Objectives Hypertensive disorders of pregnancy (HDP) are primary antecedents of maternal cardiovascular morbidity during and after pregnancy. Despite evidence that 24-hour movement behaviours, including moderate-to-vigorous and light-intensity physical activity (MVPA, LPA), sedentary behaviour (SED) and sleep, relate to cardiovascular disease risk, associations with HDP are unknown. This study identified optimal 24-hour behavioural compositions across pregnancy associated with lower HDP risk. Methods The Pregnancy 24/7 cohort study (N=500) quantified 24-hour movement behaviours in each trimester (10 0 –12 6 , 20 0 –22 6 and 32 0 –34 6 weeks gestation) and examined associations with HDP. Participants were enrolled between 2021–2024 from three US study sites. Movement behaviours were quantified from 7-day × 24-hour monitor wear using the activPAL3 micro (MVPA, LPA and SED) and Actiwatch Spectrum Plus (sleep). HDP (gestational hypertension and pre-eclampsia) was abstracted from medical records. Compositional binomial regression models predicted HDP risk based on isometric log-ratio transformation of 24-hour movement behaviours. Optimal overlapping behavioural compositions were identified by aggregating up to three repeated assessments of 24-hour data. Results Among 470 participants with complete data, 86 (18.3%) developed HDP. The optimal overlapping daily composition (0–5th percentile) associated with the lowest HDP risk (7.2%) consisted of 5.9 (5.5–6.6) hours SED, 7.9 (6.4–8.9) hours LPA, 7 (2–22) minutes MVPA and 10.1 (8.5–11.3) hours sleep. Risk increased exponentially among participants with more than 10 hours/day of SED or less than 5 hours/day of LPA. Conclusion SED and LPA were the strongest modifiable predictors of HDP, independent of trimester. These findings inform behavioural intervention targets to reduce the risk of HDP.
Whitaker et al. (Wed,) studied this question.