An economic evaluation of the ketogenic diet versus care as usual in children and adolescents with intractable epilepsy: an interim analysis

Objectives: To gain insight into the cost-effectiveness of the ketogenic (KD) diet compared with care as usual (CAU) in children and adolescents with intractable epilepsy, we conducted an economic evaluation from a societal perspective, alongside a randomized controlled trial.

Methods: Participants from a tertiary epilepsy center were randomized into KD (intervention) group or CAU (control) group. Seizure frequency, quality adjusted life years (QALYs), health care costs, production losses of parents and patient, and family costs were assessed at baseline and during a 4-month study period and compared between the intervention and control groups. The incremental cost-effectiveness ratios (ICERs) (i.e., cost per QALY and cost per responder), and cost-effectiveness acceptability curves (CEACs) were calculated and presented.

Results: In total, 48 children were included in the analyses of this study (26 KD group). At 4 months, 50% of the participants in the KD group had a seizure reduction >= 50% from baseline, compared with 18.2 of the participants in the CAU group. The mean costs per patient in the CAU group were (sic)15,245 compared to (sic)20,986 per patient in the KD group, resulting in an ICER of (sic)18,044 per responder. We failed, however, to measure any benefits in terms of QALYs and therefore, the cost per QALY rise high above any acceptable ceiling ratio. It might be that the quality of life instruments used in this study were not sufficiently sensitive to detect changes, or it might be that being a clinical responder is not sufficient to improve a patient's quality of life. Univariate and multivariate sensitivity analyses and nonparametric bootstrapping were performed and demonstrated the robustness of our results.

Significance: The results show that the KD reduces seizure frequency. The study did not find any improvements in quality of life and, therefore, unfavorable cost per QALY ratio's resulted.