(1048) Blood pressure thresholds associated with postpartum preeclampsia readmissions

With the recent publication of the CHAP Trial and revised recommendations for the treatment threshold of chronic hypertension (HTN) during pregnancy, we aimed to evaluate blood pressure (BP) thresholds associated with postpartum readmission for HTN.

Study Design:

In this retrospective cohort study, we evaluated all postpartum readmissions within 42 days of discharge from January 2018 through May 2022. Sociodemographic, delivery, and readmission data were collected.

Results:

23,374 deliveries occurred at our quaternary hospital during the study period. There were 489 readmissions, 248 of which (51%) were due to postpartum HTN. Of patients readmitted for hypertension, 101 (41%) had a prior diagnosis of a hypertensive disorder (i.e. gestational HTN, preeclampsia, HELLP, chronic HTN) prior to initial discharge (Group 1), 147 (59%) had no prior diagnosis (Group 2). Baseline demographics are summarized in Table 1. Compared to those without an existing diagnosis, patients with hypertensive disorders prior to initial discharge were more likely to be readmitted within 3 days of initial discharge (Odds Ratio (OR) 2.08 95% Confidence interval (CI) 1.22-3.53). Patients with an existing diagnosis were more likely to have abnormal blood pressure 24 hours prior to initial discharge (OR 4.42 95% CI 2.34-8.49). Among those without a prior diagnosis, 33.6% had blood pressures of either systolic BP ≥ 140 or diastolic BP ≥ 90, and 61.9% had blood pressure of either systolic between 130-140 or diastolic between 80-90 within 24 hours prior to initial discharge. Of all patients with abnormal vital signs prior to initial discharge, 13.7% received a new antihypertensive prescription.

Conclusion:

In the current study the majority of readmitted patients regardless of prior diagnosis of HTN had elevated BP prior to initial discharge. Those with BP in the 130-140/80-90 range may benefit from closer surveillance in the postpartum period. Further research to evaluate the benefit of antihypertensive initiation in patients with mild range BP in the postpartum period are needed.