Air pollution exposures and adverse childhood experiences in relation to sleep health in middle childhood

Purpose/aims: Sleep health is an understudied but potentially important outcome of joint air pollution and psychosocial stress exposures in children. This study examined children's sleep health outcomes in relation to air pollution (PM_2.5, NO₂, O₃; aim 1), adverse childhood experiences (ACEs; aim 2), and air-pollution-by-ACEs interactions (aim 3). Methods: Participants were from ECHO-PATHWAYS, a three-cohort consortium. Aim 1 included 1166 participants across the three cohorts, and aims 2 and 3 included a subset of 719 participants from a single cohort. PM_2.5 (μg/m³), NO₂ (ppb), and O₃ (ppb) were estimated during early infancy (0–6 months) and early childhood (6 months–6 years) using geocoded residential histories and spatiotemporal prediction models. Children's lifetime exposures to 8 different types of ACEs were measured via parent report at child age 8–9 years. Sleep disturbance and sleep-related impairment outcomes were measured via children's self-report at age 8–9 years. Analyses included linear regressions, adjusting for a priori-selected confounders. Results: Aim 1 results showed that, for every 1 IQR increase in early infancy NO₂, children scored 0.31 (95 % CI 0.01, 0.61) points lower on sleep-related impairment. Aim 3 results showed that, for every additional ACE, the difference in sleep-related impairment per IQR increase in early infancy and early childhood NO₂ was 0.43 (95 % CI 0.08, 0.78) and 0.41 (95 % CI 0.08, 0.73), respectively (ps_interactions = 0.02). No other associations were observed. Conclusion: We found little evidence of associations, with the exception of suggestive evidence for associations of NO₂ and NO₂-by-ACE interactions with sleep-related impairment.