Association Between Gestational Diabetes and Postpartum Health Risks

Understanding Gestational Diabetes

Researchers have investigated the connection between a history of gestational diabetes and the likelihood of developing type 2 diabetes and cardiovascular disease after childbirth. Gestational diabetes (GDM) is recognized as a significant risk factor for type 2 diabetes, with a lifetime risk reaching up to 70%. However, the relationship between gestational diabetes and cardiovascular disease remains less explored. Previous studies have indicated an increased risk of cardiovascular events among women with a history of gestational diabetes. Despite this, current guidelines primarily focus on diabetes screening and lifestyle modifications postpartum, without addressing cardiovascular risk factors.

Recent Research Findings

A team of researchers in the United Kingdom published a study in PLOS Medicine that examined the cardiovascular disease risk in women with a history of gestational diabetes. Utilizing a large UK primary care database, the retrospective cohort study compared cardiovascular outcomes between women diagnosed with gestational diabetes and a control group of pregnant women without gestational diabetes, matched by age and pregnancy timeline. The primary outcomes included coronary artery disease and cerebrovascular disease (such as stroke or transient ischemic attack), while the secondary outcomes focused on the incidence of type 2 diabetes and hypertension.

Gestational Diabetes and Heart Disease

After adjusting for various risk factors and potential confounders, the analysis revealed that women with gestational diabetes were over 20 times more likely to develop type 2 diabetes later in life. Additionally, these women faced a twofold increased risk of developing hypertension and a two and a half times greater risk of coronary artery disease. However, no significant increase in risk for cerebrovascular disease was noted. Over the 25-year period examined, from 1990 to 2016, the rates of type 2 diabetes, hypertension, and coronary artery disease remained consistently higher in women with gestational diabetes compared to their counterparts.

Need for Improved Screening

The study also highlighted concerning trends regarding postpartum screening rates for type 2 diabetes and cardiovascular risk factors among women diagnosed with gestational diabetes. Findings indicated that just over half of these women underwent a glycemic measurement in the first year postpartum, with this rate declining to less than 40% in the second and third years following delivery. Alarmingly, a quarter of the women did not receive any glycemic measurement within the first three years. Furthermore, assessments of blood pressure, BMI, and smoking status were conducted in approximately 50% or fewer of the women in the first year postpartum, with similar declines in subsequent years.

Conclusions and Implications

Overall, the results suggest that a history of gestational diabetes not only elevates the risk of type 2 diabetes but also cardiovascular diseases. This finding is consistent with earlier studies indicating a similar association. The research does note limitations, such as incomplete baseline characteristics—including ethnicity and order of pregnancies—which hindered a more comprehensive analysis of factors influencing outcomes. Moreover, the analysis may not have captured all women with gestational diabetes, as only those documented in primary medical records were included, potentially leading to an overestimation of the effect size due to selective documentation of more severe cases.

This study represents the first and largest population-based examination of cardiovascular disease incidence among women with gestational diabetes in the UK. The authors advocate for a reevaluation of current guidelines to incorporate screening recommendations aimed at managing cardiovascular risk factors in this vulnerable population, potentially benefiting from targeted prevention and intervention strategies.

Written by Maggie Leung, PharmD
Reference: Daly, B., Toulis, K. A., Thomas, N., Gokhale, K., Martin, J., Webber, J., . . . Nirantharakumar, K. (2018). Increased risk of ischemic heart disease, hypertension, and type 2 diabetes in women with previous gestational diabetes mellitus, a target group in general practice for preventive interventions: A population-based cohort study. PLOS Medicine, 15(1). doi:10.1371/journal.pmed.1002488