Plasma adiponectin concentrations are associated with dietary glycemic index in Malaysian patients with type 2 diabetes

Adiponectin, an adipocyte-derived hormone has been implicated in the control of blood glucose and chronic inflammation in type 2 diabetes. However, limited studies have evaluated dietary factors on plasma adiponectin levels, especially among type 2 diabetic patients in Malaysia. The aim of this study was to investigate the influence of dietary glycemic index on plasma adiponectin concentrations in patients with type 2 diabetes. A cross-sectional study was conducted in 305 type 2 diabetic patients aged 19-75 years from the Penang General Hospital, Malaysia. Socio-demographic information was collected using a standard questionnaire while dietary details were determined by using a pre-validated semi-quantitative food frequency questionnaire. Anthropometry measurement included weight, height, BMI and waist circumference. Plasma adiponectin concentrations were measured using a commercial ELISA kit. Data were analyzed using multiple linear regression. After multivariate adjustment, dietary glycemic index was inversely associated with plasma adiponectin concentrations (beta =-0.272, 95% CI -0.262, -0.094; p<0.001). It was found that in individuals who consumed 1 unit of foods containing high dietary glycemic index that plasma adiponectin level reduced by 0.3 mu g/mL. Thirty two percent (31.9%) of the variation in adiponectin concentrations was explained by age, sex, race, smoking status, BMI, waist circumference, HDL-C, triglycerides, magnesium, fiber and dietary glycemic index according to the multiple linear regression model (R-2=0.319). These results support the hypothesis that dietary glycemic index influences plasma adiponectin concentrations in patients with type 2 diabetes. Controlled clinical trials are required to confirm our findings and to elucidate the underlying mechanism.