Abstracts

Rationale: The ketogenic diet (KD) is a high-fat, low-protein, very low-carbohydrate diet used in the treatment of severe epilepsy in children. We observed that some children showed a decrease in their height velocity rate during diet. We examined the influence of the KD on linear growth and IGF-I levels in children with pharmacotherapy-resistant epilepsy. Methods: A prospective study was designed to evaluate growth, serum IGF-I levels, blood beta-hydroxybutyric acid (b-OHB), and seizure frequency before and during one year on the KD in 22 children. Their median age was 5.5 years and all had symptomatic epilepsy. Growth was assessed by measurements of height, height velocity, and body mass index (BMI). Standard deviation scores (SDS) were calculated for all measured parameters as well as for serum IGF-I in order to eliminate the influence of age and sex-related differences among patients. Results: Height, height velocity, BMI, and IGF-I decreased significantly during the KD. Height velocity decreased from -0.6±2.2 SD during the year before diet to -4.2±1.9 SD during diet. Serum IGF-I decreased from -1.1±1.0 SD before diet to -3.4±0.9 SD during diet. Height velocity correlated positively with IGF-I both before and during the KD. Furthermore, the slope of the regression line decreased significantly during the diet. Height velocity correlated negatively with b-OHB during the KD. Fourteen of the 22 children were seizure responders. No correlation was found between seizure response and growth alterations. Conclusions: A profound influence of the KD on growth and IGF-I levels was found. Height velocity was most affected in those with pronounced ketosis. Thus, in clinical practice, the level of ketosis should be related to gains in seizure response and growth. Our data indicate that the growth disturbances and the alteration of the dependence of growth on IGF-I are independent of seizure reduction.