Dissertation (Doctoral) An Evaluation of a Universal Funding Program_for Insulin Pumps for Children and Teens with Type 1 Diabetes

Author

Rayzel Malka Shulman

Abstract

Pediatric insulin pump therapy has been broadly adopted despite equivocal evidence about long-term comparative effectiveness. This thesis aimed to elucidate the dynamics underlying observed patterns of pump use and outcomes in the context of a universal funding program for pediatric insulin pump therapy in Ontario, Canada. First we conducted interviews with physicians to understand why pumps have been broadly adopted. We found that physicians recognized that pumps fell short of expectations often because of lack of family or school support. Yet, pumps were valued in a number of ways. Second, we developed a survey and described the distribution of patients and resources amongst all 35 centres in the Ontario Pediatric Diabetes Network. We found differences in availability of diabetes team members and 24 hour support. Finally we performed two population-based cohort studies of youth with type 1 diabetes (<19 years) who received pump funding from 2006-2013 by linking our survey data to administrative databases. We found a higher proportion of patients using pumps were in the highest income quintile (29.6% compared to 19.1% of non-pump users). Overall pump use across centres was 38.1% (5.3-66.7 %). Pump uptake was not associated with centre characteristics. Discontinuation was low (0.42/100 person-years) and was not associated with centre characteristics. The rate of DKA was 5.28/100 person-years. There was a higher risk of DKA or death in youth who were more deprived (HR 1.53 (95% CI 1.01-2.31), p=0.0429) but no association of adverse events with access to 24 hour support. These findings suggest that the enthusiasm we observed for pump therapy may stem in part, from the different ways in which pump therapy is valued. Pump use is less common in lower income children and may result, in part, from physicians’ predisposition to recommend pump therapy to children with more support. We identified a number of patient characteristics associated with an increased rate of adverse events. Future research should focus on identifying the nuances of population and centre characteristics associated with pump use and adverse events that will inform the design of interventions aimed at improving appropriate access to and outcomes of pump therapy.


Supervisor

Astrid Guttmann


Co-Supervisor

Fiona A. Miller