Gabapentin-induced modulation of interictal epileptiform activity related to different vigilance levels

Objectives: Gabapentin (GBP) is a novel antiepileptic drug (AED), currently used as add-on therapy in patients with partial seizures. Similar to other AEDs, little is known about its effects on nocturnal sleep, despite the strict relationship between sleep and epileptic discharges. The aim of our study was to evaluate the effects of chronic therapy with GBP on both nocturnal sleep and on interictal epileptiform abnormalities (IEA) in relation to the different sleep stages. Methods: Eighteen patients affected by partial seizures resistant to common AEDs were submitted to nocturnal polygraphic recordings under baseline conditions and after 4 months of add-on GBP treatment. Results: We observed a significant increase in unilateral/focal IEA during light NREM sleep and a significant reduction in bilateral/diffuse IEA during wakefulness after sleep onset (WASO) with respect to the baseline condition. A significant increase in REM sleep and slow wave sleep (SWS) associated with a reduction in the number of awakenings and Stage 1 was also observed after GBP chronic therapy. Conclusions: GBP therapy improves the sleep pattern of epileptic patients and it seems to modulate the expression of IEA with different effects in relation to the various vigilance levels. (C) 2000 Elsevier Science Ireland Ltd. All rights reserved.