Background: Preeclampsia (PE) increases maternal risk of hypertension and cardiovascular disease from within 10 years of the index pregnancy. However, women at increased cardiovascular risk may go undetected because data on normal blood pressure (BP) and other cardiovascular risk indices in the first 5 years postpartum is lacking. This study aims to report BP and indices of cardiovascular health in women 2 years after normotensive pregnancy (NP) versus PE, and compare these to measures from the same women at 6 months postpartum.
Methods: Prospective cohort with paired measures of 114 NP and 51 PE pregnancies 6 months and 2 years postpartum. Measures included manual, central and 24-hour ambulatory BP, radial artery applanation tonometry, HOMA-IR score, albumin-creatinine ratio (ACR), and echocardiography in a subgroup. Provisional reference intervals for normal BP at 2 years postpartum were derived from the NP group. Groups were compared using usual quantitative methods. Paired testing was used to compare 6-month and 2-year data.
Results: At 2 years postpartum, PE had significantly higher manual (111±12/72±8mmHg vs. 103±10/66±7mmHg), central (103±12/75±9mmHg vs. 96±10/68±7mmHg) and 24-hour average BP (116±9/73±8mmHg vs. 106±8/67±6mmHg) compared to NP (all p<0.001). There was no difference between 6 months and 2 years postpartum within each group. Two percent of PE were hypertensive at 2 years using the traditional reference range of ≥140/90mmHg for manual BP; compared to 19.6% when utilising the novel reference interval derived from the NP group. There was no difference between groups in HOMA-IR score, ACR or echocardiographic parameters at 2 years postpartum.
Conclusion: PE had higher BP at 2 years postpartum compared to NP, predicted by the 6 months findings. Utilising a normal range derived from the NP group detected hypertension in a greater proportion of PE women than traditional reference ranges, which may have implications for risk stratification in high-risk women.