Effects of ketogenic diet on epileptiform activity in children with therapy resistant epilepsy

Purpose: The purpose was to quantify changes of epileptiform activity during ketogenic diet (0) treatment in children with therapy resistant epilepsy, and evaluate how these changes are related to activity stage and to clinical effects on seizure frequency, seizure severity, attentional behaviour, quality of life (QOL), and beta - hyd roxybutyrate (beta OHb). Methods: Eighteen children were investigated with 24h ambulatory EEG monitoring I week prior to KD initiation and, after 3 months of KD treatment. Epileptiform activity was evaluated by automated spike detection. This data was compared with data presented in a previous study published in Epilepsia 2006, on steep structure and different activity stages, clinical data on seizure frequency, seizure severity, QOL and attentional behaviour on the same children [Hallbook, T., Lundgren, J., Rosen, I., 2007. Ketogenic diet improves steep quality in children with therapy resistant epilepsy. Epilepsia 48, 59-65]. Results: After 3 months of KD treatment the number of interictal epileptiform discharges (IEDs) was significantly reduced (p < 0.001). When considering the four activity stages separately, the reduction was significant during non-rapid eye movement steep stage 2, slow wave steep (SWS) and rapid eye movement (REM) steep (p=0.001, 0.001, 0.002), and not significantly so during awake (p=0.07). Beta- hyd roxybutyrate was significantly increased (p<0.001). There was a significant correlation between the reduction in IEDs and clinical seizures (Spearman r=0.6, p=0.005) and between improvement in attentional behaviour and the increase in beta OHb (Spearman r=0.5, p=0.03). There was no significant correlation between changes in attentional behaviour and IEDs or clinical seizures. Conclusion: This study shows that KD reduces the number of IEDs, especially during steep. It shows a correlation between reduction in epileptiform activity and clinical seizures. There were no correlations between reduction in epileptiform activity and clinical seizures and improvement in QOL or attention. The increase in POHb correlated with improvement in attention. (c) 2007 Elsevier B.V. All rights reserved.