One in five Americans have trouble paying medical bills, the Centers for Disease Control and Prevention said this week.

In the first half of 2012, 54.2 million people — or 20.3 percent of U.S. adults — lived in a household that had trouble paying its medical bills, the new government report found.

That’s down, though, from 21.7 percent during the first six months of the previous year, the agency said.

Among those having problems paying medical bills, 36 percent were uninsured, 14 percent had private coverage and 26 percent had public coverage.

Though the number has fallen slightly in the last year, that drop could mean more Americans aren’t struggling with bills because they’re skipping health care treatment (or coverage) altogether.

According to previous research from New York-based Hill & Knowlton Strategies, health care costs are keeping patients away from the doctor with about one in three saying it has made them put off medical treatment and skip or postpone a regular doctor’s visit.

In their research, 45 percent of consumers surveyed said they worried “a lot” about paying medical bills in the event of a catastrophic illness or accident, and 36 percent said they’re very concerned with paying for health insurance coverage. Cost was more worrisome than receiving the best medical care and having access to the latest, most innovative medical treatment.

CDC’s report was based on interviews with 155,321 people between January 2011 and June 2012.