(155) Tight versus standard postpartum blood pressure control: a randomized controlled feasibility trial

Objective:
There are few data about goal postpartum blood pressure (BP) after a hypertensive disorder of pregnancy (HDP). We assessed the feasibility of a pilot RCT and impact of tight versus standard BP control in the first 6 weeks postpartum (PP) in individuals with HDP.

Study Design:

We performed a single-blind feasibility RCT from 11/2023-4/2024 within our institution’s remote BP monitoring program. Participants with HDP and no history of chronic HTN were randomized during the delivery hospitalization to one of two arms for initiation and titration of antihypertensives; (1) tight control aligned with American Heart Association guidelines: inpatient BP ≥140/90 mmHg and/or outpatient ≥135/85 mmHg or (2) standard control: BP ≥150/100 mmHg. Participants underwent study visits at 6 weeks and 6 months PP. The primary outcome was feasibility, defined as the proportion of participants enrolled and retained to 6 months PP. Secondary outcomes included home and study visit BP, use of antihypertensives, unplanned health utilization, and persistent HTN at 6 weeks and 6 months PP.

Results:
Of 143 individuals approached, 61 were randomized (43% enrollment) over a 5-month time course. There was 80% retention to 6 months PP. Compared to standard control, the tight control arm had lower mean/maximum outpatient systolic BP and study visit systolic BP at 6 weeks PP. Compared to standard control, there were lower rates of Stage 2 HTN (BP ≥140/90 mmHg) at 6 months PP in the tight control arm (4.8% vs 28.6%, p=0.03). There were no differences in unplanned health utilization, medication discontinuation due to symptoms, or lactation continuation between arms.

Conclusion:
We show that randomization to tight BP control is feasible in the early PP period and may result in lower rates of Stage 2 HTN at 6 months PP. If confirmed in larger trials, this suggests that the immediate PP period may be a critical time for optimizing BP and supports development of interventions to improve long-term maternal health after HDP.