Abstracts

Rationale: Dietary therapy is an adjunct treatment option for refractory epilepsy. Current dietary therapies are unable to provide all necessary nutrients, which can negatively impact growth and brain development. Thus, a nutrient dense dietary therapy may be useful in epilepsy. One potential option is the low glutamate diet, which limits consumption of free glutamate/aspartate, while maximizing nutrient intake. Glutamate is an excitatory neurotransmitter that can facilitate seizures. Blood-brain barrier permeability may allow circulating glutamate (from food) to enter the brain in higher amounts, which could potentiate seizures and disrupt neurological function. This study examined the effects of the low glutamate diet on pediatric epilepsy. _x000D_
Methods: Pediatric epilepsy patients (age 2-21 years), with ≥ 4 seizures/month, were recruited from the US and Canada. Participants underwent a baseline observation month and were then randomized into an intervention or wait-listed control (WLC) month. Controls continued onto an intervention month following the WLC period. During each month families completed a seizure diary, 3-day food diary, food-frequency questionnaire (FFQ), and online form. Change in seizure frequency, non-seizure improvement, and overall improvement based on a caregiver global impression of change (CGIC) were assessed between groups and after 1-month on the diet. A Student’s t-test or Mann Whitney U test was used for independent groups. Related samples were assessed via paired t-tests or Wilcoxon Signed Rank tests. Categorical data were analyzed via Chi-Square or Fisher’s Exact. Significant bivariate analyses of categorical data were followed by logistic regression._x000D_
Results: Data were analyzed from 33 subjects. Based on FFQ scores, subjects significantly reduced their consumption of foods commonly containing free glutamate/aspartate after 1-month on the diet (p< 0.001), indicating high compliance. However, there was no significant difference in seizure frequency between the intervention and WLC groups. Twenty-one percent of participants were clinical responders (achieved ≥ 50% seizure reduction) after 1-month. Age was a significant predictor of clinical response; with increasing age decreasing the likelihood of ≥ 50% seizure reduction by 21% (OR (95% CI) = 0.79 (0.62-1.00), p= 0.05). Sixty-three percent of caregivers reported non-seizure improvements after 1-month on the diet (Figure 1) and 31% reported improvements in their child’s overall health based on the CGIC. Increasing age was again observed to decrease the likelihood of overall health improvement (OR (95% CI) = 0.68 (0.51-0.90), p= 0.008). _x000D_