Sleep apneas and epilepsy comorbidity in childhood: a systematic review of the literature.

PURPOSE: Our aim is to review studies which assess the prevalence of sleep apneas in children with epilepsy and discuss possible mechanisms linking these two conditions, as well as the impact of sleep apneas on the prognosis of these children.
METHODS: PubMed was used as the medical database source, and articles were selected and classified according to their originality, level of evidence, and relevance to the broad scope of the review.
RESULTS: Children with epilepsy have a higher prevalence of sleep breathing disorders in comparison to healthy children, but this prevalence varies widely depending on the methodology of each study. Major risk factors for sleep apneas in childhood epilepsy include mainly poor seizure control and antiepileptic drug polytherapy. Indeed, epilepsy can trigger sleep apneas, as abnormal electrical discharge amplifies sleep-induced breathing instability, antiepileptic drugs disturb muscle tone, and vagus nerve stimulation modulates neurotransmission to airway muscles. On the other hand, sleep apneas enhance sleep fragmentation, thus reducing the threshold for the appearance of seizures. Moreover, they have a negative effect on the neurocognitive profile of these children, as they disturb neuroplasticity mechanisms and also have a probable association with sudden unexpected death in epilepsy. The surgical treatment of sleep apneas has been found to reduce seizure frequency, and this can offer new therapeutic choices.
CONCLUSIONS: Between sleep apneas and childhood epilepsy, there is a complex relationship with reciprocal interactions. The presence of sleep apneas should be taken into account when designing the management of these children, as it creates therapeutic opportunities and limitations.