Six-month efficacy of the Ketogenic diet is predicted after 3 months and is unrelated to clinical variables

Objective: The aim of this study was to evaluate the 6-month efficacy of a Ketogenic diet (KD) in children with drug-resistant epilepsy and to analyze the associated factors that affect the efficacy of a KD. Methods: Eighty-seven pediatric patients with drug-resistant epilepsy who followed a KD for at least 6 months were included in this study. The efficacy of a KD was assessed based upon the seizure frequency, as recorded by parents and caregivers. The number of cases and the degree of efficacy in different age ranges were also considered. The effects of gender, age, seizure type, etiology, blood glucose and ketone levels, seizure frequency before the diet, and cognition on the length of time on a KD were analyzed. Results: (1) There was no significant correlation between the length of time on a KD and efficacy (chi(2) = 2.31, P = 0.51). The 3-month efficacy of a KD was 51%, which did not further increase when the course was extended to 6 months. (2) There was a positive correlation between increased cognition and the efficacy of a KD after 3 months (gamma = 0.31, P = 0.003). (3) The efficacy analysis of 3-month treatment with a KD revealed, with respect to seizure types, that there were 37 patients with multiple seizure phenotypes and 50 patients with a single seizure phenotype. The overall efficacy of a KD in the group with multiple seizure phenotypes was 61%. The efficacy of a KD was not statistically associated with a coexisting syndrome or a type of syndrome; however, the efficacy of a KD had a tendency to be increased in certain types of syndromes. The overall efficacy in the group with a single seizure phenotype was 87%, and the efficacy was not associated with seizure type. (4) The 3-month efficacy of a KD was not correlated with age, gender, etiology, blood glucose or ketone levels, or the seizure frequency before treatment. Conclusion: An observation time of 3 months is appropriate for assessing the efficacy of a KD in treating children with drug-resistant epilepsy. The factors that likely influence the efficacy of a KD are unclear, but our study suggests that incorporating more patient samples will help determine whether patients with certain syndromes can benefit from a KD. (C) 2015 Elsevier Inc. All rights reserved.