Long-term effectiveness and seizure recurrence risk factors of ketogenic diet for pediatric refractory epilepsy: Experience from a tertiary care center in China.

ABSTRACT

OBJECTIVE: This study aimed to assess the long-term effectiveness and seizure recurrence risk in children with drug-resistant epilepsy who achieved seizure freedom on a ketogenic diet (KD). Predictors associated with seizure recurrence were also evaluated. METHODS: Patients with drug-resistant epilepsy who received KD therapy for at least 3 months between May 2011 and April 2020 were included. The clinical efficacy of the KD was evaluated. Patients who achieved seizure freedom for at least 3 months on the KD were focused. Multivariate Cox regression models were used to explore the risk factors of seizure relapse in patients who achieved seizure freedom. RESULTS: This study included 288 patients (163 males, 125 females). The seizure-free rates of the KD at 3, 6, 12, and 24 months were 9.7%, 16.7%, 14.2%, and 9.0%, respectively. Additionally, the seizure reduction rates between 50% and 99% were 46.5%, 39.9%, 30.2%, and 20.5%, respectively. Patients with Angelman syndrome (AS) showed the highest efficacy rate, followed by those with Dravet syndrome (DS). 51 patients achieved at least 3 months of seizure freedom on the KD. Seizures recurred in 24 (47.1%) patients. None of the patients with AS relapsed, while those with DS had the highest recurrence rate. The etiology of epilepsy, KD maintenance treatment period, and electroencephalography (EEG) abnormalities during follow-up differed significantly between patients with and without recurrence. However, multivariate Cox regression analysis indicated that a KD maintenance treatment period of less than 12 months and the presence of EEG abnormalities during follow-up were significantly correlated with a higher risk of relapse. Epilepsy control was restored in 3 of the 24 (12.5%) patients who experienced relapse. SIGNIFICANCE: KD appears to be effective in children with various types of drug-resistant epilepsy. A short KD maintenance treatment period and EEG abnormalities during follow-up were associated with an increased risk of seizure recurrence.