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 (KD) 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-hydroxybutyrate (betaOHb).

METHODS

Eighteen children were investigated with 24h ambulatory EEG monitoring 1 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 sleep structure and different activity stages, clinical data on seizure frequency, seizure severity, QOL and attentional behaviour on the same children [Hallbook, T., Lundgren, J., Rosén, I., 2007. Ketogenic diet improves sleep 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 sleep stage 2, slow wave sleep (SWS) and rapid eye movement (REM) sleep (p=0.001, 0.001, 0.002), and not significantly so during awake (p=0.07). Beta-hydroxybutyrate 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 betaOHb (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 sleep. 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 betaOHb correlated with improvement in attention.