Perinatal & Pediatric
Examining Sleep Problems as a Mediator Linking Prenatal Phthalate Exposure to Executive Function in Middle Childhood Joana Amankwaa* Joana Amankwaa Amankwaa Amankwaa Utah State University
Prenatal phthalate exposure has been linked to poorer executive function (EF) skills in children. However, mechanisms underlying these associations remain unclear. Sleep is a biologically plausible pathway as evidence suggests that phthalates may disrupt hormonal systems involved in sleep regulation which could contribute to sleep disruption and, in turn, poorer EF. Using data from the Mount Sinai Children’s Environmental Health Study, we examined whether child sleep mediates the relationship between prenatal phthalate exposure and EF in middle childhood.
This sample includes 404 mother–child dyads with the analytic sample including 87 children with complete data on phthalate exposure, sleep, and EF. Prenatal exposure was assessed using maternal spot urine samples collected between 25 and 40 weeks’ gestation and composite log scores were created for low molecular weight (LMW) and high molecular weight (HMW) phthalates. Child sleep at age 4 was assessed using caregiver-reported Pediatric Sleep Questionnaire items. EF was measured between ages 6-9 using the Behavior Rating Inventory of Executive Function (BRIEF). For children with EF data at multiple waves, the oldest available BRIEF assessment was used, resulting in a single EF score per child. Analyses controlled for creatinine, race, sex, marital status, gestational age, smoking during pregnancy, education, and bedroom sharing.
Across separate LMW and HMW models, prenatal phthalate exposures were not associated with sleep duration (LMW ß = 0.01, 95% CI [−0.17, 0.18]; HMW ß = 0.03, 95% CI [−0.16, 0.21]) or daytime sleepiness (LMW ß = 0.01, 95% CI [−0.04, 0.05]; HMW ß = −0.02, 95% CI [−0.06, 0.02]). Only daytime sleepiness was associated with poorer EF in the LMW and HMW models (β = 9.60, 95% CI [2.93, 16.46] and β = 9.40, 95% CI [2.72, 16.40], respectively). Finally, no significant indirect effects were found.
Overall, prenatal phthalate exposure was not associated with child sleep problems, and sleep problems did not mediate associations between phthalates and EF. However, the association of daytime sleepiness with poorer EF underscores a potentially important indicator of neurodevelopmental vulnerability. Further investigation will look to identify specific EF domains that might be more strongly impacted compared to the global composite.