Decision Models for Assessing the Cost Effectiveness of Treatments for Pediatric Drug-Resistant Epilepsy: A Systematic Review of Economic Evaluations
Drug-resistant epilepsy affects about one-third of children with epilepsy and is associated with high costs to the healthcare system, yet the cost effectiveness of most treatments is unclear. Use of cannabis-based products for epilepsy is increasing, and the cost effectiveness of such strategies relative to conventional pharmacologic treatments must be considered.
The objective of this systematic review was to identify economic evaluations of cannabis-based treatments for pediatric drug-resistant epilepsy. We also sought to identify and appraise decision models that have been used in economic evaluations of pharmacologic treatments (i.e., antiepileptic drugs) in this population.
Electronic searches of MEDLINE, EMBASE, and the Cochrane library, as well as a targeted grey literature search, were undertaken (11 June 2018). Model-based full economic evaluations involving cannabis-based treatments or pharmacologic treatments for drug-resistant epilepsy in children were eligible for inclusion. Two independent reviewers selected studies for inclusion, and study quality was assessed by use of the Drummond and Consolidated Health Economic Evaluation Reporting Standards (CHEERS) checklists. Study findings, as well as model characteristics, are narratively summarized.
Nine economic evaluations involving children with drug-resistant epilepsy were identified; however, none involved cannabis-based treatments. All studies involved pharmacologic treatments compared with other pharmacologic treatments or non-pharmacologic treatments (i.e., ketogenic diet, epilepsy surgery, vagus nerve stimulation). Few studies have assessed the cost effectiveness of pharmacologic treatments in specific drug-resistant epilepsy syndromes, including Dravet and Lennox-Gastaut syndromes. Five included studies involved use of Markov models with a similar structure (i.e., health states based on seizure frequency relative to baseline). There was a wide range of methodological quality, and few studies fully addressed context-specific issues such as weight gain and treatment switching.
Whether cannabis-based treatments for pediatric drug-resistant epilepsy represent good value for money has yet to be investigated. Economic evaluations of such treatments are needed and should address issues of particular importance in pediatric epilepsy, including weight gain over time, switching or discontinuation of treatments, effectiveness of interventions and comparators, and long-term effectiveness beyond the duration of available clinical studies.
Compliance with Ethical Standards
No specific funding was obtained for this study. Jesse Elliott is supported by an Ontario Graduate Scholarship.
Conflict of interest
Bláthnaid McCoy is principal investigator in a study of cannabinoids for Dravet syndrome. Jesse Elliott, Sasha van Katwyk, Tammy Clifford, Beth Potter, Becky Skidmore, George Wells, and Doug Coyle have no conflicts of interest to declare.
JE, TC, DC, BP, BM, GW, and DC designed the study. BS developed and executed the search strategy. JE, SVK, and DC selected studies for inclusion and extracted data. JE analyzed the data and wrote the first draft of the manuscript, which was critically revised for intellectual content by all authors. All of the authors contributed to the conception and planning of the study, the analysis and/or interpretation of the data, drafting and critical revision of the manuscript, and approved the final version submitted for publication.
Data Availability Statement
All data generated or analyzed during this study are included in this published article (and its supplementary information files [Electronic Supplementary Material]).
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