In news profiles of the victims of the opioid epidemic, the narrative is familiar: a person gets a legal prescription for an opioid from their doctor after throwing out their back, then accidentally fall into a life of addiction.
Dr. Michael Barnett, assistant professor of health policy and management at the Harvard T. H. Chan School of Public Health, wanted to scrutinize stories like these with a scientist’s lens. “What’s the beginning of this transition to chronic opioid use?” he wondered. “How does that happen?”
In a new study published in the New England Journal of Medicine, Barnett and his team found that doctors, indeed, have a lot to do with who starts chronically taking opioids. And which doctor you happen to see may help determine whether or not you develop a habit.
Using Medicare insurance claims data, the research team looked at people mostly over age 65 who came into the emergency room. The researchers only considered those who hadn’t filled a prescription for opioids in the past six months, in order to eliminate those who were chronic opioid users.
They also ranked emergency physicians within the same hospital as high prescribers of opioids or low prescribers.
“There’s very little guidance on how and when to prescribe opioids to patients,” Barnett says. Therefore, he and his team thought they’d find that doctors prescribe opioids at different rates.
But they saw much more variation than they expected. Doctors in the top 25% of prescribers prescribed an opioid for nearly 1 in 4 of these emergency department patients, while in the bottom group, physicians prescribed patients opioids only 7% of the time. In other words, patients who saw a high prescriber were three times more likely to get an opioid prescription.
To see if this made any real difference in the lives of patients, they looked at which patients were still filling opioid prescriptions months down the line: a sign of long-term use. They found a 30% difference simply based on whether that patient had seen a high prescriber or a low prescriber.
“These are folks who come in for acute pain, and they don’t really get to choose the doctor they see,” Barnett says. Yet for every 48 of these emergency department patients prescribed an opioid, one became a long-term user.
The study wasn’t designed to evaluate whether these long-term users were addicted or dependent on opioids, though Barnett says it “probably does represent some form of dependence for a lot of those patients.”
This problem of overprescribing opioids—and, according to other research, failing to warn patients about the risks of dependence and overdose—isn’t unique to emergency doctors. Physicians in other specialties, like internal medicine and primary care, prescribe even more opioids, Barnett says. “The whole medical community has a responsibility for this.”
More research is needed to develop guidelines for safe and effective treatment of pain with opioids, Barnett says. “I think it’s a warning shot to doctors about understanding the risks of these medications and communicating them much more clearly—both to each other during training, as well as the patients.”
The results also highlight the potential dangers of opioids for anyone prescribed them. “There is a damaging effect of even that first initial prescription you get,” Barnett says.
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Write to Mandy Oaklander at mandy.oaklander@time.com