Waist circumference is the key risk factor for diabetes in Korean women with history of gestational diabetes

This study investigated relationships between various obesity indices and an onset of type 2 diabetes mellitus (TY2DM) in Korean women with history of gestational diabetes mellitus (GDM). A total of 909 women with history of GDM were enrolled from the four major hospitals, and the first postpartum follow-up examination was made at 6 weeks, and annually thereafter. During postpartum follow-up period, mean 2.13+/-1.75 years, we conducted 2h 75 g OGTT and measured glucose, insulin, c-peptide, lipid profiles, lifestyle and dietary evaluation. For obesity parameters, we measured body weight, body mass index (BMI), waist and hip circumference, subcutaneous fat thickness, body fat percent and weight using bioelectrical impedance tests. Diabetes incidence for 6 years was 12.8% and all the obesity indices were significantly higher in subjects with diabetes or glucose intolerance than those with normal glucose tolerance (p<0.001). When obesity indices were compared between <25th versus >75th percentile, the waist circumference presented with the strongest relationship (odds ratio=5.8, 95% CI 2.8-11.8). This relationship persisted, OR=3.86 (95% CI 1.8-8.2), even after adjusting for the potential confounders. This prospective study revealed that waist circumference is one of the key risk factors for the onset of diabetes in Korean women with history of GDM.