Five percent of Americans account for almost half of all U.S healthcare expenses, according to a new federal analysis.

The Agency for Healthcare Research and Quality also reported this week that about half of the U.S population spends little to nothing on healthcare, but 1 percent accounted for 22 percent of costs in 2009.

Federal officials said the uneven distribution of healthcare costs is a significant issue, as Congress reviews healthcare reforms.

“As policymakers consider various ways to contain the rising costs of healthcare, it is useful to examine the patterns of spending on healthcare throughout the United States,” the agency report said. “Actual spending is distributed unevenly across individuals, different segments of the population, specific diseases, and payers.”

The AHRQ report found:

• The 15 most expensive health conditions account for 44 percent of total healthcare expenses.

• Patients with multiple chronic conditions cost up to seven times as much as patients with only one chronic condition.

• The 5 percent of Americans who account for 50 percent of healthcare expenses cost about $36,000 each.

• Of patients who accounted for the top 10 percent of healthcare expenses in 2008 and 2009: 60 percent were women; 40 percent were 65 or older; 80 percent were white.