title: Prognosis after first myocardial infarction. Comparison of Q-wave and non-Q-wave myocardial infarction in the Framingham Heart Study.
abstract: OBJECTIVE
  To compare the short- and long-term prognosis following a first Q-wave or non-Q-wave myocardial infarction.
  
  
  METHODS
  Cohort study with a mean follow-up period of 5.1 +/- 4.9 years.
  
  
  METHODS
  Population-based.
  
  
  METHODS
  Framingham (Mass) Heart Study subjects with an initial recognized myocardial infarction during a 17-year period were studied, including 227 men and 136 women with a mean age of 67.2 years. Seventy-seven percent of first infarctions were Q-wave infarctions and 23% were non-Q-wave infarctions.
  
  
  METHODS
  Reinfarction and death from coronary heart disease.
  
  
  RESULTS
  During the follow-up period, subjects with non-Q-wave infarctions had a significantly higher rate of reinfarction than subjects in the Q-wave group (P = .02 for the entire follow-up). The 10-year reinfarction rates were 44.8% vs 27.4%. When analyzed separately by age and sex, differences in reinfarction rates were only noted in men and in those under the age of 65 years. There were no differences in coronary heart disease death rates based on Q-wave status, even when examined separately by age and sex. Multivariate analysis revealed a 1.8-fold higher risk of reinfarction in the non-Q-wave group (95% confidence interval, 1.1 to 3.1), and also demonstrated that baseline hypertension was an independent risk factor for predicting reinfarction (relative risk, 1.8; 95% confidence interval, 1.1 to 3.2). There were no differences in the rates of sudden death or all-cause mortality following the two types of myocardial infarction. Additionally, subjects with a first Q-wave infarction had a higher rate of subsequent congestive heart failure, while those with non-Q-wave infarctions had a significantly higher rate of coronary insufficiency (unstable angina with transient ST-T wave abnormalities).
  
  
  CONCLUSIONS
  These results confirm and extend findings from prior studies that have identified patients with first non-Q-wave myocardial infarctions as potentially unstable, with greater subsequent morbidity and similar mortality to their counterparts with Q-wave infarctions.
authors.affiliation: Cardiovascular Division, Beth Israel Hospital, Boston, Mass.
authors.forename: C J
authors.initials: CJ
authors.lastname: Berger
authors.forename: J M
authors.initials: JM
authors.lastname: Murabito
authors.forename: J C
authors.initials: JC
authors.lastname: Evans
authors.forename: K M
authors.initials: KM
authors.lastname: Anderson
authors.forename: D
authors.initials: D
authors.lastname: Levy
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D004562:Electrocardiography; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015994:Incidence; D008297:Male; D008404:Massachusetts / Q000453:epidemiology; D008875:Middle Aged; D009017:Morbidity; D015999:Multivariate Analysis; D009203:Myocardial Infarction / Q000401:mortality / Q000503:physiopathology*; D011379:Prognosis; D011446:Prospective Studies; D012008:Recurrence; D012307:Risk Factors