More than half of seriously ill Medicare enrollees face financial hardships with medical bills, with prescription drug costs the leading problem, according to a study published Monday.

The study in the journal Health Affairs comes as legislation to curb drug costs for seniors languishes in Congress and the growing financial exposure of patients with insurance is getting more attention in the nation’s health care debates.

The survey findings were a surprise to researchers, since Medicare is considered relatively good coverage and most people have supplemental insurance to fill its gaps. After drug costs, the most often cited issues were hospital bills, ambulance rides and emergency visits.

“It points to a real issue that has gone under the radar,” said Tricia Neuman, a Medicare expert with the nonpartisan Kaiser Family Foundation who was not involved with the study and reviewed it for The Associated Press.

“Survey after survey shows that people are satisfied with Medicare, but this analysis shows that people with Medicare who have serious health problems can face very high out-of-pocket costs, and that’s an issue that hasn’t gotten much attention.”

All told, 53% of seriously ill Medicare patients said they had major trouble paying their medical bills.

More than a third reported using all or most of their savings to pay medical bills, 27% said they were contacted by a collection agency and 23% were unable to pay for basics such as food, heat and housing.

Nearly half (45%) reported emotional or psychological distress, and 1 in 4 said their medical costs had become a major burden on their families.

“We did not expect to see this extent of financial hardship in the Medicare population,” said Michael Anne Kyle, lead author of the study and a doctoral candidate at Harvard University.

She said lawmakers may need to devote more attention to the needs of Medicare beneficiaries with catastrophic costs.

“Out-of-pocket costs are very concentrated,” Kyle said. “The sickest population is also getting the biggest bills. Especially if you are sick over time, you are slowly draining your bank account.”

The study defined seriously ill people as those with a condition that over the past three years required two or more hospitalizations and visits to three or more doctors.

Included in the study were Medicare recipients 65 and older as well as younger beneficiaries who qualified for coverage because of disability. Over half had seen five to nine doctors in the past three years.

Among the most prevalent conditions were heart disease, cancer and diabetes. The cost of prescription drugs was the major hardship for a reported 30%.

Legislation to curb the costs of medicines for seniors has advanced this year in Congress, but it’s unclear if it can pass because the House and Senate remain far apart.

House Democrats want Medicare to directly negotiate prices for the costliest drugs — a nonstarter for Senate Republicans. However, there is widespread agreement on putting an annual out-of-pocket limit on drug costs for Medicare enrollees.

Although President Donald Trump wants a bill, the House impeachment inquiry has overshadowed efforts to move legislation. As a candidate, Trump had backed Medicare drug price negotiations. It’s uncertain if the White House will try to find a compromise now between the House and Senate positions.

A second study out Monday also called attention to seniors’ out-of-pocket costs. Focusing on people with traditional Medicare, the Kaiser Family Foundation estimated that the average enrollee spent $5,460 out of their own pocket for health care in 2016, counting premiums and medical services. That figure also included long-term care costs.

The average was lower — $4,519 — for people living in their communities and not in institutions.

The Health Affairs study was based on a 2018 national survey of people of any age who suffered from a serious illness. Researchers decided to go back and take a closer at the Medicare group because of the unexpectedly high degree of problems.

The margin of error was plus or minus 4.6 percentage points.

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