A variety of factors unrelated to pain — such as depression, prior use of pain medications and a high perceived risk of addiction — increases the chance that a person will continue using strong pain-relieving drugs long after surgery, according to a new study.
“Each of these factors was a better predictor of prolonged opioid use than postoperative pain duration or severity,” according to the new research, led by Ian Carroll, M.D., of Stanford University.
For the study, researchers analyzed factors linked to long-term use of strong pain medications in 109 patients having various types of surgery (breast cancer surgery, chest surgery, or joint replacement). Before the procedure, the patients were scanned for a number of factors that could potentially affect their use of pain-relieving drugs.
After surgery, the patients received regular assessments of their use of opioid medications — morphine and related drugs.
Five months after surgery, six percent of patients still had a prescription for opioid drugs. Patients who were given opioids for pain relief before surgery — whether prescribed or otherwise — were 73 percent more likely to still be taking these drugs at follow-up.
Long-term opioid use was also higher for patients who, before surgery, rated themselves at higher risk of becoming addicted.
These risk factors — depression, prior use of pain medications and a high perceived risk of addiction — were better predictors of long-term opioid use than the severity or duration of pain after surgery, regardless of the type of surgery.
“As patients recover from surgery, they face an ongoing choice either to continue taking prescribed opioids or to stop opioids and undertake non-opioid pain treatment,” Carroll and colleagues said.
Few studies have looked at the factors linked to the continued use of strong pain medications after surgery. In patients with chronic pain, taking opioids is more related to psychological distress and substance abuse than to pain intensity.
The researchers point out that, if the six percent rate of long-term opioid use applied to the average 17.6 million patients having surgery every year, there would be 1.1 million new opioid users in the population annually.
Carroll and coauthors emphasize that some of the long-term opioid use in their study could have been legitimate. However, the results bring up concerns about the “disconnect” between the non-pain-related risk factors and the reason (pain relief) for which the drugs are prescribed.
Source: Anesthesia & Analgesia