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 ≥1 other comorbidity had the worst survival rate when compared with all of the other groups.