Incidence and patterns of depression following coronary artery bypass graft surgery.

A number of studies have examined the impact of coronary artery bypass graft surgery (CABG) on mood by means of cross-sectional analyses. These studies have provided a "snapshot" view of the numbers of patients showing psychological disturbance. To examine both the incidence and patterns of depression, 121 patients undergoing routine elective CABG were assessed preoperatively and postoperatively at 8 days, 8 weeks, and 12 months on the Beck Depression Inventory (BDI). The incidence findings suggested a small, transient increase in the number of patients with depression shortly after surgery. The preoperative score on the BDI was the best predictor of postoperative depression at all times of measurement. Discriminant function analysis on the patterns of depression indicated that trait anxiety maximally separated those patients who were depressed pre- and postoperatively from those only depressed shortly after the operation. The findings emphasize the value of examining patients' levels of anxiety and depression prior to surgery.