Effect of the Medicaid Expansion under the Affordable Care Act on Health Insurance Coverage, Health Care Access, Use, and Health Outcome for People with Disabilities

Abstract

Background: Compared with those without disabilities, people with disabilities have higher health care needs, service utilization, and expenditures. They are also more likely to experience delayed and unmet need for medical care. Health insurance facilitates access to health care, yet over 20% of working-age adults with disabilities did not have health insurance in 2013. The Medicaid expansion under the Affordable Care Act (ACA) broadens its eligibility criteria to cover all adults whose incomes are up to 138% of the federal poverty level. While a growing number of studies have examined the expansion effect on health care access and use for specific populations, little research has been done for people with disabilities. Objective: To examine the effect of the Medicaid expansion on health insurance coverage, health care access, use, and health outcome for working-age adults with disabilities. Analytical models: Difference-in-differences multinomial logistic models and linear probability models with state and year fixed-effects were used to estimate the effects. Participants: Adults with disabilities aged 18 to 64 years identified from the nationally representative Medical Expenditure Panel Survey - Household Components between 2007 and 2017 (N = 40,995). Intervention: The Medicaid expansion under the ACA. Main measures: 1) Insurance coverage: Medicaid, Medicare, Medicaid/Medicare dual eligible, private insurance, and uninsured; 2) Access: having a usual source of care, unmet medical care needs, and unmet prescription medicine needs; 3) Health services use: hospital emergency room visits, and office-based physician visits; 4) Health outcome: number of days missed from work due to health problems. Key results: Results from parallel trends assumption tests and falsification tests suggest an upper bound and a lower bound of the true treatment effect. The study found strong evidence of increased Medicaid coverage in the expansion states (3.2 to 5.0 percentage points), reasonably strong evidence of reduced private insurance (-2.5 to -2.2 percentage points), and some evidence of reduced uninsured rate (-3.7 percentage points from the main model). Results suggest that the increase in Medicaid coverage was due at least in part to Òcrowd-out,Ó namely a transfer from private insurance in expansion states. No statistically significant effects were detected for access, use and health outcomes. Conclusions: While findings suggest that the ACA was effective in expanding Medicaid coverage, the health care reform may have fallen short of removing other barriers to access such as low Medicaid physician fees. A more balanced approach is desired in national health reforms. Further research into health care access, use and health outcomes is needed when more data become available for the post-expansion period.