A new report from the National Center for Health Statistics shows that millions of Americans still struggle to pay their medical bills, but the numbers are improving.

A new report from the National Center for Healthcare Statistics shows a slight improvement in the number of Americans who struggle to pay for medical care.

In the first six months of 2011, 21.7 percent of Americans, or 57.6 million people, reported having problems paying medical bills. In the first half of 2013, that number decreased to 19.8 percent, or 52.8 million people.

The numbers show that those under 18 are more likely to struggle with health bills—or be part of a family that struggles with these bills—than adults between the ages of 18 and 65. Still, the number of young people with medical-debt problems decreased from 23.7 percent in 2011 to 21.3 percent in 2013.

The survey defined “family” broadly, including households consisting of one person and, in some cases, households that comprised people who were not related or married to each other. Medical bills included those for doctors, dentists, hospitals, therapists, medications, equipment, nursing homes, and home care.

The report found that of those struggling to pay bills, 14.1 percent had private insurance, 24.7 percent had public coverage, and 34.3 percent had no insurance.

Now, under the Affordable Care Act (ACA), more than 7.1 million people have signed up for private healthcare coverage or Medicaid, potentially decreasing the number of Americans struggling with medical expenses over time. But not everyone is optimistic that the new law will reduce the nation’s high burden of medical bills.

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In 2013, an estimated 1.7 million Americans declared bankruptcy because of their medical bills, with California, Illinois, and Florida together accounting for one-quarter of those cases, according to an assessment by the number-crunching think tank NerdWallet.

Numerous studies have come to the conclusion that healthcare costs are the leading cause of bankruptcy in the U.S., but NerdWallet found that 56 million Americans under the age of 65 will have trouble paying medical bills this year.

Of them, 10 million—more than half the population of New York state—will be unable to pay for basic necessities such as rent, food, and heat because of their medical bills.

“While we are quick to blame debt on poor savings and bad spending habits, our study emphasizes the burden of health costs causing widespread indebtedness. Medical bills can completely overwhelm a family when illness strikes,” said Christina LaMontagne, vice president of Health at NerdWallet, in a statement.

And the new health insurance sign-ups under the ACA are not a cure-all. NerdWallet’s assessment found that 10 million Americans face bills they can’t pay, despite having year-round medical coverage.

“Insurance is no silver bullet,” LaMontagne said. “Even with insurance coverage, we expect 10 million Americans will face bills they are unable to pay.”

Besides being financially detrimental, medical debt is also bad for health, as more than 25 million adults will attempt to trim costs by forgoing necessary prescription medications.

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Chronic conditions account for the majority of the nation’s $2.87 trillion annual spending on healthcare.

And those who are diagnosed with cancer are 2.5 times more likely to declare bankruptcy than those who don’t have cancer, according to a study by researchers at the Fred Hutchinson Cancer Research Center in Seattle.

Analyzing data from people over the age of 21 and using records from of the U.S. Bankruptcy Court for the Western District of Washington, researchers found a strong link between the disease and the risk of financial distress.

“Although the risk of bankruptcy for cancer patients is relatively low in absolute terms, bankruptcy represents an extreme manifestation of what is probably a larger picture of economic hardship for cancer patients,” the researchers wrote in their study, which was published in the journal Health Affairs.

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