Clinical impact of initiating insulin glargine therapy with disposable pen versus vial in patients with type 2 diabetes mellitus in a managed care setting.

To investigate health care utilization, cost, and clinical outcomes among non-insulin-treated patients with type 2 diabetes mellitus who initiated insulin glargine therapy with use of either a disposable pen or vial and syringe in a managed care setting in the United States. This retrospective cohort study of a large national claims database consisted of a 6-month baseline period and a follow-up period extending 12 months from the date of the patient's first filled insulin glargine prescription. Outcomes included medication persistence, hypoglycemic events, health care utilization and costs, and glycosylated hemoglobin A1c (A1C) levels. There were 3,842 matched patients (n = 1,921 per group). Patients initiating insulin glargine therapy with a disposable pen were significantly less likely to discontinue or switch treatment during the 12-month follow-up period versus patients in the vial and syringe group (P<.001). Disposable pen use was also associated with a reduced hypoglycemia risk. The disposable pen group had overall health care utilization similar to the vial and syringe group; however, the pen group had significantly fewer diabetes-related hospitalizations (P = .04) and significantly more diabetes-related endocrinologist visits (P = .04). Overall health care costs were similar between the 2 groups, despite higher pharmacy costs in the disposable pen group. In a subgroup of patients with available baseline and follow-up A1C values (n = 511), the disposable pen group achieved similar A1C control at follow-up despite a higher baseline A1C value than in the vial and syringe group. Initiation of insulin glargine therapy with a disposable pen in patients with type 2 diabetes was associated with better treatment persistence and decreased hypoglycemia in comparison with the vial and syringe method, without any increase in total health care utilization or costs.