Diagnostic value of spontaneous afternoon sleep in epilepsy: polysomnographic study of 96 epileptic patients

An early afternoon polysomnographic recording was performed in 112 epileptic patients in order to better define their epileptic disease. 96 subjects (85.7%) slept spontaneously and sleep EEG tracing resulted in diagnostically useful data in 47.8% of cases, a significantly higher percentage than that obtained from tests performed in basal conditions. EEG activation, mostly linked to light NREM sleep stages, was greater in infanto-juvenile subjects than in adults.