A comparison of insulin use, glycemic control, and health care costs with insulin detemir and insulin glargine in insulin-naive patients with type 2 diabetes

Abstract

Objectives: The goal of this study was to compare daily insulin use, glycemic control, and health care costs in insulin-naive patients with type 2 diabetes who initiated treatment with either insulin detemir or insulin glargine. Methods: This was a retrospective cohort analysis of health care claims data and laboratory results for adult, insulin-naive patients with type 2 diabetes who were enrolled in a large US managed care organization and initiated basal therapy with insulin detemir or insulin glargine between May 1, 2006, and December 31, 2006. The daily average consumption (DACON) of insulin was calculated as the total number of units dispensed (excluding the last fill) divided by the number of days between the index date and the date of the last fill of the index insulin. Glycemic control was evaluated by comparing mean glycosylated hemoglobin (HbA 1c) values in the preindex period (the 180 days before the index date) and the follow-up period (the 180 days after the index date). Mean all-cause and diabetes-related health care costs in the preindex and follow-up periods were calculated and compared. Results: The analysis included 48 patients initiating therapy with insulin detemir and 258 initiating therapy with insulin glargine. The mean age of the 2 cohorts was ~54 years, and most patients in each cohort were male (52.1% and 59.7%, respectively). Few patients in either cohort had a baseline HbA 1c value <7% (13% and 10%), suggesting poor glycemic control at the time of insulin initiation. After adjustment for confounders (eg, preindex diabetes medication), the DACON of insulin was comparable between cohorts (29.3 and 29.6 U/d; P = NS), as were follow-up HbA 1c values (8.2% and 7.9%). Insulin detemir and insulin glargine also were associated with comparable mean adjusted all-cause pharmacy costs ($3074 and $2899), medical costs ($2319 and $3704), and total health care costs ($6014 and $7023). However, insulin glargine was associated with significantly higher mean adjusted diabetes-related medical costs compared with insulin detemir ($1510 vs $707, respectively; P = 0.03), as well as significantly higher mean adjusted total diabetes-related health care costs ($3408 vs $2261; P = 0.03). Conclusions: In this managed care population of insulin-naive patients who initiated therapy with insulin detemir or insulin glargine, the daily insulin dose and glycemic control did not differ significantly between the 2 insulins. However, patients receiving insulin detemir incurred lower diabetes-related medical and total health care costs.