Obesity index and the risk of diabetes among Chinese women with prior gestational diabetes.

AIMS: There is some confusion regarding which anthropometric measurement of adiposity should be used to indicate diabetes, especially for Asians. The present study was to evaluate different indicators of adiposity (BMI, waist circumference and body fat) with Type 2 diabetes risk among women with prior gestational diabetes mellitus.

METHODS: We performed a cross-sectional survey in 1263 women with gestational diabetes at 1-5 years after delivery. Logistic regression models were used to estimate the association of BMI, waist circumference and body fat with Type 2 diabetes risk.

RESULTS: BMI, waist circumference and body fat were all associated with an increased risk of Type 2 diabetes among women with prior gestational diabetes (all P(trend) < 0.001). After adjustment for waist circumference and body fat, the positive association of BMI with Type 2 diabetes risk became non-significant and reversed. There was a significantly positive association of waist circumference with Type 2 diabetes risk after adjustment for BMI, and a significantly positive association of body fat with Type 2 diabetes risk after adjustment for both BMI and waist circumference. When the joint effects were examined, the significantly positive associations of waist circumference or body fat with Type 2 diabetes risk were consistent among women with different levels of BMI, and the positive association of BMI and Type 2 diabetes risk was significant among women with gestational diabetes with a waist circumference of ≥ 50% or body fat ≥ 50%.

CONCLUSIONS: BMI, waist circumference and body fat were all associated with an increased risk of Type 2 diabetes, and waist circumference and body fat were better indicators than BMI for Type 2 diabetes risk among Chinese women with prior gestational diabetes.