Interface of epilepsy and sleep disorders

Obstructive sleep apnoea was first brought to prominence by Henri Gastaut, a French epileptologist. Since that time the interface between epilepsy and sleep disorders has received less attention than might be justified, recognizing that sleep deprivation is a poignant provocateur for seizures. Sleep deprivation is often used as a diagnostic procedure during electroencephalography (EEG) when waking EEG has failed to demonstrate abnormality. Patients referred to an outpatient neurological clinic for evaluation of possible seizures in whom sleep disorder was suspected, either due to snoring during the EEG or based on history, were evaluated with all-night diagnostic polysomnography (PSG) and appropriate intervention administered as indicated. Patient and seizure demography, sleep disorder and response to therapy were reviewed and the interface explored. Fifty patients aged between 10 and 83 years underwent PSG. Approximately half were diagnosed with epilepsy and almost three-quarters had sleep disorders sufficiently intrusive to require therapy (either continuous positive air pressure (CPAP) or medication). With co-existence of epilepsy and sleep disorders, proper management of sleep disorders provided significant benefit for seizure control. Snoring during EEG recordings could alert to the possibility of a sleep disorder even with epilepsy diagnosed. Where both epilepsy and sleep disorder coexist appropriate management of the sleep disorder improves control of the epilepsy.