Preeclampsia-Associated Cardiovascular Risk Factors 6 Months and 2 Years After Pregnancy: The P4 Study

Abstract

Background: Increased cardiovascular risk following preeclampsia is well established and there are signs of early cardiovascular aging 6 months postpartum. This study assessed whether blood pressure (BP) and other cardiovascular measures are abnormal 2 years postpartum in the same cohort to determine ongoing risk markers.

Methods: Six months and 2 years postpartum, BP was measured using sphygmomanometry, 24-hour ambulatory BP monitoring, and noninvasive central BP. Anthropometric measures, blood, and urine biochemistry were performed. Cross-sectional comparisons between preeclampsia and normotensive pregnancy (NP) groups and longitudinal comparisons within each group were made at 6 months and 2 years.

Results: Two years postpartum, 129 NP, and 52 preeclampsia women were studied who also had 6 months measures. At both time points, preeclampsia group had significantly higher BP (office BP 2 years, 112±12/72±8 versus 104±9/67±7 mm Hg NP; [P<0.001]; mean ambulatory BP monitoring 116±9/73±8 versus 106±8/67±6 mm Hg NP; [P<0.001]). No significant BP changes noted 6 months to 2 years within either group. Office BP thresholds of 140 mm Hg systolic and 90 mm Hg diastolic classified 2% preeclampsia and 0% NP at 2 years. American Heart Association 2017 criteria (above normal, >120/80 mm Hg) classified 25% versus 8% (P<0.002), as did our reference range threshold of 122/79 mm Hg. American Heart Association criteria classified 60% post-preeclampsia versus 16% after NP with above-normal ambulatory BP monitoring (P<0.001). Other cardiovascular risk markers more common 2 years post-preeclampsia included higher body mass index (median 26.6 versus 23.1, P=0.003) and insulin resistance.

Conclusions: After preeclampsia, women have significantly higher BP 6 months and 2 years postpartum, and have higher body mass index and insulin-resistance scores, increasing their future cardiovascular risk. Regular cardiovascular risk screening should be implemented for all who have experienced preeclampsia.

Keywords: cardiovascular diseases; hypertension; longitudinal studies; postpartum period; pre-eclampsia; risk factors.

Figure 1.

Participant flow P4 Study (Postpartum Physiology, Psychology, and Pediatric). 2Y indicates 2 years; 3M, <3 months; 6M, 6 months; DNA, did not attend; NP, normotensive pregnancy; PE, preeclampsia; and PP, postpartum. #At P4 commencement, only questionnaires were administered at 2Y; when funding became available 2Y visits and blood tests instituted. ##Includes participants unable to attend due to work demands, those interstate or overseas, and those who did not attend appointment.

Figure 2.

Longitudinal postpartum office and ambulatory blood pressure (ABPM) readings. A, Office and ambulatory blood pressure 6-month (6M) and 2 years (2Y) post-preeclampsia. B, Office and ambulatory blood pressure 6M and 2Y after normotensive pregnancy. Y axis denotes mmHg (average). DBP indicates diastolic blood pressure; and SBP, systolic blood pressure.