Maternal Coronary Heart Disease, Stroke, and Mortality Within 1, 3, and 5 Years of Delivery Among Women With Hypertensive Disorders of Pregnancy and Pre-Pregnancy Hypertension

Abstract

Background Pre-pregnancy hypertension and hypertensive disorders of pregnancy (HDP; preeclampsia, eclampsia, gestational hypertension) are major health risks for maternal morbidity and mortality. However, it is unknown if racial/ethnic differences exist. We aimed to determine the impact of HDP and pre-pregnancy hypertension on maternal coronary heart disease, stroke, and mortality risk ≤1, 3, and 5 years post-delivery and by race/ethnicity ≤5 years. Methods and Results This retrospective cohort study included women aged 12 to 49 years with a live, singleton birth between 2004 to 2016 (n=254 491 non-Hispanic White; n=137 784 non-Hispanic Black; n=41 155 Hispanic). Birth and death certificates and International Classification of Diseases, Ninth and Tenth Revision, Clinical Modification (ICD-9-CM and ICD-10-CM) diagnosis codes in hospitalization/emergency department visit data defined HDP, pre-pregnancy hypertension, incident coronary heart disease and stroke, and all-cause mortality. During at least 1 pregnancy of the 433 430 women, 2.3% had pre-pregnancy hypertension with superimposed HDP, 15.7% had no pre-pregnancy hypertension with HDP, and 0.4% had pre-pregnancy hypertension without superimposed HDP, whereas 81.6% had neither condition. Maternal deaths from coronary heart disease, stroke, and all causes totaled 2136. Within 5 years of delivery, pre-pregnancy hypertension, and HDP were associated with all-cause mortality (hazard ratio [HR], 2.21; 95% CI, 1.61-3.03), incident coronary heart disease (HR, 3.79; 95% CI, 3.09-4.65), and incident stroke (HR, 3.10; 95% CI, 2.09-4.60). HDP alone was related to all outcomes. Race/ethnic differences were observed for non-Hispanic Black and non-Hispanic White women, respectively, in the associations of pre-pregnancy hypertension and HDP with all-cause mortality within 5 years of delivery (HR, 2.34 [95% CI, 1.58-3.47]; HR, 2.11 [95% CI, 1.23-3.65]; P interaction=0.001). Conclusions Maternal cardiovascular outcomes including mortality were increased ≤5 years post-delivery in HDP, pre-pregnancy hypertension, or pre-pregnancy hypertension with superimposed HDP. The race/ethnic interaction for all-cause mortality ≤5 years of delivery warrants further research.

Keywords: cardiovascular disease; disparities; hypertensive disorders of pregnancy; maternal outcomes; mortality; pre‐pregnancy hypertension; race/ethnicity; stroke.

Figure 1. Flowchart of study inclusion and exclusion criteria.

BMI indicates body mass index; and HDP, hypertensive disorders of pregnancy.

Figure 2. Unadjusted survival since delivery for (A) all‐cause mortality, (B) incident coronary heart disease, and (C) incident stroke for women by hypertensive disorders of pregnancy and pre‐pregnancy hypertension status.

Note: Scale is not a standard survival scale. CHD indicates coronary heart disease; HDP, hypertensive disorders of pregnancy; HTN, hypertension; and pre‐preg, pre‐pregnancy.