As if student loans weren't enough, millennials also rack up the most medical debt

Older people might need more costly medical treatments, but young people have more bills in the collection stage, according to the research study, “Unlike Medical Spending, Medical Bills In Collections Decrease With Patients’ Age,” published in Health Affairs.

The researchers used U.S. Census information paired with anonymous credit report data on more than four million Americans to study the age profile of people whose medical bills were sent to a US collections agency in 2016, and found that the average size of medical debt fell nearly 40 percent from patients age twenty-seven to sixty-four.

Related: Pay the medical bills or save for retirement?

Older Americans are better able to pay their medical bills because they likely have more health insurance coverage and higher incomes to pay any deductibles, according to the study.

“However, the frequency of medical collections — that is, the proportion of people with a collection by age — was less closely tied to insurance coverage rates,” the authors write. “A potential explanation is that most medical collections were relatively modest in size, with more than half of them less than $600 annually. As a result, medical collections could still occur under typical insurance plans.”

Indeed, insurance “isn’t a failsafe,” according to Axios.

“Because most unpaid bills aren’t catastrophically large, they’re well within many people’s deductibles,” Axios writes. “So, younger or lower-income people with high-deductible plans could still have to face a collection agency if they need to use their coverage.”

About 16 percent of consumers have an unpaid medical bill that has been referred to a collection agency. The locations that had more people with medical debt – and higher amounts of debt – were lower-income areas that had more uninsured individuals, particularly uninsured younger people, according to Census data.

On the other end of the spectrum, individuals 65 years and older have costlier bills, but have hardly any medical debt because they can rely more on Medicare to help cover costs, according to the study.

Kenneth Thorpe, who leads the Department of Health Policy and Management at Emory University in Atlanta, told PBS that the rate of people who say they have no health insurance drops about 30 percent between ages 27 and 45.

“We need to redouble our efforts to try to find ways to make health insurance more attractive and more affordable, particularly under the age of 44,” Thorpe says.

But even with insurance, chronic conditions like hypertension and diabetes can increase medical costs, so policymakers need to tackle these issues first, he adds.