Moderately elevated blood pressure during pregnancy and odds of hypertension later in life: the POUCHmoms longitudinal study

Objective Hypertensive disorders in pregnancy signal an increased risk of cardiovascular disease for women. However, future hypertension risk among pregnant women with moderately elevated blood pressure (BP) is unknown. We examined associations among moderately elevated BP or hypertensive disorders during pregnancy and later prehypertension or hypertension. Design Longitudinal cohort study. Setting Five communities in Michigan, USA. Sample Data are from pregnant women enrolled in the Pregnancy Outcomes and Community Health Study. We included 667 women with gestational BP measurements who participated in the POUCHmoms Study follow-up 7-15 years later. Methods Moderately elevated BP was defined as two measures of systolic BP >= 120 mmHg or diastolic BP >= 80 mmHg among women without a hypertensive disorder. Weighted multinomial logistic regression models estimated odds of prehypertension or hypertension at follow-up, adjusted for maternal confounders and time to follow-up. Main outcome measures Prehypertension or hypertension. Results Women meeting the moderately elevated BP criteria (64%) had significantly higher odds of hypertension at follow-up (adjusted odds ratio 2.6; 95% confidence interval 1.2-5.5). These increased odds were observed for moderately elevated BP first identified before or after 20 weeks of gestation, and for elevated systolic BP alone or combined with elevated diastolic BP. Conclusions Moderately elevated BP in pregnancy may be a risk factor for future hypertension. Pregnancy offers an opportunity to identify women at risk for hypertension who may not have been identified otherwise.