Fetal exposure to tobacco smoke and offspring early-life neurodevelopment in the Healthy Start study

Abstract

TPS 731: Neurological effects in children, Exhibition Hall, Ground floor, August 26, 2019, 3:00 PM - 4:30 PM Background: Fetal exposure to tobacco is linked to impaired cognitive ability in the offspring. It is not clear whether these associations persist in the absence of other known risk factors, such as pre-term delivery and low birth weight. We aimed to explore the associations between fetal exposure to tobacco with cognitive function, independent of pre-term delivery or low birth weight. Methods: We followed 246 mother-child pairs enrolled in the Healthy Start cohort through age 4.5 years, who were born full-term (≥37 weeks gestation) and with a birth weight>2,500-g. Maternal urinary cotinine was measured at 27 weeks gestation. At age 4.5 year, parents completed the Third Edition Ages and Stages Questionnaire (ASQ-3) and children completed the National Institutes of Health (NIH) Toolbox Cognition Battery. The five domains of the ASQ-3 were dichotomized as fail/monitor and pass. Logistic regression models examined the association between cotinine categories (below limit of detection (LOD) or ≥LOD) and the five ASQ-3 domains as separate outcomes. Linear regression models examined the association between cotinine categories and fully-adjusted T-scores for inhibitory control (Flanker test), cognitive flexibility (Dimensional Change Card Sort test), and receptive language (Picture Vocabulary test). Our models adjusted for sex, race/ethnicity, maternal age, maternal education, and maternal psychiatric diagnosis. Results: Approximately 65 of the 246 children were exposed to some level of tobacco during pregnancy. Compared to non-exposed offspring, those prenatally exposure to tobacco were more likely to have a fail/monitor score for fine motor skills (adjusted odds ratio: 3.9, 95% CI: 1.6, 9.9) and to exhibit decreased inhibitory control (adjusted beta coefficient: -3.5, 95% CI: -6.5, -0.4). Conclusions: Any exposure to tobacco in utero may have long-lasting effects on cognitive ability, independent of other known risk factors. Increased developmental screening may be warranted for children prenatally exposed to tobacco.