Out-of-Pocket Spending for Insulin by Medicare Beneficiaries After Monthly Caps
Authors' conclusion
In this cohort study, a $35 monthly insulin out-of-pocket cap was found to be associated with significantly lower insulin out-of-pocket spending, increased access to insulin, and decreased blood glucose levels among Medicare beneficiaries with T2D. These findings suggest federal cost-sharing policies could improve access and adherence to essential medications in diabetes and other chronic diseases.
Study context
- Population
- Medicare Part D beneficiaries with T2D in the IQVIA national longitudinal open claims database, 2019–2023; subset with linked ambulatory electronic medical recordsmedian quarterly cohort 1,393,402
- Participants
- 4.8 million beneficiaries
- Exposure
- Before vs after the $35 monthly insulin out-of-pocket cap
- Outcome
- Mean quarterly insulin out-of-pocket spending, mean daily units of insulin, mean HbA1c and incidence rates of severe hypoglycemia resulting in hospitalizations or ED visits
Methodological detailsinterrupted time-series analysis, segmented regression with generalized estimating equations, Analysis performed between January and July 2025
- Interrupted time-series analysis
- Segmented regression with generalized estimating equations
- Analysis performed between January and July 2025
Main finding
As reported in the abstract
Baseline mean quarterly insulin out-of-pocket spending
$192.66
95% CI $192.63-$192.68
Decline in 2021
$47.90
95% CI -$48.95 to -$46.84
Further decline in 2023
$58.59
95% CI -$59.91 to -$57.27
Observational data: associations, not effects.
Further findings
Mean daily insulin use
- Baseline
- 12.86 (95% CI, 12.86-12.87) units
- Increase in 2023
- 0.23 (95% CI, 0.15-0.31) units
Mean HbA1c (subset with linked electronic medical record data, n = 207 197)
- Baseline
- 7.28% (95% CI, 7.28%-7.28%)
- Decrease after 2023
- 0.06% (95% CI, −0.08% to −0.03%)
Safety
- Corresponding modest increases in rates of severe hypoglycemic events
Original publication
Composed by AI from the published abstract and checked against it. How Briefs are made →