The collateral effect of a brief behavioural sleep intervention on chronotype for autistic children: A brief report

Autistic children have approximately twice the risk of developing sleep problems and greater likelihood of a later circadian rhythm preference (chronotype) compared to non-autistic peers, which together impact health and wellbeing. However, the interplay between underpinning biological, psychological, and environmental factors remains poorly understood. This pilot study explored the collateral effect of a behavioural sleep intervention for autistic children without caregiver reported intellectual disability ( n = 49, M age = 8.80 [2.14], 51 % female) on children’s chronotype (morningness/intermediate/eveningness) according to naturalistic melatonin use/non-use (65 %). Intervention group participants ( n = 25) completed a brief three-session sleep intervention. All caregivers completed the Children’s Chronotype Questionnaire morningness/eveningness subscale (CCTQ) and Children’s Sleep Habits Questionnaire (CSHQ) at baseline and three-months post-randomisation. Single case analyses compared reliable change for children with and without melatonin use. A Wilcoxon Signed-Rank test compared chronotype for each group pre- and post-intervention. The magnitude of change in chronotype score following intervention was greater for children not using melatonin. However, this difference was less marked for the sleep problem severity score. Fifty-seven percent of children had an eveningness chronotype at baseline. For the intervention group, there was a significant median change in chronotype category, z = 4.50, p = .013 with a reduction in eveningness chronotype from 15 to nine children. For the treatment as usual group there was no significant change, z = 10.50, p = 1.000. These preliminary findings provide novel insight and suggest the potential collateral effect of behavioural sleep intervention on chronotype. • Despite melatonin supplementation, 65 % of autistic children reported sleep problems. • Shift to earlier chronotype for autistic children following behavioural intervention. • Magnitude of change in chronotype greater for autistic children not taking melatonin. • Potential collateral effect of behavioural intervention on autistic child chronotype. • Future research with larger samples and objective measures needed.