Provincial Disparities of Growth Hormone Coverage for Young Adult Survivors of Paediatric Brain Tumours across Canada Disparités provinciales dans la couverture pour l’hormone de croissance chez les jeunes adultes ayant survécu à une tumeur cérébrale infantile au Canada

Background: Young adult survivors of paediatric brain tumours (PBTs) who have been treated with radiation therapy will likely be severely growth hormone–deficient when retested at the achievement of final height. Growth hormone replacement therapy (GHRT) is administered to treat growth hormone deficiency (GHD). Public drug coverage for GHRT falls under the responsibility of provincial governments across Canada. This study sought to determine the extent of public drug coverage and cost in each Canadian province for GHRT to treat GHD during adulthood for young adult survivors of PBTs. Methods: Data were collected from provincial government resources and drug formularies from 2012–2013 on the extent of coverage for GHRT based on a clinical case scenario representative of a young adult survivor of a PBT with childhood-onset radiation-induced GHD, the ingredient cost for GHRT and the applicable provincial public drug plan cost-sharing policies. A model was then created to simulate out-of-pocket costs incurred by a young adult male and a young adult female survivor of a PBT for one year of GHRT in each province with applicable cost-sharing arrangements and levels of low annual individual total income that best represent the majority of young adult survivors of PBTs. Out-of-pocket costs were expressed as a percentage of annual income. Comparisons were made between provinces descriptively, and variation among provinces was summarized statistically. Results: Alberta, Manitoba, Ontario, Quebec, New Brunswick, and Newfoundland and Labrador provide coverage for GHD during adulthood on a case-by-case basis, while British Columbia, Saskatchewan, Nova Scotia and Prince Edward Island provide no coverage. The percentage of annual income to fund GHRT across the provinces without public coverage ranged from 14.4% to 25.5% for males and 21.5% to 38.3% for females, and with public coverage was 0.0% to 4.1% for males and 0.0% to 5.0% for females. Interpretation: There are considerable out-of-pocket costs and variation in coverage provided by provincial public drug plans to fund GHRT for young adult survivors of PBTs with GHD. The implementation of a national drug formulary could potentially prevent undue financial hardship and remove disparities resulting from variations in provincial drug plans. Résumé Contexte : Les jeunes adultes ayant survécu à une tumeur cérébrale infantile (TCI) après un traitement par radiothérapie demeurent très susceptibles de manifester une déficience en hormone de croissance lors d’un examen effectué à la fin de la croissance. L’hormonothérapie de remplacement (HTR) est employée pour traiter la déficience en hormone de croissance (DHC). Au Canada, la couverture publique de l’HTR est du ressort des gouvernements provinciaux. Cette étude visait à déterminer, pour chacune des provinces canadiennes, l’étendue et les coûts pour la couverture de l’HTR comme traitement de la DHC chez les jeunes adultes qui ont survécu à une TCI. Méthodes : Les données – recueillies entre 2012 et 2013 à l’aide des listes de médicaments et auprès de sources gouvernementales provinciales – portaient sur l’étendue de la couverture