Differences in rates of hypoglycemia and health care costs in patients treated with insulin aspart in pens versus vials

Abstract

Objectives:To study whether initiation of insulin aspart therapy with a pen vs. a vial/syringe has an impact on the risk of subsequent hypoglycemic episodes and health care costs.Methods:This was a longitudinal, retrospective analysis of the MarketScan and IMS LifeLink health plan claims databases for patients with type 1 or type 2 diabetes who initiated insulin aspart with a pen or a vial/syringe. Included were adults (≥18 years) who had received no short-acting insulin for the 6 months prior to their index date (date of first claim for either treatment) and who initiated treatment with insulin aspart with a pen or with a conventional vial/syringe during the period from January 1, 2004, through December 31, 2007, based on outpatient pharmacy claims data. Patients were excluded if they did not have at least two claims for the index treatment during the 12 month post-index period. Hypoglycemic episodes were identified by any claim containing a diagnosis code for hypoglycemia.Results:Analyses include 6065 patients in the pen group and 5523 patients in the vial/syringe group in the MarketScan database and 4512 patients in the pen group and 3782 patients in the vial/syringe group in the LifeLink database. Vial/syringe use was associated with 35% greater odds of at least one hypoglycemic episode than pen use in the MarketScan database (P < 0.001) and 44% greater odds in the LifeLink database (P < 0.001). Use of vials/syringes was associated with 89% and 62.7% greater health care costs for hypoglycemic events than use of pens, respectively (P < 0.001 for both databases). Patient groups were subject to selection bias as they did not have random assignment to treatment groups.Conclusions:In two independent claims databases, initiation of insulin aspart treatment with pen was associated with fewer hypoglycemic events and lower diabetes-related health care costs than initiation with vial/syringe.