Now, a study of more than 1 million women found that two other common conditions in pregnancy — preeclampsia and gestational hypertension — may double the odds of being diagnosed with diabetes years later.
Lead researcher, Denice Feig, MD, MSc, of the University of Toronto, Canada added that, "Moreover, women who had gestational diabetes plus either preeclampsia or gestational hypertension had a staggering 16- to 18-fold increase in risk of future diabetes."
"The findings suggest that clinicians should screen women with a history of preeclampsia or gestational hypertension on a regular basis," Feig said in an interview.
Additionally, "these patients should take extra precautions to lower diabetes risk, such as exercising regularly and maintaining a healthy weight. Yes, these things should be done anyway, but knowing their risk of diabetes is so high may give women that added push to actually follow through," she said.
The findings emerged from a population-based, retrospective cohort study of 1,010,068 pregnant women who delivered in Ontario, Canada, from April 1994 through March 2008.
Preeclampsia developed in 22,933 of those women, 27,605 had gestational hypertension, and 30,852 had gestational diabetes. Also, 2,100 women had both gestational diabetes and gestational hypertension, and 1,476 women had gestational diabetes and preeclampsia.
The main outcome was new onset diabetes from the time of delivery through March 2011. Overall 35,077 (3.5%) women developed diabetes over a median follow-up of 8.5 years.
Compared with women who did not have any if these conditions, the risk of future diabetes was:
- 1.95 times higher in women with gestational hypertension alone (95% CI 1.83 to 2.07)
- 2.08 times higher in women with preeclampsia alone (95% CI 1.97 to 2.19)
- 12.77 times higher in women with gestational diabetes (95% CI 12.44 to 13.10)
Among women with gestational diabetes and gestational hypertension, the risk jumped to 18.49 times higher (95% CI 17.12 to 19.96), and among those with gestational diabetes and preeclampsia, it was 15.75 times higher (95% CI 14.52 to 17.07).
As for absolute risks, the incidence rates per 1,000 person-years for developing diabetes are:
- 2.81 for women with no gestational diabetes, gestational hypertension or preeclampsia
- 5.26 for gestational hypertension alone
- 6.47 for preeclampsia alone
- 39.77 for gestational diabetes alone
- 55.09 for gestational diabetes and gestational hypertension
- 55.02 for gestational diabetes and preeclampsia.
In an accompanying Perspective article, Thach Tran, MD, of the University of Adelaide in Australia, said: "Based upon this new study, women experiencing hypertensive pregnancy disorders with or without gestational diabetes should be considered as a population at high risk for subsequently developing diabetes.
"All women with a history of hypertensive disorders in pregnancy should thus be counseled about their potential increased risk of subsequent diabetes and the possible opportunity for screening as well as preventive interventions," Tran said.
"These findings highlight a possible risk of developing diabetes in the years following pregnancy, and suggest that clinicians should be aware of the need for preventative measures and vigilant screening for diabetes in women with a history of preeclampsia or gestational hypertension," the researchers wrote.
Tran said that’s especially important because suboptimal screening for postpartum diabetes has been the norm for decades.
"Even in a setting with a high screening rate of 73%, only 27% were screened in accordance with current guidelines," Tran said.
- Note that this retrospective cohort study revealed an association between gestational hypertension and preeclampsia and subsequent diabetes, even in women without gestational diabetes.
- Be aware that the analysis was not adjusted for BMI, which may significantly confound the preeclampsia-diabetes relationship.