Sleep in children with attention-deficit/hyperactivity disorder (ADHD) before and after 6-month treatment with methylphenidate: a pilot study

Children with ADHD may present with sleep disturbances that add to the impairment of the disorder. The long-term sleep effects of the first-line pharmacological treatment for ADHD, i.e., psychostimulants, are unclear. In this pilot study, we compared polysomnographic variables in children with ADHD (n = 11, aged 6-15 years), before pharmacological treatment, and in children without ADHD (n = 22, aged 5-14 years); we also assessed polysomnographic changes in children with ADHD (n = 7) after a 6-month treatment with methylphenidate immediate-release (once or twice daily). Compared to children without ADHD, those with ADHD at baseline presented with significantly increased duration of awakenings (p = 0.02), reduction in sleep efficiency (p = 0.03), and increase in stage I (N1) (p < 0.01) and reduction in stage II (N2) (p = 0.02) and stage III-IV (N3) percentages. Methylphenidate treatment did not significantly change any parameter of sleep architecture. Conclusion: Preliminary evidence from this pilot study shows that, compared to children without ADHD, those with ADHD presented a more fragmented and less effective sleep at baseline and that the 6-month methylphenidate treatment did not further negatively impact on sleep architecture.