Prevalence of coronary artery disease and coronary risk factors in rural and urban populations of north India.

OBJECTIVE: This study was conducted to determine and compare the prevalence of coronary artery disease and coronary risk factors in both a rural and an urban population of Moradabad in north India.

DESIGN AND SETTING: A cross-sectional survey of two randomly selected villages from the Moradabad district and 20 randomly selected streets in the city of Moradabad.

SUBJECTS AND METHODS: The 3575 subjects were between 25 and 64 years old; 1769 (894 men and 875 women) lived in the countryside and 1806 (904 men and 902 women) lived in the city. The survey methods were questionnaires, physical examination and electrocardiography.

RESULTS: The overall prevalence of coronary artery disease, based on a clinical diagnosis and an electrocardiogram, was 9.0% in the urban and 3.3% in the rural population. The prevalences were significantly (P < 0.001) higher in the men compared with the women in both urban (11.0 vs 6.9%) and rural (3.9 vs 2.6%) populations, respectively. The prevalence of symptomatic coronary artery disease (known coronary disease and Rose questionnaire-positive angina) was 2.3% in the men (n = 19) and 1.5% in the women (n = 13) in the rural subjects, and 8.5% in the men (n = 77) and 3.4% in the women (n = 31) in the urban population. When diagnosed on the basis of electrocardiographic changes alone, the prevalences were 1.5% (n = 26) in the rural population and 3.0% (n = 55) in the urban. Coronary risk factors were two- or three-fold more common among urban subjects compared to the rural population in both sexes. Central obesity was four times more common in the urban population compared to the rural in both sexes. Sedentary lifestyle and alcohol intake were significantly (P < 0.01) higher in the urban population compared to the rural subjects. There was a significant association between coronary disease and age, hypercholesterolaemia, hypertension and central obesity in both sexes. Smoking was a significant risk factor of coronary disease in men.

CONCLUSIONS: Coronary artery disease and coronary risk factors were two or three times higher among the urban compared with the rural subjects, which may be due to greater sedentary behaviour and alcohol intake among urbans. It is possible that some Indian populations can benefit by reducing serum cholesterol, blood pressure and central obesity and increasing physical activity.