In Thepa district, Songkhla province, Southern Thailand, parents of children being followed long term from conception for their development (N 1325), as well as health workers of the same district (N 150) were surveyed with regards to anthropometry, occupation, family size, food and leisure habits, and blood levels of lipids, sugar, creatinine and hematocrit. Differences among those of Thai or Chinese extracts (Thai-Buddhists) and those of Malay extracts (Thai-Muslims) were separately evaluated for males and females. The mean age for the group (N 1475, including 636 couples) was 31.5 + 7.3 (SD) and ranged from 15-66 years. There were 794 females (485 Muslims) ages 29.6 + 6.6 (SD). The Muslim families were larger in size averaging 2.8 + 1.6 children while the Buddhist’s averaged 1.9 + 0.9. Fifty four percent of the group were engaged in rubber tapping and this often included both members of the family. Sixty eight percent of the males currently smoked. Differences in measured variables between Muslims and Buddhists were minimal. The most striking however was the high density lipoprotein cholesterol (HDL-C) among the males where the ageadjusted average was 51.3 + 0.72 (SE) among the Buddhists and 42.2 + 0.59 (SE) in the Muslims. This
difference was significant even when adjusted for other related variables. Differences in the ethnic groups were also examined in terms of prevalence of risks (hypertension, BMI > 25%, waist-hip-ratio, fasting plasma glucose > 110 mg%, total cholesterol > 200 mg%, triglyceride > 150 mg% and low HDL-C). For hypertension (systolic > 140 or diastolic > 90 mmHg), female Muslims showed higher prevalence (4.5% vs 1.6%; OR 2.82 CI 1.04-7.64). For low HDL-C, male Muslim showed higher prevalence 23.6 vs 8.8%, OR 2.31 CI 1.27-4.22). Other risks showed no differences among the ethnic groups. The differences in parameters or in prevalence of risk between these two ethnic groups (minimal intermarriage) are distinct from differences
among Malays and Chinese in Singapore where such differences were subsequently reflected in the differences
in incidence and out-come of ischemic heart diseases.

Keywords: Cardiovascular risk factors, Ethnic differences