Senior citizens in the United States are, as a group, sicker than their counterparts in 10 other wealthy countries despite having near-universal health coverage provided by Medicare, a new report says.

Older Americans are also markedly more likely to have financial barriers to health care than the elderly in the other countries, according to the analysis published Wednesday in the journal Health Affairs.

The findings suggest that proposals to create a universal health coverage system in the United States by making a "Medicare-for-all" system would not necessarily lead to Americans of all ages achieving parity with their international counterparts in health outcomes and costs.

The report is based on the 2017 Commonwealth Fund International Health Policy Survey of Older Adults, which questioned 23,000 people.

In addition to the United States, it looked at the experiences of older adults in Australia, Canada, France, Germany, the Netherlands, Norway, Sweden, Switzerland and the United Kingdom.

At least one in every eight older adults in the Commonwealth Fund's survey reported having three or more chronic health conditions.

The United States had the highest rate, with 36 percent of the elderly Americans have three or more chronic conditions.

That contrasts with 17 percent in Australia, the Netherlands, Norway and Switzerland. Older adults in New Zealand had the lowest rate of multiple chronic conditions, at 13 percent.

Despite having Medicare, the federally run program that provides health coverage to primarily adults 65 years and older, those Americans often have trouble affording care when they need it.

A total of 23 percent of elderly Americans said that in the past year they had not gone to the doctor when they were ill, skipped a recommened medical test or treatment, or left a drug prescription unfulfilled because of cost, according to the Health Affairs report.

"In contrast, only 5 percent or fewer of older adults in France, Norway, Sweden and the United Kingdom reported these cost barriers," the report said.

Dr. David Blumenthal, president of the Commonwealth Fund, said "Medicare is the most popular [health coverage] program in the United States in terms of satisfaction of the population that is covered by it."

"The level of contentment is very high," Blumenthal said.

But despite that, he added, a signficant share of Medicare benficiaries "are underinsured," or do not have adequate financial coverage for their medical needs.

While Medicare does cover a large share of beneficiaries' health services, enrollees in the program are responsible for a share of out-of-pocket costs.