To examine the utility and validate the use of the Cardiac Depression Scale in patients who had first-time coronary artery bypass graft surgery.Background.
The Beck Depression Inventory, though frequently used, may not be sufficiently sensitive for use in cardiac patients. The Cardiac Depression Scale has been shown to identify the range of depression in medical cardiac patients.Design.
The Beck Depression Inventory and Cardiac Depression Scale were administered to 120 men at hospital discharge, as well as six, 12 and 36 weeks postoperatively. Cronbach's α scores were calculated for the measures at each point. Changes in scores over time were analysed using repeated measures analysis of variance. Associations between the measures scores were calculated using Pearson product–moment correlations. Agreement between the measures' dichotomised scores (depression/no depression) was examined using Cohen's Kappa statistic.Results.
Internal consistency was similar for the Beck Depression Inventory (0·793–0·904) and Cardiac Depression Scale (0·859–0·910). Depression scores decreased over time with the Beck Depression Inventory [F(2·50, 175·29) = 22·27, p < 0·001] and Cardiac Depression Scale [F(2·68, 190·37) = 13·18, p < 0·001]. The measures had similar power [Cohen's f = 0·65 (Beck Depression Inventory) and 0·43 (Cardiac Depression Scale)] to reveal changes over time. The continuous scores were highly correlated at each point [0·737 (p < 0·001)–0·819 (p < 0·001)]. However, when dichotomised scores were compared, the chance corrected level of agreement was less impressive [0·198 (p = 0·014)–0·381 (p < 0·001)].Conclusions.
The Cardiac Depression Scale may have utility for use with surgical cardiac patients. However, continued examination of this measure of depression is warranted.Relevance to clinical practice.
Given the prevalence of depression and its negative impact on coronary artery disease, it is important to identify even mild depression in cardiac patients. Using a measure of depression specifically for cardiac patients, rather than a generic measure, may best accomplish this goal.