Long-term survival of patients with chronic obstructive pulmonary disease undergoing coronary artery bypass surgery.

ABSTRACT

BACKGROUND: Chronic obstructive pulmonary disease (COPD) is associated with increased in-hospital mortality in patients undergoing coronary artery bypass surgery (CABG). Long-term survival is less well understood. The present study examined the effect of COPD on survival after CABG. METHODS AND RESULTS: We conducted a prospective study of 33,137 consecutive isolated CABG patients between 1992 and 2001 in northern New England. Records were linked to the National Death Index for long-term mortality data. Cox proportional hazards regression was used to calculate hazard ratios (HRs). Patients were stratified by no comorbidities (none), COPD, COPD plus comorbidities, and other comorbidities with no COPD. There were 131,434 person years of follow-up and 5344 deaths. The overall incidence rate (deaths per 100 person years) was 4.1. By group, rates were 2.1 (none), 4.0 (COPD alone), 5.5 (other), and 9.4 (COPD plus; log rank P<0.001). After adjustment, survival with COPD alone was worse compared with none (HR, 1.8; 95% CI, 1.6 to 2.1; P<0.001). Patients with other comorbidities compared with none had even worse survival (HR, 2.2; 95% CI, 2.1 to 2.4; P<0.001). Patients with COPD plus other comorbidities compared with none had the worst long-term survival (HR, 3.6; 95% CI, 3.3 to 3.9; P<0.001). CONCLUSIONS: Patients with only COPD had significantly reduced long-term survival compared with patient with no comorbidities. Patients with COPD and > or = 1 other comorbidity had the worst survival rate when compared with all of the other groups.