Melatonin is one of the most used pharmacologic treatments for sleep problems in autism spectrum disorder, though its relationship with circadian and sleep parameters is still not well stablished. A naturalistic study was conducted in children with autism spectrum disorder, previously drug-naïve, before and after treatment with immediate-release melatonin. Circadian rhythms and sleep parameters were studied using an ambulatory circadian-monitoring device, and saliva samples were collected enabling determination of dim light melatonin onset. Twenty-six children with autism spectrum disorder (age 10.50 ± 2.91) were included. Immediate-release melatonin modified circadian rhythm as indicated by wrist skin temperature, showing an increase at night. A positive correlation was found between time of peak melatonin and sleep efficiency improvement values. Sleep-onset latency and efficiency improved with immediate-release melatonin. Immediate-release melatonin could be an effective treatment to improve sleep onset and restore a typical pattern of wrist temperature, which appears to be lost in autism spectrum disorder.
Keywords: actigraphy; autism spectrum disorder; circadian rhythm; melatonin; sleep; temperature.