Cost, healthcare resource utilization, and adherence of individuals with diabetes using U-500 or U-100 insulin: a retrospective database analysis

Abstract

Objective:

To describe costs, healthcare resource utilization, and adherence of US patients receiving human regular U-500 insulin (U-500R), compared to patients receiving high-dose (>200 units/day) U-100 insulins (U-100) by subcutaneous injection for the treatment of diabetes.

Methods:

A retrospective analysis of data from Thomson Reuters MarketScan Research Databases (7/1/2008 to 12/31/2010). Difference-in-differences analyses were conducted on cost (medical, pharmacy, and overall costs) and on healthcare resource utilization variables (overall, diabetes-related, and non-diabetes-related medical visits). Adherence rates to the index insulins were assessed by proportion of days covered (PDC).

Results:

Seven hundred and eleven (19%) patients in the U-500R cohort and 1508 (6%) patients in the U-100 cohort met selection criteria. Propensity score matching resulted in 684 matched pairs. Mean change in annualized pharmacy costs was in favor of the U-500R vs the U-100 cohort (−$1258 vs $3345, a difference of −$4603, p < 0.0001). Mean overall cost increase in the U-500R vs the U-100 cohort was also lower ($1999 vs $9104, a difference of −$7105, p = 0.005). The proportion of patients with at least one coded hypoglycemic event during the 12-month post-index period was higher in the U-500R vs the U-100 cohort (17.1% vs 11.7%, p < 0.005), but neither hypoglycemia rate (2.73 vs 2.90 events per person) nor hypoglycemia-specific costs (mean $1669 vs $1543) were significantly different. No significant differences were noted between cohorts for change (post–pre) in any resource utilization category. PDC was greater in the U-500R vs the U-100 cohort (65.2% vs 39.5%, p < 0.0001).

Limitations:

Claims data are not as accurate as empirical evaluation by a clinician. Glycemic control data were not available for this analysis.

Conclusions:

In patients requiring high-dose insulin, treatment with U-500R vs high-dose U-100 insulins is associated with significant decreases in pharmacy and overall costs, slightly higher hypoglycemia incidence, no difference in hypoglycemia-specific costs or in resource utilization, and better adherence.

Keywords::

• U-500 insulin
• Insulin resistance
• Cost savings
• Utilization
• Medication adherence
• Hypoglycemia

Transparency

Declaration of funding

This work was sponsored by Eli Lilly and Company.

Declaration of financial/other relationships

E.L.E, P.W., B.H.C., J.X., D.C.H., and J.A.J. are employees of Eli Lilly and Company and own stock in Eli Lilly and Company. I.I. has received research support from Eli Lilly and Company, has served as a consultant for, and is on the speakers’ bureau of Eli Lilly and Company and Merck Sharpe Dohme. A.L.P. has served as a consultant and speaker for Eli Lilly and Company, Novo Nordisk, and Sanofi-aventis. R.C.H. has served as a consultant for and received research support from Eli Lilly and Company, and is on the speakers’ bureau of Eli Lilly and Company and Novo Nordisk. JME Peer Reviewers on this manuscript have no relevant financial relationships to disclose.

Acknowledgments

The authors thank Michelle Carey (PharmaNet/i3, part of the inVentiv Health Company) for assistance with the preparation of the manuscript.