Prevalence of metabolic syndrome compared between native Japanese and Japanese-Americans

Metabolic syndrome is a condition characterized by the accumulation of multiple risk factors for atherosclerosis. Japanese-Americans in the U.S. have a more rapid and intense progression of atherosclerosis than native Japanese in Japan due to a westernization of their lifestyle. We investigated the prevalence of metabolic syndrome between 416 native Japanese (194 men and 222 women) in Hiroshima and 574 Japanese-Americans (217 men and 357 women) in Los Angeles, aged 30-89 years. According to the criteria proposed by the Japanese Society of Internal Medicine, the prevalence was 13.9 and 2.7% for native Japanese men and women, and 32.7 and 3.4% for Japanese-American men and women, respectively. According to the IDF or AHA/NHLBI criteria, the prevalence was 20.1 and 6.3%, and 38.7 and 4.5%, or 13.4 and 14.4%, and 30.9 and 27.7%, respectively. Thus, the prevalence of metabolic syndrome in men was significantly higher in Japanese-American than in native Japanese by all the three criteria. However, the prevalence in women was similar between native Japanese and Japanese-American by the Japanese and IDF criteria, whereas it was significantly higher in Japanese-American than in native Japanese by the AHA/NHLBI criteria. This report demonstrates that a westernization of lifestyle can increase the prevalence of metabolic syndrome among Japanese-Americans as compared to native Japanese.