Overprescribing pain pills after surgery led to a surplus of 3.3 billion unused opioids in 2016, a glut of extra drugs that likely contributed to the United States’ burgeoning opioid crisis, according to a report released by the research firm QuintilesIMS Institute on Tuesday.
In addition to the potential for surplus pills to be misused by people they weren’t prescribed for, just having surgery in the first place increases a patient’s risk for continued opioid use and for developing an opioid addiction.
The report found that nearly 3 million Americans became persistent opioid users, meaning they continued to take the drugs for three to six months after their initial exposure to the drugs following surgery. That translates to 1-in-10 patients transitioning to long-term opioid use after surgery.
Some surgeries carry a higher risk for continued opioid use than others. Of the seven common surgeries the report analyzed, colectomy was the riskiest, with 18 percent of patients transitioning to longer-term use of the drugs. Ranking next was total knee replacements, with 17 percent of those patients continuing to take opioids after surgery. Lower-risk procedures included surgeries for hernias and hysterectomies, which each carried roughly a 7 percent risk of continued opioid use.
Those differences in risk didn’t surprise Dr. Eric Sun, an assistant professor anesthesiology, pain and perioperative medicine at Stanford University, who wasn’t connected to the report.
During a colectomy, surgeons remove part or all of the colon, and pain can vary, depending on how invasive the surgery is. “The bigger the incision, the more painful something ought to be,” Sun told HuffPost.
And as an anesthesiologist, “I can tell you knee surgeries tend to be very painful,” he said. “People complain about those.”
The new research tracks with Sun’s own work on the issue, including a study that examined chronic opioid use after 11 common surgeries and was published in JAMA Internal Medicine in 2016.
The study defined chronic opioid users as those who, after first few months of surgery, go on to fill 10 or more prescriptions or obtain more than a 120-day supply of the drugs within a year of the operation. Using those criteria, Sun and his coauthors found that total knee replacement and open gallbladder surgery carried the highest risk for chronic opioid use among those who hadn’t previously used the drugs (colectomy was not one of the procedures the researchers analyzed).
Sun’s study and the new report differed in the demographics most at risk for chronic opioid use after surgery. While the new report found that middle-aged women were particularly vulnerable, Sun’s report pinpointed elderly men as most in jeopardy.
Despite the addiction risk after surgery, many post-operation patients are suffering from legitimate pain, which doctors are obligated to treat compassionately.
“There’s a lot of other things you can give that can help, but at the end of the day, if someone is in a lot of pain, opioids are part of the mainstay,” Sun said.
“That’s sort of the next phase in all this research,” he added. “We know there’s a problem. The question is: What do you do about it? How do you keep these people from transitioning to long-term use?”
This article originally appeared on HuffPost.