MON-747 Trends In Insulin Out-of-Pocket Costs And Use Disparities, 2008 To 2021

Abstract E.S. Tremblay: None. S. Argetsinger: None. F. Zhang: Research Investigator; Self; GlaxoSmithKline, Pfizer, Inc.. D. Ross-Degnan: None. J. Wharam: None. Abstract Importance: Recent insulin out-of-pocket (OOP) cost reduction policies might be inefficient in failing to target patients who demonstrate cost-related underutilization, such as low-income members and those with high-cost sharing. High deductible commercial health plans with savings options (HDHP/SO) that require high medication cost sharing have become increasingly prevalent. Objective: To assess trends in insulin OOP costs and use among commercially-insured patients from 2008-2021 and determine trends in related disparities by health plan type and income level. Design: Retrospective time series design, including data from 2008-2021. Setting: A large, national commercial health insurance database with members in all US states. Participants: Commercially-insured insulin users aged 12-64 with at least one full enrollment year. Characteristics of interest for disparities analysis included income level (low- versus high-poverty zip code) and health plan type (HDHP/SO versus non-HDHP/SO plan). Main Outcome(s) and Measure(s): Insulin OOP costs and 30-day equivalent fills per year, adjusted for age, sex, and geographical area. Results: In 2008, adjusted mean annual insulin OOP costs were $221 (95% CI, 219 to 223) per non-HDHP/SO plan member and $313 (296, 329) per HDHP/SO member, increasing to $280 (277, 283) and $496 (485, 508), respectively, by 2014. OOP costs declined to $197 (194, 200) and $424 (412, 436), respectively, by 2021. We detected no disparities in insulin use by plan type until 2014 when HDHP/SO plan members had 0.17 (0.09, 0.25) fewer adjusted annual fills than non-HDHP/SO members, a disparity that generally increased until 2019 (-0.79 fills, -0.87, -0.72) before decreasing slightly by 2021 (-0.55 fills, -0.63, -0.46). Lower-income members consistently had fewer adjusted insulin fills than higher-income members across the study period. Conclusions and Relevance: After pronounced increases in insulin OOP costs from 2008-2014, HDHP/SO plan members exhibited persistent reductions in insulin use compared with non- HDHP/SO plan members. Income-related disparities in insulin use were present throughout. Findings suggest that insulin OOP cost reduction policies would be more efficient if they targeted HDHP/SO plan members and low-income patients. Monday, June 3, 2024