“The reasons for people continuing to use opioids are complicated and not always as simple as just pain after surgery,” Dr. Chad Brummett, a study author, and director of the pain research division in the University of Michigan Medical School’s Department of Anesthesiology, told Healthline.

‘Persistent opioid use’

The study, which was published April 12 in JAMA Surgery, found that about 6 percent of 36,000 adults continued to receive prescription opioids three to six months after surgery. The rates of “new persistent opioid use” were similar for people who had major or minor surgery. This was about 12 times more than the rate of long-term opioid use in a comparison group of similar people who didn’t have surgery during the study period.

Researchers also found that people who had certain conditions before surgery had a higher risk of long-term prescription opioid use. This included smoking, alcohol or substance abuse disorders, depression, anxiety, and arthritis or other chronic pain conditions. Around 50 million surgical procedures are performed in the United States each year. If the study’s findings hold for all patients, it would mean that each year about 3 million people who hadn’t used opioids recently would still be receiving these drugs months after their surgeries.

“This is an area that we have not focused enough on and certainly merits attention, given these high rates of new persistent use,” said Brummett. Experts say this study also addresses some misconceptions about prescription opioids.

“It’s a really important study because it’s one more piece of evidence that puts to rest this myth that people who become addicted to prescription opioids are people who were already addicted to something else,” Dr. Anna Lembke, psychiatrist and pain specialist at the Stanford University Medical Center, told Healthline.

Fueling the epidemic

This is not the first time that prescription pain killers have been implicated in fueling the opioid epidemic in the United States. A 2015 analysis published in the Annual Review of Public Health found that since the late 1990s, sales of prescription opioids have risen in parallel with opioid overdose deaths and opioid treatment admissions.

Opioids caused more than 33,000 deaths in 2015, according to the Centers for Disease Control and Prevention (CDC). Half of these deaths were due to prescription opioids, such as methadone, OxyContin, and Vicodin. But even after the CDC declared an opioid epidemic in 2011, doctors continued for several years to prescribe a significant amount of opioids to patients.

“It’s really only in the last year or so that we see some plateauing and some decrease,” said Lembke, “but not a substantial decrease.”

Two years ago, doctors wrote about 300 million opioid prescriptions. People in the United States use about 80 percent of the world’s opioid supply — yet the country only has 5 percent of the global population.

“We have no more need for analgesia than other high-income developed countries,” said Lembke, “and yet we consume vast amounts of opioids.”

Balancing risks, benefits

The JAMA Surgery study shows that opioids prescribed after surgery are contributing to the opioid epidemic, but that doesn’t mean these drugs don’t have their place in medicine.

“There’s no question that opioids are essential for the practice of modern medicine and are vital in managing acute pain, especially moderate to severe acute pain,” Dr. Itai Danovitch, chairman and associate professor of the Department of Psychiatry and Behavioral Neurosciences at Cedars-Sinai Medical Center, told Healthline.

“For most chronic pain conditions, opioids would not be a first or even a second-line medication,” said Brummett, “and really should be limited to very specific situations.”

And the downsides of opioids quickly accumulate when you are on them for months.

“There is a lot of evidence to show that taking opioids for 90 or more days leads to lots of risk factors and adverse medical consequences,” said Lembke. “One of which is addiction, but there are others — depression, constipation, hormonal imbalance, hypoxemia, accidental overdose death, and tolerance dependence withdrawal.”

Not everyone who uses opioids becomes addicted. But a 2015 study found that the risk of developing an opioid use disorder increased with both duration and dose — with duration having the biggest effect. Better pain relief. There are many points at which doctors can target the problem of long-term opioid use after surgery.

Additional “psychological support and education” before surgery can give patients clear expectations about the risks and benefits of opioids, said Lembke, and may reduce their need for opioids.

This is especially important for people with risk factors such as mental illness or a personal or family history of addiction. And it means educating doctors as well, a core mission of the Michigan Opioid Prescribing Engagement Network.

“We have to retrain physicians as to how they think about opioids but also to set fair expectations for patients about what’s to be expected,” said Brummett.

During surgery, non-opioid pain relief may also be available.

“Localized lidocaine infusions are just one example of innovative techniques that doctors are coming up with now to try to minimize the use of opioids,” said Lembke.

And after surgery, doctors can prescribe opioids in the smallest dose and duration that works for a patient. Surgeons also need to be alert for problems.

“If we begin to see patients going to two or three months of daily use, that should be a red flag,” said Lembke. “Not for stigmatizing the patient or shaming them or kicking them out of your practice, but for getting them additional support.”

This extra support might come from a pain management or addiction specialist. Or from a support group or the patient’s family physician. Danovitch also sees a need to break down the barriers between the physical health and mental health systems.

“We know that most people that struggle with chronic pain also have mental health issues — anxiety or depression or other adversity,” he said. “To achieve optimal health outcomes, they need to get both sets of services.”