Electrocardiographic abnormalities and associated factors in Chinese living in Beijing and in Mauritius

Objective - To compare the prevalence of electrocardiographic abnormalities and to evaluate the association between these abnormalities and the levels of coronary heart disease among Chinese living in different environments. Design - Cross sectional surveys. Setting - Beijing, China, and the island of Mauritius. Subjects - Random samples of people aged 35-64 years in Beijing (621 men, 642 women) in 1984 and in Mauritius among Chinese (137 men, 130 women) and non-Chinese (1265 men, 1432 women) in 1987. Main outcome measures - Prevalence of electrocardiographic abnormalities suggesting coronary heart disease and of associated risk factors. Results - Prevalence of electrocardiographic abnormalities suggesting coronary heart disease was significantly lower in Beijing (4·0%) than in Mauritian Chinese (24·3%) and Mauritian non-Chinese (24·5%). Mean serum concentrations of total and non-high density lipoprotein cholesterol were lower in Beijing Chinese than in Mauritian Chinese, but smoking and hypertension were slightly more prevalent. Overall, men with electrocardiographic abnormalities had higher risk factor levels than those with a normal electrocardiogram regardless of ethnic origin. Conclusions - The prevalence of coronary heart disease and associated risk factors was different among Chinese living in two different environments: in Beijing in the People's Republic of China and in Mauritius. Chinese, who traditionally have a very low frequency of coronary heart disease, are by no means protected against coronary heart disease and other non-communicable diseases. Therefore, primary prevention of coronary heart disease is a major challenge for preventive medicine in China, as well as in many other developing countries.