The CORE-KDT study: a mixed methods protocol to establish core outcomes for refractory childhood epilepsy treated with ketogenic diet therapy.

BACKGROUND: A core outcome set defines the minimum outcomes that should be included in clinical trials, audit or practice. The aim being to increase the quality and relevance of research by ensuring consistency in the measurement and reporting of outcomes. Core outcome sets have been developed for a variety of disease states and treatments. However, there is no established set of core outcomes for refractory childhood epilepsy treated with ketogenic diet therapy. This should be developed using a patient-centred approach to ensure the outcomes measured are relevant to patients and clinical practice. METHODS: This is a mixed methods study of four phases to develop a core outcome set for refractory childhood epilepsy treated with ketogenic diet therapy. In phase 1, a systematic scoping review of the literature will establish which outcomes are measured in trials of refractory epilepsy treated with ketogenic diet therapy. In phase 2, qualitative interviews with parents and carers will aim to identify the outcomes of importance to these stakeholders. Phase 3 will see a comprehensive list of outcomes collated from the first two phases, grouped into domains according to an outcome taxonomy. Phase 4 will invite parents, health care professionals and researchers to participate in a two-round Delphi study to rate the importance of the presented outcomes. Following which, the core outcome set will be ratified at a face to face consensus meeting. DISCUSSION: This study will guide outcome measurement in future studies of childhood epilepsy treated with ketogenic diet therapy and clinical practice through audit and service evaluation.

Ketogenic dietary therapies for adults with epilepsy: feasibility and classification of response.

Ketogenic dietary therapies are an effective treatment for children with drug-resistant epilepsy. There is currently no high-quality evidence regarding ketogenic dietary therapies in adults, and further research has been recommended. This audit aimed to provide further evidence for the feasibility of dietary treatment for adults and to consider factors that may aid response classification in this population. We evaluated the effectiveness and tolerability of ketogenic dietary therapies in 23 adults with epilepsy attending specialist clinics. Medical notes were used to obtain seizure frequency information and other effects associated with dietary treatment. Individuals who achieved ≥50% seizure reduction at all follow-up points were classified as responders. Response rates, in terms of seizure frequency, were similar to those commonly reported in pediatric cohorts: 9/23 (39%) adults were classified as responders. These responders remained on the diet for at least one year (follow-up: 1-10 years). Other benefits reported by patients, but not quantified, included a reduction in seizure severity and increased alertness and concentration. Such factors often favor continuation of ketogenic dietary therapies despite a <50% seizure reduction. One individual experienced psychosis while following dietary treatment; most commonly reported adverse events were gastrointestinal. Adverse events did not lead to discontinuation of treatment in any cases. Our findings suggest that adults with epilepsy are able to follow ketogenic dietary therapies long-term, and such treatment can lead to seizure reduction. Other aspects besides seizure frequency may be relevant when classifying response in adults, and appropriate ways to quantify these factors should be considered for use in future studies.