Effects of antiepileptic drugs on sleep architecture: a pilot study

Objectives: The effects of antiepileptic drugs (AEDs) on sleep architecture are not well understood, especially in patients with localization-related epilepsy, in whom seizures themselves can disrupt sleep. To clarify the effects of AEDs on sleep architecture, we performed a prospective study, looking at sleep architecture in patients with epilepsy admitted for video-EEG monitoring. Methods: Adult patients with localization-related epilepsy treated with a single AED and admitted between 10/1997 and 04/2001 were included. Control patients on no AEDs were also included. Both groups were withdrawn from other AEDs. Overnight polysomnography was recorded and was scored according to the standard method. Adult patients with localization-related epilepsy on no medication were also recorded and served as controls. Patients with no seizure during the recording and no seizure in the 24 It preceding the recording were analyzed in this paper. Patients with a seizure in the 24 h preceding the recording and patients with a seizure during the recording were analyzed separately. Results: A total of 72 nights were recorded in 39 patients, and patients taking each AED were compared to controls. We did not find any statistically significant effect of carbamazepine (CBZ). Phenytoin (PHT) disrupted sleep by increasing stage 1 sleep (PHT: 13.2 +/- 7.3%; control: 7.7 +/- 4.8%; P = 0.008), and decreasing slow wave sleep (SWS) (PHT: 7.9 +/- 4.2%; control: 11.3 +/- 4.4%; P = 0.03) and REM sleep (PHT: 13.9 +/- 6.2; control: 18.8 +/- 5.1; P = 0.01). Valproic acid (VPA) disrupted sleep by increasing stage 1 sleep (VPA: 16.8 +/- 9.8%; control: 7.7 +/- 4.8%; P = 0.007). Gabapentin (GBP) improved sleep by increasing SWS (GBP: 19.4 +/- 4.2%; control: 11.3 +/- 4.4%; P = 0.0009). PHT and VPA disrupt sleep in the absence of seizures, while CBZ and lamotrigine have no significant effects. GBP improves sleep by increasing SWS. Conclusions: AEDs have differing effects on sleep structure, which can be beneficial or detrimental. Consideration of these potential effects is important in maintaining optimal sleep in patients with epilepsy. (C) 2002 Elsevier Science B.V. All rights reserved.