Insulin Out-of-Pocket Cap of $35 Could Still Cause Economic Burden on Women, Racial, Ethnic Minorities

The Inflation Reduction Act of 2022 (IRA), which proposes capping insulin out-of-pocket costs at $35 for Medicare Plan D enrollees, may still perpetuate some health care access inequities, according to the authors of new research published in JAMA Network Open.¹ The results of the study showed that in 2019, 45.1% of study participants paid out-of-pocket costs of $35 or more. Medicare beneficiaries who were less likely to be eligible for the $35 cap include females, enrollees aged 64 years and younger, or ethnic and racial minorities.¹

“With a $35 per month cap on out-of-pocket insulin costs per product, savings could be substantial in some cases for people who use insulin,” wrote authors of a study conducted by partners at the Kaiser Family Foundation and Peterson Center on Healthcare.²

Insulin users who have a Medicare Part D plan would be able to access any insulin product—administered via vial or pen and of various types (rapid-acting, short-acting, intermediate-acting, ultra-long-acting, premixed) in a 30-day supply—and only pay the cap amount.²

Investigators aimed to understand how the out-of-pocket cap on insulin affected prescription satisfaction, adherence, and affordability among Medicare-insured insulin users. Then, they used the findings to understand potential access disparities.¹

The investigators studied the results of the Medicare Current Beneficiary Survey (MCBS), which collected patient-reported data on prescription satisfaction, adherence, and affordability. They also linked the answers from the survey with Medicare claims to understand how much patients were paying for their prescription drugs.¹

To estimate the association between these qualitative measurements and a $35 out-of-pocket cap on insulin, the team used different types of analyses, while also adjusting for age, sex, education, race, and ethnicity as well.¹

Their findings showed that prescription satisfaction decreased by 83.2% when insulin out-of-pocket costs were $35 or more per month. The results also showed that insulin users had a 61.3% lower likelihood of adhering to the prescript without the $35 cap.¹

The number of people eligible for the $35 cap more than doubled between 2006 and 2013, increasing from 21.7% to 44.6%; the percentage then stabilized in 2019. However, approximately the same number of people (49.7%) would be unable to afford the prescription when out-of-pocket costs were $35 or more each month.¹ A limitation of the study is the possibility of proxy response bias.¹

“These reports highlight the issues of insulin affordability and adherence and the urgent need to address them,” study authors wrote in the article. “Policy makers may consider strategies (eg, encouraging use of biosimilar insulin) to control future insulin costs. Attention should also be paid to expensive medications other than insulin, because patients with diabetes are increasingly being treated with these drugs.”¹

Reference

1. Li M, Yuan J, Lu K. Estimates of Insulin Out-of-Pocket Cap–Associated Prescription Satisfaction, Adherence, and Affordability Among Medicare Beneficiaries. JAMA Netw Open. 2023;6(1):e2251208. doi:10.1001/jamanetworkopen.2022.51208
2. Amin K, Claxton G, Rae M, et al. Out-of-pocket spending on insulin among people with private insurance. March 24, 2022. Accessed on January 20, 2022. https://www.healthsystemtracker.org/brief/out-of-pocket-spending-on-insulin-among-people-with-private-insurance/