Comparison of antiepileptic drug levels in sudden unexpected deaths in epilepsy with deaths from other causes

Purpose: (a) To compare postmortem antiepileptic drug (AEB) levels in patie nts with sudden unexpected death in epilepsy (SUDEP) with those in a contro l group of subjects with epilepsy. If SUDEP patients more frequently had un detectable or subtherapeutic AED levels, this would suggest that compliance with AED treatment is poorer in this group and that poor compliance is a r isk factor for SUDEP. (b) To determine whether a particular AED was detecte d more commonly in the SUDEP group, suggesting that this AED is associated with a higher risk of SUDEP. Methods: A retrospective study of coronial cases was performed. Postmortem AED levels in 44 SUDEP cases and 44 control cases:were compared, The contro l group consisted of epileptics who died of causes other than epilepsy, inc luding natural disease (e.g., ischemic heart disease, accidents, and suicid e). The AEDs measured included carbamazepine (CBZ), phenytoin, (PHT), valpr oate (VPA), phenobarbitone (PB), lamotrigine (LTG), clonazepam (CZP), and c lobazam (CLB). The number of SUDEP and control cases in which CBZ only was- detected were compared, as were the number in which PHT only was detected. Results: Compared with the controls, the SUDEP group showed no difference i n the number with no detectable AEDs (13 vs. 11), the number with subtherap eutic AEDs (10 vs. 13), and the number with therapeutic levels (21 in both groups). CBZ only was detected in 11 SUDEPs and 11 controls, and PHT only i n five SUDEPs and 10 controls. Conclusions: Our study suggests the SUDEP group were no less compliant with AED treatment than the control group. This study does not support the hypo thesis that poor compliance with AED treatment is a risk factor for SUDEP. There was no evidence that; PHT or CBZ is associated with a higher risk of SUDEP.