EBRI Issue Brief

The Impact of Expanding Pre-Deductible Coverage in HSA-Eligible Health Plans on Medication Adherence

Jun 27, 2024 21  pages


IRS Notice 2019-45 allows health savings account (HSA)-eligible health plans the flexibility to cover 14 drug classes and other health services used to prevent the exacerbation of chronic conditions prior to meeting the plan deductible. In this Issue Brief, we used claims data to quantify the effect of expanding pre-deductible coverage on medication adherence among enrollees with certain chronic conditions. We found some evidence that expanding pre-deductible coverage in HSA-eligible health plans increased medication adherence in 2022, but not earlier.

Key Findings:

  • By 2022, there was evidence of a rebound in medication adherence. We found that the percentage of enrollees with diabetes using insulin increased 4 percentage points, and the percentage of enrollees with heart disease or diabetes using statins increased by 1 percentage point. While the magnitude of the effect may seem small, it is important to remember that when medication adherence fell as a result of the introduction of an HSA-eligible health plan, the magnitude of the declines was relatively small as well. Furthermore, the implied out-of-pocket elasticities of demand are closely aligned with previously published estimates.


  • The lack of a large increase in medication adherence may also be due to the fact that adherence rates were already relatively high, averaging 77 percent to 89 percent, with the exception of inhaled corticosteroids, which are often used as a rescue medication and not necessarily filled in a way that would suggest that an enrollee was adherent.

Our findings may be influenced by the ways in which employers implemented changes in response to the IRS notice. First, while the overall employer response to the notice seemed overwhelming, with three-quarters reporting that they expanded pre-deductible coverage for at least one of the 14 services, we would expect the largest impact on medication adherence for diabetes medications and beta blockers, as 66 percent and 54 percent added pre-deductible coverage for those services, respectively. Less than one-half added pre-deductible coverage for inhaled corticosteroids (43 percent), angiotensin-converting enzyme (ACE) inhibitors (39 percent), statins (38 percent), selective serotonin reuptake inhibitors (SSRIs) (35 percent), and anti-resorptive therapy (29 percent).

Similarly, it is not a surprise that the magnitude of the effects is small, as the majority of employers substituted copayments and/or coinsurance for deductibles when they expanded pre-deductible coverage. Whether employers moved from deductibles to no cost sharing whatsoever varied by the different medications. Statins were most likely to be covered in full, with 40 percent of employers reporting that they did not require any cost sharing as a result of the IRS notice, which may explain why statins were one of the two medications that experienced a rebound in adherence. In contrast, only one-quarter of employers exempted ACE inhibitors, SSRIs, or inhaled corticosteroids from any cost sharing.

The fact that we did not see a change in adherence for most of the medications examined is not surprising. Since 2021 was the first year that many employers expanded pre-deductible coverage, it may take time for enrollees to learn that their health plan has changed coverage for certain preventive services. They may not be aware of the change in plan design, despite employers’ best efforts to inform enrollees of a plan design change that is considered an improvement in benefits.

This study was conducted through the EBRI Center for Research on Health Benefits Innovation (EBRI CRHBI), with the funding support of the following organizations: Aon, Blue Cross Blue Shield Association, Johnson & Johnson, JP Morgan Chase, and PhRMA.