At least 62 percent of all U.S. family bankruptcies result from medical expenses, reports a study released yesterday in The American Journal of Medicine—an increase from the 46 percent the reseachers found in 2001.

Analyzing data from 2,314 randomly selected 2007 (pre–mortgage meltdown) bankruptcy filings revealed that most of those who had claimed bankruptcy because of medical expenses had health insurance, owned homes, were in their mid-40s, and had middle class incomes.

High out-of-pocket expenses for those already insured and the loss of private insurance were the primary reasons for medical bankruptcy, report the study authors—many of whom are active members of Physicians for a National Health Program, a group that advocates for a single-payer system.

"Unless you're Warren Buffett, your family is just one serious illness away from bankruptcy," study author and associate professor of medicine at Harvard Medical School David Himmelstein said in a statement.

Although the proportion of medical costs as a major contributor to bankruptcy appears to be climbing, the total number of U.S. family bankruptcies actually fell by about half during that time period, Megan McArdle points out in her Atlantic Monthly column. So the total number of U.S. medical bankruptcies would have decreased from about 667,000 in 2001 to 451,000 in 2007.

Listen to a podcast about the study.

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