Abstract P3085: Influence of the 5-minute Rest Period on Home Blood Pressure Monitoring in Postpartum Women

Introduction: Home blood pressure (BP) monitoring is a practical approach for out-of-office measurement, allowing confirmation of elevated BP outside of the clinic setting. Patients are instructed to complete a 5-minute seated rest prior to home BP measurements for accuracy; however, compliance with this rest period and its impact on home BP readings remain unknown. Hypothesis: We hypothesize (1) participants would not consistently complete the 5-minute rest prior to home BP measurements, and (2) readings following the 5-minute rest would be significantly lower and have higher consistency within measurements compared to non-compliant readings. Methods: Participants were postpartum women (3 months after delivery; n = 40) enrolled in the multi-site Postpartum 24/7 pilot cohort study. Participants were instructed to assess BP twice on two occasions (morning and night) for 7 days using the Omron 5 series BP monitor, with 5 minutes of quiet, seated rest before the first measurement. A thigh-worn activPAL3 micro was concurrently used to assess compliance with the 5-minute rest. Given 1-minute epoch lengths from the BP monitor data, we defined compliance as readings with at least 4 minutes of continuous sitting from the activPAL3 before the BP reading. The compliance rate was the percentage of compliant measurements. The random and fixed effects of the 5-minute rest and intraclass correlation coefficients (ICC) of BP readings were calculated using a linear mixed model. Results: Participants (mean age: 30.6 ± 4.2 years; mean body mass index: 28.7 ± 6.6 kg/m 2 ) had 1,034 BP readings, with an average of 25.9 of 28 (92.5%) requested readings per person. Of these, 47.2% of BP readings were considered compliant with the 5-minute rest. Systolic BP was significantly lower by -2.83 mmHg (95% CI: -4.21, -1.47) in rest-compliant readings compared to non-compliant readings, though diastolic BP was similar. ICCs for rest-compliant systolic and diastolic BP readings were 0.708 and 0.690, respectively, suggesting moderate consistency; the corresponding ICCs for non-compliant readings were lower at 0.598 for systolic and 0.581 for diastolic BP. Conclusions: Participants were able to complete most home BP readings but with low compliance with the 5-minute rest period, which affected systolic BP values and overall BP consistency. Future research should assess rest compliance rates in more general populations and its impact on clinical decision-making and outcomes.