Infection, depression, and immunity in women after coronary artery bypass: a pilot study of cognitive behavioral therapy

Abstract

Context: Depression is common after coronary artery bypass graft (CABG) surgery, but little is known about its effect on post-CABG inflammation or infection or about the most effective treatment for post-CABG depression.

Objectives: (1) To determine ifpost-CABG depression is associated with increased infectious illness and (2) to test effects of cognitive behavioral therapy (CBT) on depressive symptoms, inflammatory biomarkers, and post-CABG infections in depressed post-CABG women.

Design: Randomized, controlled trial.

Setting: Two urban tertiary care centers.

Patients: Fifteen clinically depressed women in the first month after CABG, along with a comparison group of 37 non-depressed postCABG women, were studied. Inclusion criteria were: < or = 75 years old, English-speaking, undergoing first-time CABG, available for 6 months offollow-up, and without malignancy or autoimmune disorders.

Intervention: Eight weeks of individual home-based CBT.

Main outcome measures: (1) Depressive symptoms measured by the Beck Depression Inventory, (2) natural killer cell cytotoxicity (NKCC) measured by 51Cr-release assay, (3) infectious illness episodes measured by the Modified Health Review, (4) interleukin (IL)-6 and C reactive protein (CRP) measured by enzyme immunoabsorbent assay.

Results: Clinically depressed post-CABG women exhibited decreased NKCC and a higher incidence of in-hospital fevers and infectious illness in the first 6 months after CABG. Among depressed women, CBT yielded moderate to large effects for improved NKCC (D=0.67) and decreased IL-6 (D=0.61), CRP (D=0.85), and postoperative infectious illnesses (D=0.93). CBT holds promise for improving depression and immunity and reducing infection and inflammation after CABG.