Long-term outcomes of children treated with the ketogenic diet in the past

The ketogenic diet has well-established short- and long-term outcomes for children with intractable epilepsy, but only for those actively receiving it. However, no information exists about its long-term effects years after it has been discontinued.

Living subjects were identified who were treated at the Johns Hopkins Hospital with the ketogenic diet from November 1993 to December 2008 for >or=1 month, and had discontinued it >or=6 months prior to this study. Of 530 patients who were eligible, 254 were successfully contacted by phone or e-mail with a survey and request for laboratory studies.

Questionnaires were completed by 101 patients, with a median current age of 13 years (range 2-26 years). Median time since discontinuing the ketogenic diet was 6 years (range 0.8-14 years). Few (8%) still preferred to eat high fat foods. In comparison to the 52% responder rate (>50% seizure reduction) at ketogenic diet discontinuation, 79% were now similarly improved (p = 0.0001). Ninety-six percent would recommend the ketogenic diet to others, yet only 54% would have started it before trying anticonvulsants. Lipids were normal (mean total cholesterol 158 mg/dl), despite most being abnormal while on the ketogenic diet. The mean Z scores for those younger than age 18 years were -1.28 for height and -0.79 for weight. In those 18 years of age or older, the mean body mass index (BMI) was 22.2.

This is the first study to report on the long-term effects of the ketogenic diet after discontinuation. The majority of subjects are currently doing well with regard to health and seizure control.