Patient characteristics, drug adherence patterns, and hypoglycemia costs for patients with type 2 diabetes mellitus newly initiated on exenatide or insulin glargine

ABSTRACT

Objective: Examine real-world effectiveness and hypoglycemia cost burden in patients with type 2 diabetes newly initiated on exenatide or insulin glargine.

Design and methods: Retrospective cohort study describing patient characteristics, drug adherence patterns, and 1-year hypoglycemia rates with associated costs using an administrative claims database. Adult subjects with type 2 diabetes had an initial claim for exenatide or insulin glargine between May 1, 2005 and June 30, 2007, and had continuous eligibility for ≥ 6 months pre- and ≥ 12 months post-initiation.

Results: The exenatide cohort (n = 3262) was 53 ± 10 years (±SD); 54% female. The insulin glargine cohort (n = 3038) was 56 ± 12 years; 41% female. The mean Deyo-Charlson comorbidity index score was 1.45 for exenatide versus 1.82 for insulin glargine (p < 0.001). Baseline OAD use rates for exenatide and insulin glargine, respectively, were 77% versus 69% metformin; 47% versus 65% sulfonylurea; 50% versus 49% thiazolidinedione; 56% versus 60% multiple OAD. For patients with two or more pharmacy claims for exenatide or insulin glargine, the 12-month medication possession ratio (MPR) was 68 ± 29% for exenatide and 58 ± 28% for insulin glargine (p < 0.001). MPR ≥ 80% was higher for exenatide (p < 0.001) and fewer patients discontinued therapy (p < 0.001). The probability of a hypoglycemic event was significantly lower for exenatide (p < 0.005), resulting in lower associated annual costs.

Conclusions: This study provides the first real-world observational comparison of type 2 diabetes patients newly initiated on exenatide or insulin glargine. Exenatide patients had a lower comorbidity burden, better drug adherence, and a lower rate of hypoglycemic events with associated costs. Retrospective database analyses examine medical care utilization in large populations using a relatively inexpensive and expedient approach. However, data are only representative of a commercial health-care plan with limited information on multiple variables usually collected during clinical trials.

Key words: :

• Exenatide
• Health outcomes
• Hypoglycemia
• Insulin glargine
• Medical possession ratio
• Obesity
• Refill gap analysis
• Type 2 diabetes

Acknowledgments

Declaration of interest: This study was funded by Amylin Pharmaceuticals Inc, San Diego, CA, USA and Eli Lilly & Co, Indianapolis, IN, USA. R. F., L. L. N., M. W., and B. S. are employees and stockholders of Amylin. D M. is an employee and stockholder of Lilly. Data extraction from the HealthCore Integrated Research Database was carried out by HealthCore Inc, Wilmington, DE, USA. R. Q. and R. W. are employees of HealthCore.

Notes

* Data in this paper were presented at the Annual meeting of the American Diabetes Association, June 2008; and at the Annual meeting of the European Association for the Study of Diabetes, September 2008