Risk Factors, Trends, and Outcomes Associated with Rural Delivery Hospitalizations Complicated by Hypertensive Disorders of Pregnancy.

Objective: Hypertensive disorders of pregnancy (HDP) may account for a considerable and growing clinical burden at rural hospitals which have been providing fewer obstetric services over the past two decades. The objectives of this analysis were to evaluate trends, risk factors, and outcomes associated with hypertensive disorders of pregnancy (HDP) during delivery hospitalizations at rural hospitals in the United States.

Study Design: The 2000-2020 National Inpatient Sample was used for this repeated-cross sectional analysis. Delivery hospitalizations at rural hospitals to women 15-54 years of age with and without HDP (including preeclampsia and gestational hypertension) were identified. Trends in HDP were characterized with joinpoint regression and estimated as the average annual percent change (AAPC) with 95% CIs. The associations between (i) HDP risk factors and HDP and (ii) HDP and adverse maternal outcomes were estimated with adjusted logistic regression models.

Results: Among 8,885,683 deliveries that occurred at rural hospitals, the proportion with a HDP diagnosis increased significantly from 6.0% in 2000 to 11.1% in 2020 (AAPC 3.1%, 95% CI 2.8%, 3.4%). Preeclampsia with severe features (AAPC 5.5%, 95% CI 4.8%, 6.2%) and superimposed preeclampsia (AAPC 6.5%, 95% CI 5.6%, 7.5%) underwent the largest relative increases over the study period. Obesity, pregestational diabetes, chronic hypertension, multiple gestation, and chronic kidney disease were all associated with increased adjusted odds of HDP. HDP diagnoses were significant associated with severe maternal morbidity (SMM), transfusion, stroke, and disseminated intravascular coagulation. The proportion of overall delivery SMM associated with HDP more than doubled from 11.3% in 2000 to 24.7% of 2020.

Conclusion: Among delivery hospitalizations at rural hospitals, HDP and associated risk factors increased significantly over the study period. Deliveries with HDP accounted for an increasing proportion of population-level SMM. HDP is a major, growing contributor to maternal risk and adverse outcomes during deliveries at rural hospitals.