BACKGROUND: Recovery from coronary artery bypass graft (CABG) surgery often is complicated by depression and insomnia, resulting in poorer health-related quality of life and clinical outcomes. We explored the relationships among depression, insomnia, quality of life, and the impact of a collaborative care strategy on reducing insomnia in patients after CABG surgery.
METHODS: Patients with a Patient Health Questionnaire score ≥10 were randomized to nurse-delivered collaborative care for depression (n = 150) or their physician’s usual care (n = 152). A convenience sample of patients without depression (n = 151) served as the control group. Using the Hamilton Depression Rating Scale sleep questions, we created an “insomnia index.”
RESULTS: At baseline, 63% of participants who were depressed vs 12% of those who were not depressed reported insomnia. Compared with usual care, fewer collaborative care participants reported insomnia at 8 months, and they tended to have a lower insomnia score (insomnia index change score −0.95 and −1.47, respectively; P = .05) with no time-by-randomization interaction, Cohen’s d = 0.22 (95% confidence interval, −0.001 to 0.43). Participants with baseline insomnia reported greater improvements in mental health–related quality of life (Medical Outcomes Survey 36-item Short Form Mental Component Summary score; −3.32, P = .02), but insomnia was not a significant moderator of the effect of collaborative care.
CONCLUSIONS: This is the first study to examine the long-term impact on insomnia among post-CABG patients treated for depression. Future collaborative care studies could consider including a therapeutic focus for insomnia.