title: Association between older age and outcome after cardiac surgery: a population-based cohort study.
abstract: OBJECTIVE
  Octogenarians (aged ≥ 80 years) are increasingly being referred for cardiac surgery. We aimed to describe the morbidity, mortality, and health services utilization of octogenarians undergoing elective cardiac surgery.
  
  
  METHODS
  Retrospective population-based cohort study of adult patients receiving elective cardiac surgery between January 1 2004 and December 31 2009. Primary exposure was age ≥80 years. Outcomes were 30-day, 1- and 5-year mortality, post-operative complications, and ICU/hospital lengths of stay. Multi-variable logistic and Cox regression analyses were used to explore the association between older age and outcome.
  
  
  RESULTS
  Of 6,843 patients receiving cardiac surgery, 544 (7.9%) were octogenarians. There was an increasing trend in the proportion of octogenarians undergoing surgery during the study period (0.3% per year, P = 0.073). Octogenarians were more likely to have combined procedures (valve plus coronary artery bypass or multiple valves) compared with younger strata (p < 0.001). Crude 30-day, 1-year and 5-year mortality for octogenarians were 3.7%, 10.8% and 29.0%, respectively. Compared to younger strata, octogenarians had higher adjusted 30-day (OR 4.83, 95%CI 1.30-17.92; P = 0.018) and 1-year mortality (OR 4.92; 95% CI, 2.32-10.46. P<0.001). Post-operative complications were more likely among octogenarians. Octogenarians had longer post-operative stays in ICU and hospital, and higher rates of ICU readmission (P < 0.001 for all). After multi-variable adjustment, age ≧ 80 years was an independent predictor of death at 30-days and 1 year.
  
  
  CONCLUSIONS
  Octogenarians are increasingly referred for elective cardiac surgery with more combined procedures. Compared to younger patients, octogenarians have a higher risk of post-operative complications, consume greater resources, and have worse but acceptable short and long-term survival.
authors.affiliation: Division of Cardiac Surgery, Mazankowski Alberta Heart Institute, University of Alberta, Edmonton, Alberta, Canada. wei.wang@ualberta.ca.
authors.forename: Wei
authors.initials: W
authors.lastname: Wang
authors.affiliation: Division of Cardiac Surgery, Mazankowski Alberta Heart Institute, University of Alberta, Edmonton, Alberta, Canada. bagshaw@ualberta.ca.|Division of Critical Care Medicine, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Alberta, Canada. bagshaw@ualberta.ca.|Division of Critical Care Medicine, Clinical Sciences Building, 2-124E, 8440 - 112 Street, Edmonton, Alberta, T6G 2B7, Canada. bagshaw@ualberta.ca.
authors.forename: Sean M
authors.initials: SM
authors.lastname: Bagshaw
authors.affiliation: Division of Cardiac Surgery, Mazankowski Alberta Heart Institute, University of Alberta, Edmonton, Alberta, Canada. cnorris@ualberta.ca.|Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Alberta, Canada. cnorris@ualberta.ca.|Faculty of Nursing, University of Alberta, Edmonton, Alberta, Canada. cnorris@ualberta.ca.
authors.forename: Colleen M
authors.initials: CM
authors.lastname: Norris
authors.affiliation: Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Alberta, Canada. zibdawi@ualberta.ca.
authors.forename: Rami
authors.initials: R
authors.lastname: Zibdawi
authors.affiliation: Division of Cardiac Surgery, Mazankowski Alberta Heart Institute, University of Alberta, Edmonton, Alberta, Canada. Mohamad.Zibdawi@albertahealthservices.ca.|Division of Critical Care Medicine, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Alberta, Canada. Mohamad.Zibdawi@albertahealthservices.ca.
authors.forename: Mohamad
authors.initials: M
authors.lastname: Zibdawi
authors.affiliation: Division of Cardiac Surgery, Mazankowski Alberta Heart Institute, University of Alberta, Edmonton, Alberta, Canada. Roderick.MacArthur@albertahealthservices.ca.
authors.forename: Roderick
authors.initials: R
authors.lastname: MacArthur
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D006348:Cardiac Surgical Procedures / Q000401:mortality; D017558:Elective Surgical Procedures / Q000401:mortality; D005260:Female; D006801:Humans; D007362:Intensive Care Units / Q000706:statistics & numerical data*; D007902:Length of Stay / Q000706:statistics & numerical data*; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D017063:Outcome Assessment, Health Care; D011183:Postoperative Complications / Q000453:epidemiology / Q000209:etiology*; D016016:Proportional Hazards Models; D012189:Retrospective Studies; D055815:Young Adult