Exploring the Relationship Between Age of Nap Cessation, Screen-Positive Autism Spectrum Disorder Traits and Diagnosis of Attention-Deficit Hyperactivity Disorder.

PURPOSE: This study examined whether the age of nap cessation (the transition from daytime napping to sleeping exclusively at night) is associated with screen-positive Autism Spectrum Disorder (ASD) traits or an Attention-Deficit Hyperactivity Disorder (ADHD) diagnosis in children. METHODS: This retrospective cohort study used data from the Avon Longitudinal Study of Parents and Children (ALSPAC), a population-based birth cohort recruited between 1991 and 1992. The analytic sample included 6,424 children with available nap cessation and covariate data. Parents reported children's nap patterns at 6, 18, 30, 42, 57, 69, and 81 months. Binary logistic regression examined associations between age of nap cessation and later ASD traits or ADHD diagnosis. Models adjusted for gestational age, birth weight, maternal age, child sex, maternal ethnicity, older siblings, social class, and maternal alcohol use during pregnancy. RESULTS: Children who ceased napping by 18 months had higher odds of an ADHD diagnosis at age seven than those who ceased at 30 months (OR = 5.54, 95% CI [2.52, 11.20], p < .001). Nap cessation at 18 months was also associated with increased odds of ASD traits, although the estimate was less precise (OR = 1.81, 95% CI [0.96, 3.16], p = .051). CONCLUSIONS: Early nap cessation may be associated with later ADHD diagnosis and could reflect differences in sleep regulation. A possible association with elevated ASD traits was also observed but remains uncertain and should be considered exploratory pending replication. Nap cessation timing should not be interpreted as an early screening or diagnostic marker.