title: Are coronary-care unit changes in therapy associated with improved survival of elderly patients with acute myocardial infarction?
abstract: OBJECTIVE
  To determine whether changes in coronary-care unit therapy for elderly patients with acute myocardial infarction have been associated with improved survival.
  
  
  METHODS
  We conducted a retrospective cohort analysis of all patients 70 years of age or older from Olmsted County, Minnesota, who were hospitalized in a coronary-care unit in this county for the treatment of acute myocardial infarction during one of three periods: 1976 through 1978, 1987 through 1989, and 1991. The effect of aspirin, heparin, beta-blockers, thrombolysis, percutaneous transluminal coronary angioplasty, and coronary artery bypass grafting on these elderly patients with acute myocardial infarction was assessed.
  
  
  RESULTS
  Improvement in 30-day survival was significant for patients 80 years of age or older (45%, 69%, and 78% in 1976 through 1978, 1987 through 1989, and 1991, respectively; P = 0.01 for the trend) but not for patients 70 to 79 years of age (77%, 76%, and 81% for the three time periods, respectively; P = 0.65 for the trend). The opposite pattern was observed for survival in the period more than 30 days after the event. More intensive treatment in the hospital was associated with better 30-day survival (P < 0.0001).
  
  
  CONCLUSIONS
  The improved survival of the elderly patients with acute myocardial infarction in these cohorts can be accounted for by changes in the therapy they received in the coronary-care units.
authors.affiliation: Division of Cardiovascular Diseases and Internal Medicine, Mayo Clinic Rochester, Minnesota 55905, USA.
authors.forename: H
authors.initials: H
authors.lastname: Daida
authors.forename: T E
authors.initials: TE
authors.lastname: Kottke
authors.forename: R J
authors.initials: RJ
authors.lastname: Backes
authors.forename: B J
authors.initials: BJ
authors.lastname: Gersh
authors.forename: E G
authors.initials: EG
authors.lastname: Tangalos
authors.forename: K R
authors.initials: KR
authors.lastname: Bailey
mesh_terms: D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D015906:Angioplasty, Balloon, Coronary; D006328:Cardiac Catheterization; D017023:Coronary Angiography; D001026:Coronary Artery Bypass; D003325:Coronary Care Units; D005260:Female; D006801:Humans; D008297:Male; D009203:Myocardial Infarction / Q000175:diagnosis / Q000188:drug therapy / Q000401:mortality / Q000601:surgery / Q000628:therapy*; D016016:Proportional Hazards Models; D012189:Retrospective Studies; D012720:Severity of Illness Index; D016019:Survival Analysis; D016896:Treatment Outcome