Clinical and sleep profile of children with specific learning disorders, attention deficit hyperactivity disorder, or both: a retrospective multicenter study

BACKGROUND: Sleep disturbances are frequently reported in children with neurodevelopmental disorders (NDD), particularly attention-deficit/hyperactivity disorder (ADHD). However, sleep in children with specific learning disorders (SLD) remains poorly characterized. This study aimed to compare clinical and polysomnographic (PSG) sleep profiles of children with SLD, ADHD, or comorbid SLD-ADHD presenting with sleep complaints. METHODS: In this retrospective multicenter study, 146 children aged 6-18 years underwent PSG across three sleep centers and were classified into three groups: SLD (n = 60), SLD-ADHD (n = 50), and ADHD (n = 36). Clinical data, sleep complaints, the French Sleepiness Scale adapted for children (FSSA), and PSG parameters were analyzed using multinomial regression and mixed models. RESULTS: Overall, 38.0% of children reported daytime sleepiness and 39% reported insomnia complaints. FSSA scores were significantly higher in the SLD and SLD-ADHD groups than in the ADHD group (p = 0.01), while insomnia complaints was more frequent in the ADHD group (58.3% vs 26.7%, p = 0.009). On PSG, 25-30% had mild obstructive sleep apnea. The SLD and SLD-ADHD groups showed greater NREM sleep fragmentation, higher respiratory arousal indices, and a higher prevalence of pathological periodic limb movements compared to ADHD. In multivariate analyses, SLD group membership and anxiety were independently associated with higher FSSA scores. CONCLUSIONS: In this sleep-clinic sample, children with SLD exhibited greater subjective daytime sleepiness and NREM sleep fragmentation despite fewer insomnia complaints than those with ADHD, underscoring the importance of systematic sleep assessment in this population.