Ketogenic diet effectiveness is superior for drug resistant epilepsy with causative genetic mutation than those without genetic etiology

Aim: Epilepsy with genetic etiology is high prevalence of DRE, which is reported responsive to ketogenic diet therapy (KDT). Our retrospective cohort study attempted to investigate the KD responsiveness between DRE with genetic and non-genetic etiology.

Method: Non-fasting gradual KD initiation protocol (GRAD-KD) and five-day diet program was implemented. Participants were categorized into genetic epilepsy or non-genetic epilepsy groups based on genetic tests. Monthly seizure frequencies and seizure reduction rate after KDT 3 months and 6 months were compared between two groups.

Results: Forty-six patients with genetic epilepsy and ninety-four patients with non-genetic epilepsy were recruited. Among 46 patients with genetic epilepsy, 12 patients withdrew from diet before 3 months of KDT, and 7 patients withdrew from diet before 6 months of KDT, thus, 27 patients retained the diet. Among 94 patients with non-genetic epilepsy, 20 patients withdrew from diet before 3 months of KDT, and 21 patients withdrew from diet before 6 months of KDT, 53 patients retained the diet. For the 46 patients with genetic epilepsy, 12 patients had pathogenic variants related to developmental and epileptic encephalopathy (DEE), whereas other 34 patients had disease-causing variants other than DEE. The mean monthly seizure frequencies showed significantly decreased both in patient with genetic-and non-genetic epilepsy after 6 months of KDT, however, the seizure reduction rate was significantly higher in patients with genetic epilepsy than patients with non-genetic epilepsy after 6 months of KDT. In addition, our data demonstrated that KDT could significantly reduce seizure burden in patients with non-DEE than patients with DEE. In addition, the patients with non-DEE significantly achieved greater seizure reduction rate than patients with DEE after 6 months of KDT.

Interpretation: Our data highlighted that KD effectiveness is more outstanding in decreasing seizure burdens for epileptic patients with genetic etiology than those without causative gene mutation. Additionally, KDT is also significantly effective for decreasing more seizure burdens for non-DEE patients than for DEE patients. We suggested epileptic patients caused by genetic mutation should implement KDT as early as possible.