Health economic comparison between continuous subcutaneous insulin infusion and multiple daily injections of insulin for the treatment of adult type 1 diabetes in Canada

Background: Patients with type 1 diabetes mellitus (DM) may be treated with insulin via multiple daily injections (MDI) or continuous subcutaneous insulin infusion (CSII).Objective: The purpose of this study was to evaluate the projected long-term cost-effectiveness of CSII compared with MDI by modeling a simulated sample of adult patients with type 1 DM in Canada.Methods: A health economic model was used to determine the incremental cost-effectiveness ratio (ICER) of CSII compared with MDI from the perspective of a Canadian provincial government. The primary input variable was change in glycosylated hemoglobin (HbA1c). A series of Markov constructs also simulated the progression of disease-related complications. Annual acquisition costs for CSII and MDI were year-2006 Can $6347.18 and Can $4649.69, respectively. A 60-year time horizon and a discount rate of 5.0% per annum on costs and clinical outcomes were used.Results: Mean direct lifetime costs were Can $15,591 higher with CSII treatment than MDI. Treatment with CSII was associated with an improvement in discounted life expectancy of 0.655 quality-adjusted life-years (QALYs) over a 60-year time horizon, compared with MDI (mean [SD], 10.029 [0.133] vs 9.374 [0.076] QALYs). ICERs were Can $27,264 per life-year gained and Can $23,797 per QALY for CSII compared with MDI. The results were most sensitive to HbA1c assumptions.Conclusion: Based on this analysis, CSII may be a cost-effective treatment option when compared with MDI in adult patients with type 1 DM in Canada.