Does the size of a ketogenic diet admission group influence outcomes?

Introduction: Most pediatric centers admit children with epilepsy for several days when initiating the ketogenic diet (KD). At some institutions, children are admitted in groups in order to save staff time and allow families to bond together for support. It is unknown if admitting children in larger groups for the KD affects outcomes.

Methods: We performed a retrospective study of all children with intractable epilepsy admitted for KD initiation at Johns Hopkins Hospital from 2010 to 2020. Charts were reviewed for size of admission groups, 3-month seizure reduction, and total KD duration. A linear mixed effects model was used to analyze KD duration between different size admission groups.

Results: 245 children were started on the KD, mean age 5.2 years. Thirty-three (13%) children were admitted in one-child admission groups, 52 (21%) in 2-children groups, 78 (32%) in 3-children groups, 72 (29%) in 4-children groups, and 10 (4%) in 5-children groups. At our center, fewer large admission groups and shorter KD durations have occurred over time. After adjusting for time, the 3-children admission group had higher KD duration than 1-child (1.9 times duration, p = 0.035). Additionally, after grouping cohort sizes into small (1-2 patients) versus large (3-5 patients), KD durations in the large groups were 1.6 times those in the small groups, p = 0.036. There was no statistically significant correlation between the size of the admission groups and 3-month seizure reduction.

Conclusions: Admitting children in larger groups, specifically 3 children at a time, was associated with longer KD durations. This may be due to parent support from groups, listening and learning from other parents' questions, or other factors.