Epidemiologic assessment of angina before and after myocardial infarction: The Framingham study.

Angina pectoris before and after MI was evaluated in a sample of 729 men and women from a general population in whom MI developed during a 36-year period of follow-up. Relations of AP to subsequent CHD events and mortality after initial MI were analyzed by proportional hazards regression models and were adjusted for covariates (age, sex, blood pressure, serum cholesterol, body mass index, glucose intolerance, cigarette smoking, and antihypertensive medications) obtained from routine biennial examinations preceding the initial MI. Comparisons of the influence of angina were made between pre-MI angina, post-MI angina, and absence of AP. The sample had 484 men and 245 women (mean ages, 63 and 69, respectively) who survived greater than / equal to 30 days after MI. The initial MI was clinically unrecognized in 165 (34%) men and 115 (47%) women. Data on covariates were complete for 622 subjects, among whom 30% had pre-Ml angina, 18% had post-MI angina, and 52% did not have AP. Angina was half as common in persons with unrecognized MIs as in those with clinically recognized MIs. During an average of 8.7 years of follow-up, 57% of subjects developed subsequent CHD events, including recognized and unrecognized MI, coronary insufficiency, and CHD death, and 74% died. Both pre-MI angina (hazard ratio, 1.49; 95% CI, 1.17 to 1.91) and post-MI angina (hazard ratio, 1.43; 95% CI, 1.06 to 1.94) adjusted for accompanying risk factors were associated with increased risk for subsequent CHD events compared with those without AP. Neither pre-MI nor post-MI angina was associated with excess overall mortality.