The risk of addiction to opioid painkillers after surgery significantly increases if a patient is depressed or has used pain medications prior to surgery, according to a pilot study at Stanford University. Researchers found that psychological risk factors were a better predictor of long-term opioid use after surgery than pain itself.
The study is being published in Anesthesia & Analgesia, the official journal of the International Anesthesia Research Society.
Over a hundred patients were enrolled in the study prior to undergoing breast cancer or joint replacement surgery. Patients were asked about their history of depression, previous use of opioids, and self-perceived risk of addiction.
After their surgeries, each patient’s pain levels were assessed daily, along with their use of prescribed opioids, such as morphine.
“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,” said lead author Dr. Ian Carroll.
About 6 percent of the patients were still taking opioids 150 days after their surgeries. The ones with three prior risk factors were more likely to be in that group:
- Patients who had use opioids for pain relief before their operations were 73% more likely to use them long term after surgery.
- Patients who rated themselves at risk of addiction were 53% more likely to use opioids long term.
- Patients with symptoms of depression had a 42% higher risk of long term use.
“Each of these factors was a better predictor of prolonged opioid use than postoperative pain duration or severity,” said Carroll, who added that preoperative risk factors were significant no matter what type of surgery the patient had.
The researchers say if just 6% of Americans who had surgery every year became long term opioid users, that would amount to 1.1 million new users annually.