Effects of the Medicaid expansion under the Affordable Care Act on health insurance coverage, health care access, and use for people with disabilities.

Background: People with disabilities have higher health care needs, service utilization, and expenditures. They are also more likely to lack insurance and experience unmet need for medical care. There has been limited research on the effects of the Affordable Care Act Medicaid expansion on people with disabilities.

Objective: To examine the effects of the Medicaid expansion on health insurance coverage, access, and service use for working-age adults with disabilities.

Methods: A retrospective study using 11 years (2007-2017) of data from the Medical Expenditure Panel Survey - Household Components, linked to Area Health Resource Files and Local Area Unemployment Statistics (N = 40,995). Difference-in-differences multinomial logistic and linear probability models with state and year fixed-effects were used to estimate the effects.

Results: We found strong evidence of increased Medicaid coverage in expansion states (3.2 to 5.0 percentage points), reasonably strong evidence of reduced private insurance coverage (-2.2 to -2.5 percentage points), and some evidence of reduced uninsured rate (from no effect to -3.7 percentage points). Results suggest that the increase in Medicaid coverage was due at least in part to the "crowd-out" of private insurance in expansion states. No statistically significant effects were detected for access and use outcomes.

Conclusions: Findings suggest that state Medicaid expansions led to an increase in Medicaid coverage and a decrease in private insurance coverage as well as the uninsured. However, no evidence was found for health care access and use outcomes. Further research into access and use is needed when more data become available for the post-expansion period.