Protocol and Characteristics of the Basel Postpartum Hypertension Cohort (Basel-PPHT-Cohort): an Interim Analysis

Abstract

Introduction: Postpartum hypertension (PPHT) is hypertension that persists or develops directly after pregnancy. PPHT affects 10% of pregnancies and is the most common cause for re-hospitalization after giving birth. In general, PPHT stems from hypertensive disorders of pregnancy (HDP). The aim of the current interim report of the Basel PPHT registry is to describe the cohort, and to determine feasibility and acceptance of a home-based telemonitoring management strategy (HBTMS) in women with PPHT. Methods: Enrollment in the cohort began in June 2020 during the SARS-CoV-2 pandemic at the University Hospital Basel. Women in the maternity ward were screened for preexisting hypertension, HDP, and de novo postpartum hypertension and after consenting, were enrolled. In this pragmatic non-randomized prospective trial, women in the PPHT cohort could choose, between a HBTMS or usual care which consisted of in-hospital appointments at the hypertension clinic. HBTMS was defined as a smartphone application or a programmed spreadsheet to report blood pressure followed by telephone consultations. Standard of care was hospital-based visits as clinically needed after discharge. All participants were assessed three months after delivery with a standardized clinical visit including a 24-hour blood pressure measurement, blood, biomarker, and urine analysis. Results: 311 participants were enrolled from 06/20-08/23. Mean age was 34±5.3 years. Regarding pregnancy-related medical history: 10 % had preexisting hypertension, 27.3 % gestational hypertension, 53% preeclampsia (PE), 0.3% eclampsia, 6% HELLP (Hemolysis, Elevated Liver enzymes and Low Platelets) and 18.3% had de novo PPHT. More than one diagnosis was possible. Family history of cardiovascular disease was seen in 49.5%, 7.5% had a family history of PE. 23.3% were determined as high risk for PE during pregnancy. The most common type of delivery was C-Section (68.5%), mean hospital stay was 6.3 days (±3.9) and IUGR (intrauterine growth restriction) was seen in 21% of the newborns. 99% of participants chose a home-based management strategy. Conclusion: This first description of the Basel PPHT Cohort showed that a HBTMS is well accepted. This is particularly relevant in the direct postpartum period and even more pertinent when the exposure of hospital visits should be avoided when possible.