Medicaid Expansion and Utilization of Antihyperglycemic Therapies

Objective: Certain antihyperglycemic therapies modify cardiovascular and kidney outcomes among persons with type 2 diabetes mellitus (T2DM), but uptake in practice appears restricted to certain demographics. We examine the association of Medicaid expansion with use of and expenditures related to antihyperglycemic therapies among Medicaid beneficiaries.

Methods: We employed a difference-in-difference design to analyze the association of Medicaid expansion on prescription of non-insulin antihyperglycemic therapies. We used 2012-2017 National & State Medicaid data to compare prescription claims and costs between states that did (n=25) and did not expand (n=26) Medicaid by January 2014.

Results: Following Medicaid expansion in 2014, average non-insulin antihyperglycemic therapies per state/1,000 enrollees increased by 4.2%/quarter in expansion states and 1.6%/quarter in non-expansion states. For SGLT2i and GLP-1RA, quarterly growth rates per-1,000 enrollees were 125.3% and 20.7% for expansion states and 87.6% and 16.0% for non-expansion states, respectively. Expansion states had faster utilization and total spending growth in SGLT2i and GLP-1RA than non-expansion states. Difference-in-difference estimates for change in volume of prescriptions after Medicaid expansion between expansion vs. non-expansion states was 1.68 (1.09 to 2.26;P<0.001) for all non-insulin therapies, 0.125 (-0.003 to 0.25;P=0.056) for SGLT2i, and 0.12 (0.055 to 0.18;P<0.001) for GLP-1RA.

Conclusion: Use of non-insulin antihyperglycemic therapies, including SGLT2i and GLP-1RA, increased among low-income adults in both Medicaid expansion and non-expansion states, with a significantly greater increase in overall use and in GLP-1RA use in expansion states. Future evaluation of the population-level health impact of expanded access to these therapies is needed.