To determine whether the use and adjustment of antidepressant pharmacotherapy accounted for the beneficial effects of collaborative care treatment on the improvement of mood symptoms and health-related quality of life (HRQoL) after coronary artery bypass graft (CABG) surgery.

In a post-hoc analysis of data from the Bypassing the Blues (BtB) trial we tested the impact of antidepressant medication on changes in depression and HRQoL from the early postoperative period to 8-month follow-up. Two hundred fifty-nine depressed post-CABG patients scoring ≥ 10 on the Patient Health Questionnaire-9 were classified in four groups according to whether or not they received antidepressants at baseline and 8-months following randomization.

Patients using antidepressant pharmacotherapy at baseline and follow-up tended to be younger and female (p≤0.01), but were similar in various clinical characteristics. Just 24% (63/259) of patients were on an antidepressant at baseline which increased to 36% at follow-up (94/259). Compared to other groups, patients on antidepressants at both baseline and follow-up assessment showed the smallest improvement in mood symptoms and HRQoL. While multivariate analyses confirmed that randomization to collaborative care was associated with greater improvement in mood symptoms (odds ratio [OR] = 3.1; 95%-confidence interval [CI] = 1.8–5.4, p < 0.0001) and mental HRQoL (OR = 3.6, CI = 1.4–9.3, p = 0.01), use of antidepressant medication had no differential impact on either measure (p = 0.06 and p = 0.92, respectively).

The beneficial effects of collaborative care for post-CABG depression were not generated by adjustments in antidepressant medication.

Trial Registration: Clinicaltrials.gov Identifier: NCT00091962.

(http://clinicaltrials.gov/ct2/show/NCT00091962?term=rollman+cabg&rank=1).