Not all of the costs of health-care debt can be measured in dollars and cents; Twenty-two percent of U.S. adults with medical debts skip food because their debts prevent them from buying. One in five skip education, and 18% are prevented from paying their rent or mortgage. Meanwhile, 44% of respondents say medical debt harmed their credit score, and 42% say their bills have been sent to a debt collector.

Americans with medical debt don't see a quick resolution to their struggles. One in three believe it will take longer than two years to pay off their debt. In this environment, 37% are extremely or moderately concerned that medical debt will affect their financial health. A similar number, 33%, are extremely or much stressed by their debt.

Almost half of Americans with medical debt say they tried to negotiate their debt. The largest number spoke with their health care providers (31%). Twenty-one percent negotiated with a debt collection agency, and 12% with their insurance company.

"Folks should understand their explanation of benefits and get everyone — bill collectors, insurance firms and your doctor — on the same page," said Jeff Smedsrud, cofounder of HealthCare.com and board member of RIP Medical Debt. "Double-check your statement for accuracy and remember you may be able to negotiate a discount."

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