Relationship between depression in patients with COPD and the percent of predicted FEV(1), BODE index, and health-related quality of life

We investigated the prevalence of depression among patients with COPD treated in long-term in-patient rehabilitation facilities, using the Center for Epidemiologic Studies Depression scale (CES-D). Furthermore, the relationship between the severity of air-flow obstruction (the percent of predicted FEV(1)), BODE (body mass index, degree of air-flow obstruction, dyspnea, exercise capacity) index, health-related quality of life (St George's Respiratory Questionnaire [SGRQ]), and depression were investigated. We recruited 74 in-patients (64 males, 10 females) with COPD. The mean age of the subjects was 72.7 years (range 52-85 y). Subjects completed the CES-D, and measurements were made of pulmonary function, body mass index, Modified Medical Research Council dyspnea scale, 6-min walk test (6MWT), and SGRQ. Depression was evident in 48.6% (n = 36) of the subjects. A weak correlation was found between the CES-D scores and the percent of predicted FEV(1). The prevalence of depression showed a significant association with BODE stage. Scores for the SGRQ activity and impacts domains, and total SGRQ score were significantly worse in the subjects who were depressed. We found a high prevalence of depression among patients with stable COPD treated in long-term in-patient rehabilitation facilities. Depression among these patients, as measured by the CES-D, was associated with greater impairment in respiratory function and with poorer Modified Medical Research Council dyspnea scale and SGRQ scores. The prevalence of depression increased with BODE stage.