Self-Monitoring BP Did Not Improve Control for Pregnant Patients with Hypertension

Compared with usual care, blood pressure self-monitoring with telemonitoring did not have significant improvements in clinic-based blood pressure control in a cohort of pregnant individuals with chronic or gestational hypertension, according to new findings.

Investigators found no significant difference in mean systolic blood pressure among those allocated to self-monitoring of blood pressure (SMBP).

“These results were similar for all subgroups including those with gestational hypertension, whether they were recruited directly into the trial or transitioned from the linked trial when they developed hypertension,” wrote lead investigator Lucy C. Chappell, MB BChir, PhD, Department of Women and Children’s Health, St Thomas’ Hospital.

The Blood Pressure Monitoring in High Risk Pregnancy to Improve the Detection and Monitoring of Hypertension 2 (BUMP 2) trial evaluated the effect of SMBP in individuals with pregnant hypertension on BP control. Alongside the trial, a linked trial assessed self-monitoring for the detection of elevated BP in individuals with higher-risk pregnancies, according to investigators.

The study population consisted of individuals aged ≥18 years with chronic hypertension who were enrolled up to 37 weeks’ gestation, or gestational hypertension enrolled at 20 to 37 weeks’ gestation. They were recruited from 15 hospital maternity units in the United Kingdom.

These individuals were randomized 1:1 to either SMBP or usual care. Those randomized to SMBP were given a monitor validated in pregnancy and preeclampsia and a secure telemonitoring system using an app, while usual care consisted of blood pressure measured by professionals at regular antenatal clinics.

Chappell and colleagues identified the primary outcome as the difference in mean systolic BP recorded by health care professionals between randomization and birth. A total of 850 pregnant individuals with hypertension were randomized between November 2018 and September 2019. The primary outcome was available for 416 participants (96.7%) in the SMBP group and 405 participants (96.4%) in the usual care group.

Those with chronic hypertension were recruited at 20 weeks and had a mean age of 36 years, while those with gestational hypertension were recruited at 33 weeks and had a mean age of 34 years.

In the cohort of individuals with chronic hypertension, the mean clinic systolic BP was 133.8 Hg in the SMBP group compared with 133.6 mm Hg in the usual care group (adjusted mean difference, 0.03 mm Hg [95% CI, -1.73 to 1.79]).

Further, in the gestational hypertension cohort, the mean systolic BP was 137.6 mm Hg in the SMBP group compared with 137.2 mm Hg in the usual care group (adjusted mean difference, -0.03 mm Hg [95% CI, -2.29 to 2.24]).

Investigators additionally observed no significant differences in adverse events or serious adverse events between the self-monitoring and usual care allocations (serious adverse events: 4 vs 2 in the chronic hypertension group and 4 vs 1 in the gestational hypertension group).

The study, “Effect of Self-monitoring of Blood Pressure on Blood Pressure Control in Pregnant Individuals with Chronic or Gestational Hypertension,” was published in JAMA.