Prevalence of EEG Paroxysmal Activity in a Population of Children with Obstructive Sleep Apnea Syndrome

Study Objectives: Sleep breathing disorders may trigger paroxysmal events during sleep such as parasomnias and may exacerbate preexisting seizures. We verified the hypothesis that the amount of EEG paroxysmal activity (PA) may be high in children with obstructive sleep apnea syndrome (OSAS). Design: Prospective study Settings: Sleep unit of an academic center. Participants: Polysomnographic studies were performed in a population of children recruited prospectively, for suspected OSAS, from January to December 2007, with no previous history of epileptic seizures or any other medical conditions. All sleep studies included 8 EEG channels, including centrotemporal leads. We collected data about clinical and respiratory parameters of children with OSAS and with primary snoring, then we performed sleep microstructure analysis in 2 OSAS subgroups, matched for age and sex, with and without paroxysmal activity. Measurements and Results: We found 40 children who met the criteria for primary snoring, none of them showed PA, while 127 children met the criteria for OSAS and 18 of them (14.2%) showed PA. Children with PA were older, had a predominance of boys, a longer duration of OSAS, and a lower percentage of adenotonsillar hypertrophy than children without PA. Moreover, PA occurred over the centrotemporal regions in 9 cases, over temporal-occipital regions in 5, and over frontocentral regions in 4. Children with PA showed a lower percentage of REM sleep, a lower CAP rate and lower A1 index during slow wave sleep, and lower total A2 and arousal index than children without EEG abnormalities. Conclusions: We found a higher percentage of paroxysmal activity in children with OSAS, compared to children with primary snoring, who did not exhibit EEG abnormalities. The children with paroxysmal activity have peculiar clinical and sleep microstructure characteristics that may have implications in the neurocognitive outcome of OSAS.