Cardiovascular disease prevalence and insulin resistance in the Kyushu–Okinawa Population Study and the Framingham Offspring Study

Background Age-adjusted cardiovascular disease (CVD) prevalence rates are significantly lower in Japan than in the United States. Objective Our aim was to compare CVD risk in participants in Fukuoka and Framingham. Methods We measured glucose, insulin, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol (LDL-C), small dense LDL-C, and triglycerides in men and women from Fukuoka (n = 1108), and age (median, 53 years) and gender-matched subjects from Framingham (n = 1101). Blood pressure, body mass index, use of medications, and history of CVD were also assessed. Results CVD prevalence rates were more than 6-fold higher in Framingham men and women than their Fukuoka counterparts (P < .001). Median body mass index, LDL-C, insulin levels, and insulin resistance assessment in Fukuoka men and women were significantly (P < .01) lower than in Framingham; however, diabetes prevalence in Fukuoka men was significantly (P < .01) higher than in Framingham men, whereas female rates were similar, as were levels of systolic blood pressure. High-density lipoprotein cholesterol and surprisingly small dense LDL-C levels were significantly (P < .001) higher in Fukuoka than in Framingham. Standard risk factors do not account for the large differences in CVD prevalence rates between the 2 populations, and population differences in insulin resistance may explain some of these differences. Conclusions Our data are consistent with the concept that the CVD prevalence rate in a Japanese population is much lower than those observed in the United States, and that these differences cannot be explained by standard CVD risk factors, but may relate to marked population differences in insulin resistance.