title: Long-term clinical outcomes and economic evaluation of the ketogenic diet versus care as usual in children and adolescents with intractable epilepsy.
abstract: To examine long-term retention rate, clinical outcomes, cost-utility and cost-effectiveness of the Ketogenic Diet (KD) compared with care as usual (CAU) in children and adolescents with intractable epilepsy from a societal perspective.
  
  
  
  Participants were randomized into a KD or CAU group. Seizure frequency, quality adjusted life years (QALYs), side-effects, seizure severity, health care costs, production losses, patient and family costs were assessed at baseline and during 16-months of follow-up. Incremental cost-effectiveness ratios (ICERs) (i.e. cost per QALY and cost per responder) and cost-effectiveness acceptability curves are presented.
  
  
  
  48 children were included in the analyses of this study (26 from KD group). In total, 58% of the KD group completed the follow-up of 16 months; 11 dropped-out for various reasons. At 16 months, 35% of the KD participants had a seizure reduction≥50% from baseline, compared with 18% of the CAU participants. Mean costs per patient in the CAU group were €53,367 (extrapolated) compared to €61,019 per patient in the KD group, resulting in an ICER of €46,564 per responder. Cost per QALY rose well above any acceptable ceiling ratio. At 4-months' follow-up, the KD group showed significantly more gastro-intestinal problems compared to the CAU group. At 16 months, the KD group reported fewer problems compared to CAU. Furthermore, 46.2% of the KD group reported a decrease in severity of their worst seizure compared to 32% of the CAU group.
  
  
  
  The KD group resulted in more responders and showed greater improvement on seizure severity. Furthermore, the KD did not lead to worsening of side-effects other than gastro-intestinal problems (only at 4 months' follow-up). However, as only a minimal difference in QALYs was found between the KD group and the CAU group, the resulting cost per QALY ratios were inconclusive.
authors.affiliation: Department of Health Services Research, CAPHRI School for Public Health and Primary Care, Maastricht University, Maastricht, The Netherlands; Department of Research and Development, Epilepsy Center Kempenhaeghe, Heeze, The Netherlands. Electronic address: B.wijnen@maastrichtuniversity.nl.
authors.forename: Ben F M
authors.initials: BFM
authors.lastname: Wijnen
authors.affiliation: Department of Health Services Research, CAPHRI School for Public Health and Primary Care, Maastricht University, Maastricht, The Netherlands; Department of Research and Development, Epilepsy Center Kempenhaeghe, Heeze, The Netherlands; Trimbos Institute, National Institute of Mental Health and Addiction, Utrecht, The Netherlands.
authors.forename: Reina J A
authors.initials: RJA
authors.lastname: de Kinderen
authors.affiliation: Department of Neurology, Academic Center for Epileptology Kempenhaeghe & Maastricht UMC+, Heeze, The Netherlands.
authors.forename: Danielle A J E
authors.initials: DAJE
authors.lastname: Lambrechts
authors.affiliation: Department of Research and Development, Epilepsy Center Kempenhaeghe, Heeze, The Netherlands.
authors.forename: Debby
authors.initials: D
authors.lastname: Postulart
authors.affiliation: Department of Research and Development, Epilepsy Center Kempenhaeghe, Heeze, The Netherlands; Department of Behavioral Sciences, Epilepsy Center Kempenhaeghe, Heeze, The Netherlands; Department of Neurology, Maastricht University Medical Center, Maastricht, The Netherlands; Faculty of Electrical Engineering, University of Technology, Eindhoven, The Netherlands.
authors.forename: Albert P
authors.initials: AP
authors.lastname: Aldenkamp
authors.affiliation: Department of Research and Development, Epilepsy Center Kempenhaeghe, Heeze, The Netherlands; Department of Neurology, Academic Center for Epileptology Kempenhaeghe & Maastricht UMC+, Heeze, The Netherlands; Department of Neurology, Maastricht University Medical Center, Maastricht, The Netherlands; School of Health Professions Education, Faculty of Health, Medicine and Life Sciences, Maastricht University, The Netherlands.
authors.forename: Marian H J M
authors.initials: MHJM
authors.lastname: Majoie
authors.affiliation: Department of Health Services Research, CAPHRI School for Public Health and Primary Care, Maastricht University, Maastricht, The Netherlands; Trimbos Institute, National Institute of Mental Health and Addiction, Utrecht, The Netherlands.
authors.forename: Silvia M A A
authors.initials: SMAA
authors.lastname: Evers
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D003362:Cost-Benefit Analysis; D055423:Diet, Ketogenic / Q000379:methods; D000069279:Drug Resistant Epilepsy / Q000178:diet therapy* / Q000191:economics; D005260:Female; D017048:Health Care Costs; D006801:Humans; D008297:Male; D011788:Quality of Life; D019057:Quality-Adjusted Life Years; D013995:Time
keywords: Adolescents; Children; Economic evaluations; Epilepsy; Intractable epilepsy; Ketogenic diet