Gestational diabetes confers long-term type 2 diabetes risk

The long-term risk of type 2 diabetes or impaired glucose tolerance is common in women with gestational diabetes, reports a new China study.

Researchers conducted a prospective nested case-cohort study including 121 women (mean age, 50.3 years) who were followed for a mean of 22.5 years. Oral glucose tolerance tests were conducted at 8, 15 and 22 years.

Twenty participants (16.9 percent) were identified to have type 2 diabetes over the follow-up period, with half being newly diagnosed. Forty-four had either diabetes or abnormal glucose tolerance, and 24 (20.3 percent) had metabolic syndrome.

Multiple logistic regression analysis revealed that a history of gestational diabetes mellitus or gestational impaired glucose tolerance (GDM/GIGT) significantly increased the risk of type 2 diabetes or abnormal glucose tolerance at follow-up, even after adjusting for potential confounders (odds ratio [OR], 2.78, 95 percent confidence interval [CI], 1.18–6.55; p=0.02).

Longitudinal assessment was possible in 943 women. At the 8-year follow-up, 40.3 percent of the GDM/GIGT participants were dysglycaemic, as opposed to only 17.7 percent of those with normal glucose tolerance (p=0.001). This gap remained significant even after 22 years of follow-up (52.6 percent vs 30.0 percent; p=0.025). Two-hour glucose levels were similarly longitudinally elevated in GDM/GIGT participants.

“There is a need to raise awareness concerning this at-risk population and to implement active surveillance to prevent associated morbidity and mortality,” said researchers.