Remote Monitoring Compared With In-Office Surveillance of Blood Pressure in Patients With Pregnancy-Related Hypertension: A Randomized Controlled Trial

Abstract

Objective: To compare the rate of blood pressure ascertainment within 10 days of postpartum discharge among individuals with hypertensive disorders of pregnancy randomized either to in-office blood pressure assessment or at-home monitoring.

Methods: This was a multisite randomized controlled trial of postpartum patients diagnosed with a hypertensive disorder of pregnancy before discharge between April 2021 and September 2021 and was performed at two academic training institutions. Patients were randomized to either an in-office blood pressure check or remote monitoring through a web-enabled smartphone platform. The primary outcome was the rate of any blood pressure ascertainment within 10 days of discharge. Secondary outcomes include rates of initiation of antihypertensive medication, readmission, and additional office or triage visits for hypertension. Assuming a 10-day postdischarge blood pressure ascertainment rate of 50% in the in-office arm, we estimated that 186 participants would provide 80% power to detect a 20% difference in the primary outcome between groups.

Results: One hundred ninety-seven patients were randomized (96 remote, 101 in-office). Patients with remote monitoring had higher rates of postpartum blood pressure ascertainment compared with in-office surveillance (91.7% [n=88] vs 58.4% [n=59]; P<.001). There were 11 (11.5%) patients in the intervention arm whose only qualifying blood pressure was a postdischarge in-person ascertainment, yielding a true remote monitoring uptake rate of 80.2%. In those with remote blood pressure uptake (n=77), the median number of blood pressure checks was 15 (interquartile range 6-26) and the median duration of remote monitoring use was 14 days (interquartile range 9-16). There were no differences in rates of readmission for hypertension (5.0% [n=5] vs 4.2% [n=4], P=.792) or initiation of antihypertensive medications after discharge (9.4% [n=9] vs 6.9% [n=7], P=.530). Rates of unscheduled visits were increased in the remote monitoring arm, but this did not reach statistical significance (5.0% [n=5] vs 12.5% [n=12], P=.059). When stratifying the primary outcome by race and randomization group, Black patients had lower rates of blood pressure ascertainment than White patients when assigned to in-office surveillance (41.2% [n=14] vs 69.5% [n=41], P=.007), but there was no difference in the remote management group (92.9% [n=26] vs 92.9% [n=52], P>.99).

Conclusion: Remote monitoring can increase postpartum blood pressure ascertainment within 10 days of discharge for women with hypertensive disorders of pregnancy and has the potential to promote health equity.