The prevalence of coronary heart disease (CHD) and its risk factors in first-generation Asian Indian immigrants to the United States of America (US) were compared with those of the native Caucasian population. A total of 1688 Asian Indian physicians and their family members (1131 men and 557 women, age > or = 20 years) completed a questionnaire and in 580 subjects serum lipoproteins were determined. The age-adjusted prevalence of myocardial infarction and/or angina was approximately three times more in Asian Indian men compared to the Framingham Offspring Study (7.2% versus 2.5%; P < 0.0001) but was similar in women (0.3% versus 1%; p = 0.64). Asian Indians had higher prevalence of noninsulin-dependent diabetes mellitus (NIDDM; 7.6% versus 1%; p < 0.0001) but markedly lower prevalence of cigarette smoking (1.3% versus 27%; p < 0.0001) and obesity (4.2% versus 22%; p < 0.0001). Hypertension was less prevalent in Asian Indian men 14.2% versus 19.1%, p < 0.008) but similar in women (11.3% versus 11.4%). The prevalence of elevated total a low-density lipoprotein (LDL) cholesterol levels was similar in men [17% versus 23.4% (p = 0.24) and 13.7% versus 22.3% (p = 0.22), respectively] but lower in women [15% versus 26.1% (p = 0.018) and 14.3% versus 19.6% (p = 0.047) respectively]. The mean levels of high-density lipoprotein (HDL) cholesterol were less in younger (30-39 years) Asian Indian men (mean: 0.98 versus 1.18 mmol/l; p < 0.001) and middle-aged (30-59 years) women (mean: 1.24 versus 1.45 mmol/l; p < 0.001). The prevalence of hypertriglyceridaemia was similar in men (18.5% versus 11.3%), but higher in Asian Indian women (8.3% versus 4.1%, p = 0.02). To conclude, immigrant Asian Indian men to the US have high prevalence of CHD, NIDDM, low HDL cholesterol levels and hypertriglyceridaemia. All these have "insulin resistance" as a common pathogenetic mechanism and seem to be the most important risk factors.