) values (OR 3.27, 95% CI 1.25-8.68) were independently associated with depression.

Depressive symptoms are highly prevalent in lung cancer and are independently associated with CT-defined LSMM and a higher comorbidity burden. Routine assessment of SMI on staging CT scans may help identify patients at increased risk and support early multidisciplinary interventions.