Hypertensive disorders during pregnancy associated with increased rates of later CVD

Women with hypertensive disorders of pregnancy had increased rates of chronic hypertension, type 2 diabetes, and hypercholesterolemia for years compared to women who were normotensive during pregnancy, a new observational study found.

Researchers identified 58,671 parous participants in the Nurses' Health Study II who did not have cardiovascular disease (CVD) or risk factors of interest at baseline. They followed participants from their first birth through 2013 for self-reported physician diagnosis of chronic hypertension and hypercholesterolemia as well as confirmed type 2 diabetes. Mean follow-up ranged from 25 to 32 years.

Results were published online July 3 by Annals of Internal Medicine.

Compared with women who were normotensive during pregnancy, those with gestational hypertension (2.9%) or preeclampsia (6.3%) during their first pregnancy had higher rates of chronic hypertension (hazard ratios, 2.8 [95% CI, 2.6 to 3.0] and 2.2 [95% CI, 2.1 to 2.3], respectively). They also had increased rates of type 2 diabetes (hazard ratios, 1.7 [95% CI, 1.4 to 1.9] and 1.8 [95% CI, 1.6 to 1.9], respectively) and hypercholesterolemia (hazard ratios, 1.4 [95% CI, 1.3 to 1.5] and 1.3 [95% CI, 1.3 to 1.4], respectively).

Women with gestational hypertension or preeclampsia during their first pregnancy were more likely to develop risk factors for CVD throughout follow-up, although the relative risk for chronic hypertension was strongest within five years after their first birth. Compared to women who were normotensive during pregnancy, those with hypertensive disorders of pregnancy developed CVD risk factors sooner after their first pregnancy and at earlier ages (P<0.001 for both comparisons).

The study authors noted limitations, such as the mostly white cohort and how participants self-reported their diagnoses of hypertensive disorders of pregnancy. Information on confounders was also self-reported, potentially resulting in misclassification or residual confounding, they said.

Women who have hypertensive disorders of pregnancy may benefit from lifestyle interventions and screening to reduce their risk of CVD, the authors concluded.

“Just as guidelines exist to screen for [type 2 diabetes] among women with a history of gestational diabetes, our findings may inform similar guidelines on screening for CVD risk factors among women with a history of [hypertensive disorders of pregnancy],” they wrote.

Although the researchers accounted for prepregnancy risk factors such as body mass index, they were unable to adjust for prepregnancy blood pressure, cholesterol level, or glucose level, an accompanying editorial noted.

“Additional prospective studies with repeatedly measured CVD risk factors in postpartum women are needed to build on the present study findings and to further inform monitoring practices in women with a history of [hypertensive disorders of pregnancy],” the editorialist wrote.