Health

Chronic opioid dependence use increases after surgery, researchers find

People who undergo various types of common surgeries are at an increased risk of becoming chronic users of opioid painkillers compared with other patients.

Surgical patients need to be closely monitored to see how much opioid they are or aren't taking

Cataract surgery was one of the few operations not associated with an increased risk of chronic opioid use in a new U.S. study. (Beawiharta/Reuters)

People who undergo various types of common surgeries are at an increased risk of becoming chronic users of opioid painkillers compared with other patients.

Many patients who haven't previously taken opioids such as morphine, fentanyl or oxycodone are prescribed the pain medications after surgery. Opioid prescriptions have increased sharply in the past decade, particularly for noncancer pain, contributing to a crisis in the U.S. and Canada.

To find out how much surgery patients are at increased risk of taking the medication months after their procedure, researchers in California reviewed the records of more than 640,000 patients aged 18 to 64 who had 11 common operations and compared them to more than 18 million nonsurgical patients of similar age. 

The patients in the surgical group had procedures such as hip and knee replacements, gall bladder removals, C-sections,appendix removals and sinus surgeries.

Patients who didn't use an opioid before surgery were at increased risk, the investigators said in Monday's issue of the journal JAMA Internal Medicine.

"The risks range from about 1½ to five times depending on the surgery," said study author Dr. Eric Sun of Stanford University School of Medicine.

"Overall, the risk is pretty low, it was about less than one per cent for most of the surgeries we looked at," he added in a journal video.

Chronic opioid use was defined as having filled 10 or more more prescriptions or more than 120 days' supply of an opioid in the year after surgery, excluding the first 90 days after the operation, when use of painkillers is to be expected.

All of the surgeries were associated with an increased risk of chronic opioid use, except for cataract surgery, keyhole appendix removal, a sinus operation called functional endoscopic sinus surgery and transurethral prostate resection.

In general, men were more likely to be at increased risk than women, as were those 50 and older and people with a history of drug or alcohol abuse and use of benzodiapenes (often prescribed for anxiety) and antidepressants.

"Physicians should closely monitor their surgical patients to see how much opioid they are or aren't taking and just be aware that they may be at high risk for using opioids chronically," Sun suggested.

Non-drug options explored

In their paper, the authors said the results should not be taken as advocating that patients forgo surgery out of concerns for chronic opioid use. 

Canadian investigators have reported similar findings.

Some physicians are adopting alternatives to opioids, such as combinations of physiotherapy, meditation, acupuncture, and counselling, among other techniques for pain management, for patients who've had surgery.

The study's authors also listed use of regional anesthesia as another suggestion, particularly for those at higher risk.

They acknowledged they couldn't account for all factors that could affect the results, such as socioeconomic status.

Pain is often an indication for surgery. But they said even in the hip and knee replacements, the analysis considered patients whose pain wasn't enough to require chronic opioids before the procedure.