Among about 36,000 patients, approximately 6% continued to use opioids more than three months after their surgery, with rates not differing between major and minor surgical procedures, according to a study published by JAMA Surgery.

According to researchers, little is known regarding the incidence and risk factors for persistent opioid use after surgery. For the study, researchers used nationwide insurance claims data set from 2013 to 2014 to identify US adults (ages 18 to 64 years) without opioid use in the year prior to surgery.

For patients filling a perioperative opioid prescription, the researchers calculated the incidence of persistent opioid use for more than 90 days among patients who had not used opioids previously, after both minor and major surgical procedures, and assessed data for patient-level predictors of persistent opioid use.

A total of 36,177 patients met the inclusion criteria, with 29,068 (80%) receiving minor surgical procedures and 7,109 (20%) receiving major procedures. The rates of new persistent opioid use were similar between the two groups, ranging from 5.9 percent to 6.5%. By comparison, the incidence in the nonoperative control group was only 0.4 percent. Risk factors independently associated with new persistent opioid use included preoperative tobacco use, alcohol and substance abuse disorders, mood disorders, anxiety, and preoperative pain disorders.

“New persistent opioid use after surgery is common and is not significantly different between minor and major surgical procedures but rather associated with behavioral and pain disorders. This suggests its use is not due to surgical pain but addressable patient-level predictors. New persistent opioid use represents a common but previously underappreciated surgical complication that warrants increased awareness,” the authors write.