β-cell dysfunction in women with previous gestational diabetes is associated with visceral adipose tissue distribution

CONTEXT: Glucose intolerance in pregnancy predicts an increased risk of future type 2 diabetes. OBJECTIVE: The aim of the study was to evaluate glucose metabolism in women with and without gestational diabetes mellitus (GDM) at 5 years follow-up and identify risk factors associated with disturbed glucose metabolism post-partum. DESIGN: This follow-up study included 300 consecutively enrolled women from a previous population-based cohort study. The participants underwent oral glucose tolerance test under pregnancy and in the follow-up study, in addition to dual-energy X-ray absorptiometry in the follow-up study. RESULTS: Fifty-two women (17.7%) were found to have GDM in pregnancy with an odds ratio of 4.8 developing prediabetes 5 years later. β-cell function, but not insulin resistance or sensitivity, was reduced in the follow-up study after adjusting for known risk factors. Furthermore, visceral fat content at follow-up was increased in GDM women compared to non-GDM women, and the β-cell function declined with increasing visceral fat in both groups but was more pronounced in the women with previous GDM. CONCLUSIONS: Women with GDM are at increased risk of developing prediabetes and have a decreased β-cell function 5 years post-partum that is associated with increased visceral fat mass.