The Centers for Disease Control and Prevention released new findings on Thursday that paint a somber picture of the nation’s opioid crisis. More than 42,000 Americans died in 2016 of opioid overdoses—a 28 percent increase over 2015.

There is no easy fix to this epidemic, and traditional approaches—such as limiting opioid prescriptions—thus far haven’t yielded improvements. In a paper published Thursday in the American Journal of Public Health, Northeastern drug policy expert Leo Beletsky and his colleagues advocate for a new approach—one that looks at the problem holistically and focuses on root causes.

“There are a lot of major problems, health and otherwise, in America. The over-reliance on opioids is one symptom of that,” said Beletsky, professor in the School of Law and Bouvé College of Health Sciences. “We see that not as the cause, but as a symptom of underlying issues.”

Those underlying problems include physical and mental health needs, economic stress, and unaddressed childhood trauma, Beletsky said. And they are all structural and social determinants of health that must be addressed in order to solve the complex problem of opioid abuse, he added. But so far, these factors have been largely ignored in efforts to quell the crisis.

“As with previous drug crises and the HIV epidemic, root causes are social and structural and are intertwined with genetic, behavioral, and individual factors,” the researchers said in their report. “It is our duty to lend credence to these root causes and to advocate social change.”

Educating healthcare providers on social and structural determinants of health is one promising part of the solution, Beletsky said.

“Instead, we’ve focused on cutting people off and trying to limit the supply of opioids,” Beletsky said. “The approach we’ve been taking is flawed and misguided when the real issues have to do with the reason people are using opioids in the first case. We need to focus on the root causes that have been ignored.”