Experts say it’s uncertain why this happens, but it’s a problem because people with mood disorders are more likely to abuse prescription drugs.

People with depression and mood disorders represent only 7 percent of the overall adult population in the United States.

But this group is being prescribed 51 percent of the opioids in this country.

It’s a statistic some experts find troubling, because people with mood disorders are at an increased risk of opioid abuse.

These are some of the key findings in a recent study published in the Journal of the American Board of Family Medicine. In the study, researchers analyzed a U.S. health survey with information on 51,000 adults.

These findings provide new context on the way these drugs are prescribed in a country in the midst of an opioid epidemic.

“The data suggests that there’s this large, disproportional prescribing to patients suffering from mental health disorders,” Dr. Brian Sites, the lead study author from Dartmouth-Hitchcock Medical Center, told Healthline. “That’s deeply concerning, because we already know that patients with these conditions are more vulnerable to opioid abuse, overdose, addiction, and even long-term use.”

Sites said it’s impossible to know the exact, specific causes of the problem.

However, he said the findings point to a need for further research as well as widespread, systemic changes.

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Researchers concluded that having a mental health disorder increased a person’s chances of receiving an opioid prescription by about twofold. This was true even when factors like age, sex, race, other health conditions, and varying pain levels were taken into account.

Additionally, the study indicated that 19 percent of Americans with mood disorders use prescription opioids, compared to just 5 percent in the general population.

“If you’re asking why they’re getting all these drugs, I don’t know the answer. The data is cross-sectional in nature, so you can’t prove a causation between mental illness and prescribing,” said Sites.

Sites told Healthline that there are all kinds of variables that influence whether or not a person receives an opioid prescription.

“It’s a function of four major factors. One is the patient, their background, and how they present themselves. Another is the physician, their background training, and their belief system. The third thing is the unique health system that they’re operating in. And the last thing is the overarching umbrella of social and regulatory policies that dictate these practices.”

Sites said it’s possible that the presence of a mental health disorder could increase a person’s chances of getting an opioid prescription — independent of the pain they’re experiencing.

“You can imagine a scenario where somebody with, for example, advanced anxiety would represent themselves differently from somebody who doesn’t have advanced anxiety,” he said. “The physician may, in perhaps an overcompensating move or an empathetic move, prescribe opioids to help with pain in a way that’s different than the physician would for somebody who doesn’t have that condition.”

Still, Sites stressed, more research is needed in order to determine the exact reasons that so many opioids are being prescribed to people with depression, anxiety, and other mood disorders.

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The United States prescribes 80 percent of the world’s opioids, but it has only 5 percent of the world’s population, Sites noted.

“We’ve created an opioid epidemic as a function of prescribing, and the Centers for Disease Control and Prevention says our pain is no better now than it was 15 years ago,” Sites said.

The general consensus in the medical community is that the United States is indeed in the midst of an opioid epidemic. But fixing the problem is no easy feat and will require significant cultural and systemic changes.

“To cut back, you have to have some change in the culture of prescribing. You have to change the expectations of patients around pain. You have to offer alternatives to opioids,” said Sites.

To accomplish all of this, said Sites, it’s necessary for social policy and political leaders to create an infrastructure that’s better equipped to diagnose and treat pain and mental illness.

He pointed out that it’s tough for many family doctors to provide the level of care that some patients need.

“It’s very hard to get access to both mental health and behavioral therapy,” he said. “It’s much easier to start writing prescriptions. So the way we reduce prescribing opioids is that we offer alternatives, and also that we understand what the goals of the therapy are.”

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