β-blockers improve survival of patients with chronic obstructive pulmonary disease after coronary artery bypass grafting

Background. beta-Blockers are known to improve survival of patients with cardiovascular disease, but their administration in patients with chronic obstructive pulmonary disease (COPD) remains controversial. The aim of the present study was to assess the effect of beta-blocker administration in patients with COPD undergoing coronary artery bypass grafting. Methods. A total of 388 consecutive patients with COPD who underwent isolated coronary artery bypass grafting were studied, and clinical follow-up was completed. Diagnosis of COPD was based on preoperative forced expiration volume; exacerbation episodes were defined as a pulsed-dose prescription of prednisolone or a hospital admission for an exacerbation. Two propensity-matched cohorts of 104 patients each either receiving or not receiving beta-blockers were identified. Results. At baseline, there was no significant difference among groups. After a median follow-up of 36 months, there were 8 deaths in 104 patients (7.7%) receiving beta-blockers versus 19 deaths in 104 patients (18.3%) who did not receive beta-blockers (p = 0.03). Kaplan-Meyer analysis showed a survival of 91.8% +/- 2.8% for patients taking beta-blockers versus 80.6% +/- 4.0% for control subjects (chi(2), 29.4; p = 0.003; hazard ratio, 0.38). In addition, beta-blocker administration did not increase rates of COPD exacerbation, which was experienced by 46 of 104 patients (44.2%) receiving beta-blockers versus 45 of 104 patients (43.3%) not receiving beta-blockers (p = 0.99). Conclusions. This study showed that in patients with COPD undergoing coronary artery bypass grafting the administration of beta-blockers is safe and significantly improves survival at mid-term follow-up. Further randomized studies are needed to confirm these findings. (Ann Thorac Surg 2013;95:525-32) (c) 2013 by The Society of Thoracic Surgeons