Assessment of adherence and healthcare costs of insulin device (FlexPenA®) versus conventional vial/syringe

Diabetes is difficult to manage and treatment involves significant lifestyle adjustments. Unlike the traditional method of insulin administration via the vial and syringe method, insulin pens might be perceived as less cumbersome and have potential to significantly increase patient adherence. Using "real world" data, we examined the differences in adherence and costs between diabetic patients using an insulin FlexPenA (R) (Novo Nordisk Inc, Princeton, NJ, USA) and those using traditional vial and syringe administration. Using a retrospective analysis of health insurance claims data between the years 2003 and 2008, we examined patients in the FlexPen cohort and analog vial cohort. Propensity score matching was used to match these cohorts (n=532 in each) according to baseline characteristics. Adjusted mean medication possession ratio when switched to FlexPen improved by 22 percentage points versus 13 percentage points when continuing to use vials (P=0.001). Diabetes-related healthcare costs when switched to FlexPen versus continuing on to use vials ($3970 vs. $4838, respectively, P=0.9368) and total healthcare costs ($13,214 vs. $13,212, respectively, P=0.9473) were not statistically different. Without significant addition to the cost, insulin administration with FlexPen is associated with an improved adherence among patients who switched from vial-based insulin administration.