Abstracts

Rationale: Significant morbidity has been associated with delays in treatment or failure to respond to first-line treatments in patients with epileptic spasms (ES). The use of the ketogenic diet (KD) has become more popular in recent years for patients with refractory epileptic spasms. There is limited literature on the efficacy of the KD leading to a therapeutic response ( >50% reduction in seizures) in ES and even more limited data in relation to the etiology of the ES and response to the KD. Given the risks of neurodevelopmental decline and progression to Lennox Gastaut syndrome (LGS) in patients who fail to respond to first-line treatments, this study evaluated the efficacy of the KD in terms of seizure reduction as well as its impact on neurodevelopmental trajectory.  

Methods: A total of 13 patients with refractory ES who were then treated with the ketogenic diet were retrospectively identified from December 2019 to December 2021. Seizure reduction and neurodevelopmental responses to KD were determined by medical record review. Additional factors such as etiology, age at KD initiation, time from spasm diagnosis to initiation of KD, the maintenance KD ratio used, presence of new seizure types or progression to LGS, and any potential subsequent surgical interventions were also evaluated. 

Results: Documentation of seizure response to KD was available in 10 of the 13 patients. In those with quantifiable seizure reduction documented, 4 (31%) became seizure free, 1 had a 70-90% seizure reduction, 2 had a 50-70% seizure reduction, and 3 had an approximate 50% seizure reduction. The etiology was known in 12 with only one patient being unknown. Of those with a known etiology, 5 were due to genetic abnormalities, 3 were due to structural abnormalities, and 4 were due to perinatal injury. All patients with a perinatal injury as the etiology had an approximate 50% reduction in seizure burden. Otherwise, there was no clear association with etiology and seizure response rate. 3 patients went on to develop additional seizure types with only one of them formally progressing to LGS. There were clear neurocognitive improvements documented in 10 of the 13 patients. 7 patients (54%) had a clear improvement in development and 10 (77%) had a clear improvement in level of alertness. The maintenance KD ratio ranged from 2:1-4:1, and all patients achieved adequate ketosis. 

Conclusions: Our portion of patients with a therapeutic response to the KD was 77% with seizure cessation occurring in 31%. Those with perinatal injury all had an approximate 50% reduction in seizures. The most compelling finding in this study was the frequency of improvement in neurocognitive profiles. In those with cognitive documentation available, 100% had a clear improvement in level of alertness and 70% had an improvement in developmental trajectory. When evaluating the entire cohort, 77% had an improvement in encephalopathy and 54% had developmental improvement. Cognitive improvements were independent of seizure reduction which further supports the use of KD in patients with refractory ES.

Funding: None