The low-income adults who gained health insurance because their state expanded Medicaid under the Affordable Care Act (ACA) are healthier and more financially secure as a result, a new study in Health Affairs shows. The House-passed health bill, which effectively ends the ACA’s Medicaid expansion, would roll back these improvements.

The study, by Harvard University researchers, surveyed poor adults in the Medicaid expansion states of Arkansas and Kentucky, as well as in Texas, which has not expanded, since 2013. Their study is an update to a study that the authors released last year on those three states, which also showed larger coverage gains and improved outcomes in Medicaid expansion states. The authors chose these three states because, before the ACA’s coverage expansions took effect, the uninsurance rate among the population eligible for coverage under the Medicaid expansion was about 40 percent in each state.

Since Arkansas and Kentucky implemented the expansion, the uninsurance rate among this group has dropped to 12 percent in Arkansas and 7 percent in Kentucky, but to only 28 percent in Texas.

Also in Arkansas and Kentucky, Medicaid expansion fueled a 29 percent increase in the share of people with a personal doctor and a 24 percent increase in the share of people who received a checkup in the past year. With greater access to care came better outcomes: Medicaid expansion made people 42 percent likelier to say they’re in “excellent” health. (See graphic.) That’s consistent with other research showing Medicaid expansion has improved access to care and health outcomes.

In the same two states, Medicaid expansion has also made people more financially secure: the share of people having trouble paying their medical bills dropped by 25 percent, the study found. This, too, is consistent with research showing Medicaid expansion improves people’s financial well-being.

The evidence is clear: Medicaid expansion has made people healthier and more financially secure. The House bill would not only reverse these gains but would end Medicaid as we know it by converting virtually the entire program to a per capita cap or block grant. That would mean not only the 11 million people who have newly enrolled through the Medicaid expansion would lose their coverage but tens of millions of seniors, people with disabilities, children, and other adults who rely on Medicaid would be at risk of ending up uninsured or going without needed care.