Optimal physical activity timing and 24-hour activity composition for prevention of hypertensive disorders of pregnancy

/ABSTRACT De novo hypertensive disorders of pregnancy (HDP), including gestational hypertension and preeclampsia/eclampsia, impact 10-15% of pregnancies and are considered salient risk factors for future cardiovascular disease (CVD) in women. Moderate-to-vigorous physical activity (PA) is strongly recommended for CVD prevention; however, there is currently limited evidence on the importance of PA timing (early vs. mid- pregnancy and change across pregnancy) for HDP prevention. In addition, light-intensity PA has been linked to better cardiovascular risk profiles in the general adult population, but few studies have investigated associations of light-intensity PA during pregnancy with HDP, when light-intensity PA may be a more achievable behavior and associations may differ due to pregnancy-associated cardiovascular changes. Finally, previous research in the general adult population suggests the composition of the entire 24-hour day—which includes sleep and sedentary behavior in addition to PA—impacts CVD risk and mortality; however, the optimal 24-hour activity composition for reducing risk of HDP remains unclear as few studies have considered more than one behavior simultaneously. As behaviors are not independent within the context of the 24-hour day, applying a 24-hour activity paradigm, including sleep, sedentary behavior, light-intensity PA, and moderate-to- vigorous-intensity PA, is important for understanding these relationships. Identifying beneficial lifestyle-related behaviors and combinations of these behaviors to reduce risk of HDP is of critical importance to inform the development of clinical and public health guidelines and to promote lifestyle strategies to reduce CVD risk in women. To address this critical gap, the proposed study will explore PA timing and intensity and optimal 24- hour activity compositions at multiple pregnancy timepoints for reducing HDP risk. We will leverage Kaiser Permanente Northern California’s diverse population of pregnant persons and extensive electronic health record database, along with innovative 24-hour accelerometry, to conduct a longitudinal cohort study of 1,050 pregnant individuals with follow-up from early pregnancy through delivery. In early and mid-pregnancy, we will collect device-measured 24-hour activity creating a large cohort with measurement of multiple aspects of PA and sleep across pregnancy linked to de novo HDP identified by validated algorithms in the electronic health record to determine prospective associations of PA in pregnancy by timing and intensity (Aim 1) and identify optimal 24-hour activity compositions (Aim 2) with risk of HDP, and explore mediators and moderators of these associations (Exploratory Aim). Results will elucidate the relationships between PA timing and intensities, and optimal 24-hour activity paradigm, and risk of HDP. These findings will be paramount for guiding future PA and 24-hour activity guidelines for pregnancy and clinical trials of lifestyle interventions promoting healthy PA and 24-hour activity in pregnancy, which have the potential to improve long-term maternal cardiovascular health and reduce the high morbidity and mortality from CVD in women. Project Number: 1R01HL176879-01A1 | Fiscal Year: 2025 | NIH Institute/Center: National Heart Lung and Blood Institute (NHLBI) | Principal Investigator: Sylvia Badon | Institution: KAISER FOUNDATION RESEARCH INSTITUTE, Oakland, CA | Award Amount: $751,124 | Activity Code: R01 | Study Section: Reproductive, Perinatal and Pediatric Health Study Section[RPPH] View on NIH RePORTER: https://reporter.nih.gov/project-details/1R01HL17687901A1