Correlations of adiponectin level with insulin resistance and atherosclerosis in Japanese male populations

OBJECTIVE Adiponectin, which is secreted specifically by adipose tissue, has been shown to have an anti-atherosclerotic effect and to improve insulin resistance. The aim of this study was to determine the correlations of plasma adiponectin concentration with insulin resistance and atherosclerosis. DESIGN AND METHODS We investigated the relationships of adiponectin concentration with insulin sensitivity, high-sensitivity C-reactive protein (hCRP) and pulse wave velocity (PWV) in male inhabitants of rural communities in Japan. hCRP and PWV were used as an indexes of atherosclerosis. RESULTS A negative correlation was found between homeostasis model assessment (HOMA) as an index of insulin resistance and adiponectin concentration. Results of stepwise regression analysis for adiponectin showed that age, HOMA and serum triglyceride (TG) were independently correlated with adiponectin. Multiple regression analysis for lipid profile was also performed and revealed that adiponectin and HOMA were independently correlated with TG and serum high density lipoprotein (HDL)-cholesterol but not with serum total cholesterol. A significant negative correlation was found between adiponectin and hCRP in all subjects, and a significant negative correlation between adiponectin and PWV was also found in subjects equal or less than 70 years old. When HOMA was added to this analysis, HOMA was found to be independently correlated with hCRP and PWV, but the adiponectin level did not appear to be a significant predictor of hCRP or PWV. CONCLUSIONS The results suggest that adiponectin plays a role in lipid metabolism and correlates with atherosclerosis either directly or through insulin resistance.