A 3-year follow-up study of coronary heart disease in Delhi.

A follow-up study of coronary heart disease (CHD) was carried out among adults in Delhi 3 years after an initial community-based epidemiological survey of the same population. A total of 575 of the 814 cases of CHD detected clinically and by electrocardiogram (ECG) in the initial survey took part. On re-examination of the original cohort of 4151 adults who were free of CHD both clinically and by ECG in the initial survey, 245 new cases of CHD were detected - 73 on a clinical basis (21 with myocardial infarction and 52 with angina pectoris) and 172 by ECG (13 with myocardial infarction and 159 with probable CHD based on ST and T changes). The overall incidence of CHD was 19.7 per 1000 (males, 17.3 per 1000; females, 21.0 per 1000). The incidence on a clinical basis was 5.9 per 1000 (males, 6.5 per 1000; females, 5.5 per 1000) compared with 13.8 per 1000 by ECG (males, 10.8 per 1000; females, 15.5 per 1000). Although the incidence of myocardial infarction was higher in men (3.6 per 1000) than women (2.2 per 1000), the incidence of angina pectoris was 36.5% higher in women (18.7 per 1000) than in men (13.7 per 1000). Hypercholesterolaemia and systemic hypertension were the commonest risk factors in the 245 new cases.