Abstract
Introduction: Hypertensive disorders of pregnancy (HDP) such as gestational hypertension, preeclampsia and eclampsia lead to increased maternal morbidity, mortality, and are associated with cardiovascular disease risk. It remains unknown whether HDP is a result of pathological events associated with pregnancy complications and/or due to pre-existing cardiovascular traits of the mother unmasked by the stressful nature of pregnancy.
Objective: To determine whether cardiovascular health prior to pregnancy, assessed by the American Heart Association's Life's Essential 8 (LE8) score, is associated with risk of HDP.
Methods: CARDIA is a prospective cohort study of 5,115 Black or White US adults aged 18-30 at baseline (1985-86), from four US cities, followed over 30 years across nine study visits. Participants underwent assessments of health behaviors (diet, smoking, physical activity, sleep) and clinical metrics (body mass index, blood pressure, cholesterol, fasting glucose, medication use) used to estimate the LE8 score (range: 0 to 100). Cardiovascular health was categorized as low (LE8 <50), moderate (LE8 50-79) or high (LE8 ≥80). HDP was self-reported as having a post-baseline pregnancy lasting ≥20 weeks gestation complicated by gestational hypertension, preeclampsia or eclampsia. We used generalized mixed models to determine the association between time-updated LE8 and incident HDP accounting for the 2,036 live births nested within 1,227 women. Models were adjusted for baseline education and income, time-updated age and parity, follow-up time, and cumulative live births. Missing values for LE8 computation at an exam were imputed from the most proximal available value.
Results: Mean (SD) baseline age was 24.1 years (3.6), 48.7% were Black women; 19.9% reported HDP in ≥1 pregnancy post-baseline. At baseline, the average LE8 score was 79.0 (11.0) and significantly lower among women who developed HDP (77.0 [10.9]) than in women who did not (79.5 [11.0]), p<0.01. From fully adjusted mixed models, compared to women with high pre-pregnancy cardiovascular health, women with moderate (OR: 1.79, 95%CI: 1.14, 2.81) and low cardiovascular health (OR: 4.03, 95%CI: 1.09, 14.95) prior to pregnancy had greater odds of HDP.
Conclusions: Women with low or moderate cardiovascular health were at greater risk of developing HDP compared to women with high cardiovascular health. Results suggest that lower pre-pregnancy cardiovascular health is an independent risk factor for HDP.