We reviewed the records of 63 adult epilepsy patients who underwent po
lysomnograms in our laboratory since 1985 to determine the indications
for polysomnography and the results of testing. Reasons for referral
included excessive daytime sleepiness, suspected obstructive sleep apn
ea (OSA), and characterization of nocturnal spells. The most common po
lysomnographic diagnosis was OSA, although we also found narcolepsy, i
nsufficient sleep syndrome with possible idiopathic hypersomnolence, a
nd previously unrecognized nocturnal seizures. We treated OSA with con
tinuous positive airway pressure in 28 patients, 15 of whom were using
the device at follow-up appointments. The majority of patients treate
d for OSA or other disorders reported an improvement in sleepiness or
seizure control. Polysomnography, when indicated, is beneficial in epi
lepsy patients.