Effect of lifestyle on the prevalence of the metabolic syndrome among farmers, migrants with Yi ethnicity and Han population in Sichuan province of China.

Yi people are the most primitive society in China. Little information on the metabolic syndrome (MS) is available in Yi people. We explored whether differing lifestyle affected the prevalence of MS among farmers and migrants of Yi ethnicity and Han population in one of the Southwestern parts of China. The prevalence of MS among the three populations was described under the same International Diabetes Federation (IDF) criteria. The study populations comprised of 1,535 Yi farmers, 1,306 Yi migrants and 2,130 Han people. The effects of physical activity, obesity and other risk factor on MS were evaluated. Results showed that the age- and sex-adjusted prevalence of MS was 9.9 times higher in Yi migrants (23.8%) and 6.3 times higher in Han people (15.2%) than in Yi farmers (2.4%). In addition, the prevalence of MS increased significantly with age in both sexes, except for a slight increase in Yi farmers. The prevalence of overweight and obesity was much lower in Yi farmers (9.3% in men and 16.5% in women) than that in Yi migrants (46.2% in men and 34.8% in women) and Han people (40.6% in men and 31.9% in women). Levels of physical activity were much greater in Yi farmers than in Yi migrants and Han people. These results indicated that lifestyle had strongly influenced the development of MS in Han and Yi Chinese and our study provided one more piece of evidence imputing that high prevalence of MS might be related to a change in lifestyle associated with urbanization.