Abstracts

Rationale: Ketogenic diets are effective for children with antiepileptic drug (AED) resistant epilepsy and are used in unique circumstances first-line or as monotherapy. These diets, such as the Modified Atkins Diet, are being used increasingly in adults as well and may be similarly effective as monotherapy in patients that wish to avoid AEDs.Methods: Adults (18 years and over) seen at the Johns Hopkins Adult Epilepsy Diet Center from August of 2010 to June of 2015 were prospectively enrolled in an observational study of ketogenic diets for epilepsy. History and EEGs were reviewed to confirm seizure type. Patients naive to diet therapy were started on a 20 gram per day net carbohydrate limit Modified Atkins Diet (MAD) and instructed to follow urine ketones (ketosis defined as ≥ 40 mg/dL), seizure frequency, and weights. Seizure reduction, diet compliance, side effects, and routine laboratory studies were assessed at 3-6 month intervals.Results: One hundred sixty-six patients were enrolled and of these, 4 were naive to AEDs (all female, ages 19-86 years, mean seizure frequency 5/week, range 2/year - 14/week). Diagnoses included idiopathic generalized epilepsy (1), and focal epilepsy (3). These four patients elected to pursue ketogenic diet therapy as an alternative to antiepileptic medication. Seven patients had previously tried one or more AEDs and stopped due to intolerable side effects (3 female, 4 male, age 18-52 years, mean seizure frequency 5/year, range 2/month – 1/15 year). Diagnoses included idiopathic generalized epilepsy (3) and focal epilepsy (4). Of 4 patients naive to AEDs, one was on a MAD at the time of the initial visit and 3 elected to begin MAD de novo. Two patients (50%) with focal epilepsy remain seizure-free at 4 and 9 months of diet treatment. Two (50%) had difficulty complying with MAD, never achieved urinary ketosis, and seizures continued. One of these patients (with IGE) was lost to follow up after 2 months and the other elected to try low glycemic index treatment but could not tolerate the carbohydrate restriction of either MAD or LGIT. Levetiracetam then lamotrigine were prescribed next after diet treatment was stopped but did not control seizures at high doses. Seven patients had tried one or more AEDs but stopped all AEDs prior to the first visit. Two were on MAD at the time of the first visit, 4 began MAD and 1 has yet to follow up. All 6 patients (100%) that began diet therapy remain on MAD and are seizure-free a mean of 13 months (range 2 – 26 months) after beginning MAD.Conclusions: For adults with new-onset epilepsy who are resistant to trying antiepileptic medications or have experienced intolerable side effects, a ketogenic diet such as the Modified Atkins Diet may be a feasible, safe, and effective alternative long-term.