Objective: Prognostic studies of mortality in patients with COPD have mostly focused on physiologic variables, with little attention to depressive symptoms. This stands in sharp contrast to the attention that depressive symptoms have been given in the outcomes of patients with other chronic health conditions. The present study investigated the independent association of depressive symptoms in stable patients with COPD with all-cause mortality.
Methods: The baseline characteristics of 121 COPD patients (78 men and 43 women; mean [+/- SD] age, 61.5 +/- 9.1 years; and mean FEV(1), 36.9 +/- 15.5% predicted) were collected on hospital admission to a pulmonary rehabilitation center. The data included demographic variables, body mass index (BMI), post-bronchodilator therapy FEV(1), and Wpeak (peak workload [Wpeak]). Depressive symptoms were assessed using the Beck depression inventory. The vital status was ascertained using municipal registrations. In 8.5 years of follow-up, 76 deaths occurred (mortality rate, 63%). Survival time ranged from 88 days to 8.5 years (median survival time, 5.3 years). The Cox proportional hazard model was used to quantify the association of the baseline characteristics (ie, age, sex, marital status, smoking behavior, FEV(1), BMI, Wpeak, and depressive symptoms) with mortality.
Results: Depressive symptoms (odds ratio [OR], 1.93; 95% confidence interval [CI], 1.12 to 3.33) were associated with mortality in patients with COPD, independent of other factors including male sex (OR, 1.73; 95% CI, 1.03 to 2.92), older age (OR, 1.05; 95% CI, 1.02 to 1.08), and lower Wpeak (OR, 0.98; 95% CI, 0.97 to 0.99).
Conclusions: This study provides evidence that depressive symptoms assessed in stable patients with COPD are associated with their subsequent all-cause mortality.