Abstract P424: Postpartum Blood Pressure Trajectories After Hypertensive Disorders Of Pregnancy

Abstract

Background: Following a hypertensive disorder during pregnancy, blood pressure (BP) generally decreases rapidly in the first three weeks postpartum followed by a period of stabilization. Little is known about patterns of deviation from this trend. Methods: Patients with hypertension during pregnancy (chronic, gestational, or during delivery hospitalization) were enrolled in a remote BP monitoring program and provided with a cell-enabled cuff to take daily BP measurements during their first six weeks postpartum. Measurements were transmitted to a portal and integrated with their electronic medical record. Patients delivering between January 2021 and December 2022 with ≥2 BP measures at an urban safety net hospital were included (n=1,571). Quadratic group-based trajectory models were used to identify latent patterns of postpartum systolic BP (SBP) and diastolic BP (DBP) over time, a method that can be used to capture clinically distinct sub-groups of patients. Patients were grouped into one of four trajectories based on posterior probabilities. Demographic and reproductive characteristics of each trajectory group were examined. Results: Based on 1,571 patients with an average of 15 postpartum BP measurements per patient, the group trajectory model identified 4 trajectories of SBP and DBP (labeled as starting BP value-rate of BP decline): (1) low-steep (SBP 123, DBP 78), (2) moderate-steep (SBP 134, DBP 87), (3) high-gradual (SBP 143, DBP 93), and (4) high-flat (SBP 146, DBP 95). The percent of patients falling into each SBP trajectory group were (1)22.6 (n=346), (2)38.0 (n=611), (3)28.6 (n=451), (4)10.8 (n=163), and for DBP were (1)18.2 (n=288), (2)35.4 (n=557), (3)31.9 (n=508), and (4)14.4 (n=218). Key demographic and pregnancy characteristics varied across SBP and DBP trajectory groups. The high-flat groups were most likely to be older (≥36 years) and non-Hispanic Black. The high-flat SBP and DBP groups had the highest percentage of preterm births (26.4%, 43 out of 163; 20.6%, 45 out of 218, respectively). Conclusion: In this on-going observational study, we characterized 4 distinct group trajectories of SBP and DBP in the 6-weeks postpartum. These data may aid in the identification of patients at risk of persistent postpartum hypertension.