Exploratory Analysis of Sleep–Wake Rhythms and Sensory Processing in School-Aged Children with Autistic Spectrum Disorder: An Actigraphic Study

Purpose: This study aimed to explore and examine the relationship between sleep-wake rhythms and sensory processing characteristics in school-age children with autistic spectrum disorder (ASD) using objective sleep measurement indices. Patients and Methods: This cross-sectional exploratory study included 30 children with ASD aged 6– 9 years. Sleep–wake rhythms were recorded continuously for at least 14 days using a waist-worn actigraph (MTN-220) and analyzed with SleepSign Act. Sensory processing ability was assessed using the Japanese version of the Sensory Profile (SP-J), with SP-J quadrant and sensory processing scores. Associations between sleep variables and SP-J quadrant and sensory processing scores were examined using Spearman’s rank correlation coefficient, applying Bonferroni correction within each pre-specified correlation set. Results: Of the 30 children initially enrolled, 11 were excluded, yielding data from 19 participants. After Bonferroni correction, no significant associations were found between SP-J quadrant scores and sleep variables ( r = − 0.411– 0.540). Regarding associations with sensory processing scores, the oral sensory score showed a positive correlation with the mean wake time ( r = 0.698, p = 0.006). However, no other significant associations were found between sensory processing scores and sleep variables. Conclusion: These results suggest that the relationship between oral sensory scores and the average wake time remains strong even during the school-age period when sleep–wake rhythms change. Although exploratory, this study provides foundational insights with clinical significance for understanding and supporting sleep disorders in children with ASD. Keywords: sleep–wake rhythm, autistic spectrum disorder, school-aged children, sensory processing, actigraphy