title: 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.
  
  
  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.
authors.affiliation: Fletcher Allen Health Care, 111 Colchester Ave, Burlington, VT 05401-1473, USA. bruce.leavitt@vtmednet.org
authors.forename: Bruce J
authors.initials: BJ
authors.lastname: Leavitt
authors.forename: Cathy S
authors.initials: CS
authors.lastname: Ross
authors.forename: Brian
authors.initials: B
authors.lastname: Spence
authors.forename: Stephen D
authors.initials: SD
authors.lastname: Surgenor
authors.forename: Elaine M
authors.initials: EM
authors.lastname: Olmstead
authors.forename: Robert A
authors.initials: RA
authors.lastname: Clough
authors.forename: David C
authors.initials: DC
authors.lastname: Charlesworth
authors.forename: Robert S
authors.initials: RS
authors.lastname: Kramer
authors.forename: Gerald T
authors.initials: GT
authors.lastname: O'Connor
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015897:Comorbidity; D001026:Coronary Artery Bypass / Q000706:statistics & numerical data; D003327:Coronary Disease / Q000150:complications / Q000453:epidemiology / Q000601:surgery*; D016208:Databases, Factual; D048909:Diabetes Complications / Q000601:surgery; D005260:Female; D005500:Follow-Up Studies; D006333:Heart Failure / Q000453:epidemiology; D006801:Humans; D007674:Kidney Diseases / Q000453:epidemiology; D015993:Life Tables; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000453:epidemiology; D010437:Peptic Ulcer / Q000453:epidemiology; D016491:Peripheral Vascular Diseases / Q000453:epidemiology; D015995:Prevalence; D016016:Proportional Hazards Models; D011446:Prospective Studies; D029424:Pulmonary Disease, Chronic Obstructive / Q000150:complications* / Q000453:epidemiology; D012042:Registries; D016019:Survival Analysis; D016896:Treatment Outcome