If Washington, D.C. legislators approve cuts to government health care, California’s rural counties are among those who will suffer most, according to a new report.

Those who live in the state’s rural counties—which are largely in Northern California—are more likely than urban residents to be enrolled in the low-income health program called Medi-Cal, according to the report released last Tuesday from the Georgetown University Center for Children and Families and North Carolina Rural Health Research Program.

Medi-Cal covers 28 percent of adults and 54 percent of children in California’s rural counties, researchers found. Meanwhile, in the state’s metro areas, 21 percent of adults and 44 percent of children are enrolled in the health program.

Before the federal Affordable Care Act and state reforms opened the gates of Medi-Cal to most low-income adults and children, a quarter of the state’s rural residents under age 65 were uninsured. But by mid-2015, that uninsured rate had fallen to 11 percent.

“The point for me here is the vote on the American Health Care Act would take us back to that world, where we did have one in four uninsured residents in our (rural) communities,” said Mike Odeh, director of health policy for Children Now, a statewide advocacy group.

The legislation, which the House of Representatives passed by a narrow margin in May, proposes cutting funding for low-income health programs. Five million Californians could lose health coverage if the act, which is awaiting Senate consideration, becomes law.

Rural Californian counties, with their larger percentages of Medi-Cal enrollees, would be most affected, according to the Georgetown report.

The nationwide report counted only California’s most rural counties: those with central urban areas that had no more than 50,000 people. Areas of the Central Valley or Inland Empire that also have wide swaths of farmland and open space weren’t counted as rural because those counties have more-populous cities.

These are the California counties listed as rural in the report: Alpine, Amador, Calaveras, Colusa, Del Norte, Glenn, Humboldt, Inyo, Lake, Lassen, Mariposa, Mendocino, Modoc, Mono, Nevada, Plumas, Sierra, Siskiyou, Tehama, Trinity and Tuolumne.

“California’s rural population is small—it’s only about 2 percent of the state,” Odeh said. However, the increases in health coverage in the last decade are “really important for kids,” he said. “We’ve made significant gains, even given the small population of our rural areas.”

Had the researchers included parts of the Central Valley as rural, for example, Odeh expects that the findings would have been similar. In Fresno County, the number of children with Medi-Cal increased from 53 percent in 2008 to 58 percent by mid-2015, according to data from the report.

“The percentage went up over time,” Odeh said, “so this isn’t an anomaly by any means.”

Low-income children who have health coverage “do better in school and have better education outcomes over time and better economic security over time,” he said.