Type A behavior and myocardial infarction. A 9.5-year follow-up of a small cohort.

To test the hypothesis that type A behavior is associated with the incidence of myocardial infarction in groups outside the U.S.A., 243 healthy males, aged 45-59 years, who participated in the Kaunas-Rotterdam Intervention Study (KRIS) were interviewed and followed for 91/2 years. No association between type A behavior and the incidence of all coronary events (myocardial infarction and cardiac death) was found. Fatal coronary events, however, were found to have occurred in types A only (P = 0.04). This weak, but positive association indicates that in Europe too the incidence of fatal coronary heart disease is associated with type A behavior.