Factors Associated with Depression in COPD: A Multicenter Study.

Introduction: Depression is a prevalent comorbidity in COPD and has an impact on the prognosis of these patients, thereby making it important to study the factors associated with depression in patients with COPD.
Method: A multicenter, observational and cross-sectional study was conducted to study the factors associated with depression in patients with COPD measured by the hospital anxiety and depression (HAD) questionnaire. We analyzed anthropometric variables and the number of exacerbations in the previous year and calculated the 6-min walking test and the body mass index, airflow obstruction, dyspnea, and exercise (BODE) index. All the patients completed the quality of life EQ-5D and the LCADL physical activity questionnaires. The relationship of these variables with depression was evaluated with two multiple logistic regression models.
Results: One hundred fifteen patients were evaluated (93 % male) with a mean age of 66.9 years (SD 8.8) and a mean FEV1 % of 44.4 % (SD 15.7 %). 24.3 % presented symptoms of depression (HAD-D > 8). These latter patients had worse lung function, greater dyspnea, reduced exercise capacity, a higher score in the BODE index, poorer quality of life, reduced physical activity, and more exacerbations. In the first logistic regression model, quality of life and the BODE index were associated with depression (AUC: 0.84; 0.74-0.94). In the second model including the variables in the BODE index, quality of life and dyspnea measured with the MRC scale (AUC: 0.87; 0.79-0.95) were associated with depression.
Conclusions: Nearly one-quarter of the patients with COPD in this study presented clinically significant depression associated with worse quality of life, reduced exercise capacity, greater dyspnea, and a higher score in the BODE index.