Impact of Insulin Copay Cap Legislation on Savings, Adherence, and Utilization Among Health Plan Medicare Beneficiaries
by Darryl K. Monroe II, PharmD, MBA, Agata Siwak, PharmD, MSBA, Marleen K. Wickizer, PharmD, AE-C, CDCES, Robert Topp, PhD, RN
Abstract:
Purpose: The purpose of this study was to determine the effect of the Inflation Reduction Act (IRA) on member copayments for insulin between 2022 and 2023, while also identifying relationships between copayments for insulin and adherence, average income, gender, and utilization of insulin and GLP-1 agonists.
Methods: A retrospective claims analysis was conducted for Medicare beneficiaries of a single health plan; members were included if they had at least two paid insulin claims between the periods of January 1, 2022, to June 30, 2022, and January 1, 2023, to June 30, 2023. Adherence was measured using proportion of days covered. Members were categorized into an income range by their zip code based on the 2020 US Census data.
Results: There were 71 members in the 2022 cohort and 59 in the 2023 cohort. After implementation of the IRA, there was a statistically significant decrease in the average of member copayments for insulin between 2022 ($68.15) and 2023 ($54.34) (p < 0.001). Although the overall ANOVA model was not significant, post hoc comparisons indicated a trend in which adherence in the ≤ $60,000 income group was lower than both the $70,000-$79,999 (p = 0.01) and $80,000-$89,999 (p = 0.04) income groups. Between the years, GLP-1 utilization significantly increased (p = 0.03).
Conclusions: The insulin copay legislation significantly lowered insulin copayments for Medicare beneficiaries of the studied health plan, and a trend was identified between members’ income and their level of adherence. Despite IRA implementation, GLP-1 agonist utilization continued to increase.
Keywords: Insulin, GLP-1 agonist, Inflation Reduction Act, IRA, copayment, Medicare, managed care pharmacy
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2024 November/December Table of Contents
Abstract:
Purpose: The purpose of this study was to determine the effect of the Inflation Reduction Act (IRA) on member copayments for insulin between 2022 and 2023, while also identifying relationships between copayments for insulin and adherence, average income, gender, and utilization of insulin and GLP-1 agonists.
Methods: A retrospective claims analysis was conducted for Medicare beneficiaries of a single health plan; members were included if they had at least two paid insulin claims between the periods of January 1, 2022, to June 30, 2022, and January 1, 2023, to June 30, 2023. Adherence was measured using proportion of days covered. Members were categorized into an income range by their zip code based on the 2020 US Census data.
Results: There were 71 members in the 2022 cohort and 59 in the 2023 cohort. After implementation of the IRA, there was a statistically significant decrease in the average of member copayments for insulin between 2022 ($68.15) and 2023 ($54.34) (p < 0.001). Although the overall ANOVA model was not significant, post hoc comparisons indicated a trend in which adherence in the ≤ $60,000 income group was lower than both the $70,000-$79,999 (p = 0.01) and $80,000-$89,999 (p = 0.04) income groups. Between the years, GLP-1 utilization significantly increased (p = 0.03).
Conclusions: The insulin copay legislation significantly lowered insulin copayments for Medicare beneficiaries of the studied health plan, and a trend was identified between members’ income and their level of adherence. Despite IRA implementation, GLP-1 agonist utilization continued to increase.
Keywords: Insulin, GLP-1 agonist, Inflation Reduction Act, IRA, copayment, Medicare, managed care pharmacy
Download PDF
2024 November/December Table of Contents