Evaluation of depressive symptoms in patients with coronary artery disease using the Montgomery Åsberg Depression Rating Scale

Abstract

The aim of this study was to evaluate, in patients with coronary artery disease (CAD), factor structure and psychometric properties of the Montgomery Åsberg Depression Rating Scale (MADRS) to identify patients with current major depressive episode (MDE). The construct validity of the MADRS against self-rating scales was also evaluated. Consecutive 522 CAD patients at admission to the cardiac rehabilitation program were interviewed for the severity of depressive symptoms using the MADRS and for current MDE using the structured MINI International Neuropsychiatric Interview. Also, all patients completed the Hospital Anxiety and Depression Scale and the Beck Depression Inventory-II. The MADRS had one-factor structure and high internal consistency (Cronbach's coefficient α=0.82). Confirmative factor analysis indicated an adequate fit: comparative fit index=0.95, normed fit index=0.91, and root mean square error of approximation=0.07. At a cut-off value of 10 or higher, the MADRS had good psychometric properties for the identification of current MDE (positive predictive value=42%, with sensitivity=88% and specificity=85%). There was also a moderate to strong correlation of MADRS scores with scores on self-rating depression scales. In sum, in CAD patients undergoing rehabilitation, the MADRS is a unidimensional instrument with high internal consistency and can be used for the identification of depressed CAD patients. The association between MADRS and self-rating depression scores is moderate to strong.