Differences in engagement and outcomes in a postpartum hypertension monitoring program by infant NICU admission

Remote postpartum self-measured blood pressure (SMBP) monitoring programs improve rates of recommended BP ascertainment among individuals with hypertensive disorders of pregnancy (HDP) overall. Healthcare utilization patterns differ among individuals whose infants are admitted to the neonatal intensive care unit (NICU) and those with infants in the standard newborn nursery, but it is unclear whether this difference translates into a reduction of SMBP program engagement.

Our SMBP program is offered to all postpartum individuals with HDP at our hospital. Participants were stratified by those with infants admitted to the NICU or to the newborn nursery. The primary outcome was SMBP engagement, defined as reporting ≥1 BP measurement between hospital discharge and 10 days postpartum. Secondary outcomes included the total number of SMBP measurements during the 6-week program, hypertension (HTN)-related Emergency Department (ED) visit or readmission, initiation of antihypertensive medication, and severe maternal morbidity (SMM), as defined by HTN-related conditions within the CDC SMM composite. Relative risks (RRs) were calculated after adjusting for differences between study groups identified in bivariate analyses.

Among 2556 SMBP participants, 28% (n = 707) had infants admitted to the NICU. Compared to those with infants in the newborn nursery, those with infants in the NICU delivered at earlier gestational ages, were more likely to have severe preeclampsia and superimposed preeclampsia, and had higher rates of postpartum ICU admission. After adjusting for these factors, there was no significant difference in SMBP engagement (adjusted RR [aRR], 0.99; 95% confidence interval [CI], 0.89-1.10). There were no significant differences in secondary outcomes including HTN-related ED visits, readmissions, or SMM.

The rate of SMBP engagement was similar regardless of NICU admission and lower than has been reported in other studies. However, despite having more severe types of HDP, NICU parents had rates of postpartum HTN-related ED visits or readmissions similar to those with infants in the newborn nursery. Collectively, these findings suggest that while remote SMBP programs may not effectively encourage adherence to recommended BP ascertainment, participation may mitigate postpartum HTN-related morbidity in this population.