High prevalence of metabolic syndrome among men in Okinawa.

We determined the prevalence of metabolic syndrome (MS) in Okinawa from cross-sectional results of an annual physical checkup. We also calculated the homeostasis model assessment ratio (HOMA-R) as an index of insulin resistance, and examined the relationship between HOMA-R and MS. We studied 3,839 men (mean age 49.2 years) and 3,146 women (mean age 50.0 years), a total of 6,985 people aged from 30 to 79 years, who underwent an annual physical checkup in our hospital between May 2003 and March 2004. The diagnosis of MS was based on the criteria in the Third Report of the National Cholesterol Education Program Expert Panel on Detection, Evaluation, and Treatment of High Blood Cholesterol in Adults (Adult Treatment Panel III: ATP III). Abdominal circumference was assessed in accordance with the diagnostic criteria of the Japan Society for the Study of Obesity. The prevalence of MS was 30.2% in men and 10.3% in women. Mean HOMA-R significantly increased with an increase in the number of ATP III risk factors. Logistic regression analysis with the independent variables of sex, age, and HOMA-R gave an odds ratio of MS of 3.6 for men, 1.4 for a 10-year age increment, and 2.0 for an elevation of HOMA-R above 1.0.