Cardiovascular risk factor levels in urban and rural Thailand - The International Collaborative Study of Cardiovascular Disease in Asia (InterASIA)

Background Vascular mortality is increasing in economically developing countries but reliable data about the determinants of cardiovascular disease are few. The International Collaborative Study of Cardiovascular Disease in Asia (InterASIA) was designed to obtain,precise estimates of cardiovascular risk factor levels in the adult population of Thailand. Design A complex sample survey. Methods Data from a structured questionnaire, brief physical examination and a blood sample were collected from 5305 individuals aged 35 years or older (response rate 68%). Mean risk factor levels were calculated for eight groups defined by age and sex in 18 representative urban and rural areas of Thailand. Population risk factor levels were calculated by applying sampling weights derived from the 2000 Thai Census and allowing for the complex sampling design. Results The estimated mean (standard error) population blood pressure was 120/76 (0.7/0.5) mmHg, mean serum total cholesterol was 5.2 (0.06) mmol/l, mean body mass index was 24 (0.2) kg /m(2), mean fasting plasma glucose was 5.6 (0.06) mmol/l, the proportion with diabetes 9.6 (1)% and the proportion of current smokers was 25 (3)%. There were estimated to be 5.1 (0.5) million individuals with high blood pressure, 4.4 (0.4) million with high total cholesterol, 8.9 (0.8) million overweight or obese, 2.4 (0.2) million with diabetes and 6.2 (0.9) million current smokers. Mean levels of all major risk factors, except smoking, were worse in urban compared with rural areas. However, except for total cholesterol, the absolute numbers of individuals with abnormal risk factor levels were highest in rural areas. Conclusion Absolute levels of cardiovascular risk factors in Thailand are high. Effective risk factor control strategies that target both rural and urban areas of Thailand have the potential to avert much premature cardiovascular disease. (C) 2003 Lippincott Williams Wilkins.