Subtypes and onset of hypertensive disorders of pregnancy and cardiovascular disease within 5 years after delivery.

Background: Hypertensive disorders of pregnancy (HDP) are established predictors of long-term cardiovascular disease (CVD), but the short-term postpartum CVD risk by HDP subtype and onset remains unclear. Materials and methods: We linked electronic health records with vital statistics for 755,606 singleton deliveries in Florida (2012-2017) to examine how different subtypes and onset of HDP are associated with CVD within 5 years postpartum. We classified HDP into six subtypes-chronic hypertension, gestational hypertension, mild preeclampsia, severe preeclampsia, eclampsia, and superimposed preeclampsia - and defined onset as early (<34 weeks) or late (≥34 weeks). Seven CVD outcomes (heart failure, ischemic heart disease, cerebrovascular disease/stroke, arrhythmia/cardiac arrest, cardiomyopathy, peripheral vascular disease, and new-onset chronic hypertension) within five years postpartum were identified. Cox proportional hazards models estimated hazard ratios (HRs) and 95% confidence intervals (CIs) after adjusting for sociodemographic and clinical covariates. Results: Compared with normotensive pregnancies, superimposed preeclampsia carried the highest risks for stroke (HR 3.39; 95% CI 2.93-3.92), arrhythmia (2.62; 2.25-3.07), and peripheral vascular disease (3.09; 2.67-3.57). Eclampsia showed the strongest associations with heart failure (5.23; 3.70-7.39), ischemic heart disease (3.61; 2.65-4.92), and cardiomyopathy (5.25; 3.37-8.18). Severe preeclampsia was most strongly associated with new hypertension (3.27; 3.10-3.46). Early-onset eclampsia and superimposed preeclampsia showed higher CVD risks than their late-onset counterparts, whereas late-onset gestational hypertension and mild preeclampsia were more strongly associated with new hypertension and cardiomyopathy, respectively. Conclusions: HDP subtypes and onset timing impart distinct CVD risk profiles within five years postpartum.