Chronic opioid use increases after bariatric surgery

Chronic use of opioids among obese patients prior to bariatric surgery continues after bariatric surgery, and the dose has been shown to be greater postoperatively than preoperatively, according to a recent study in the Journal of the American Medical Association.

Marsha A. Raebel, PharmD, senior investigator at the Kaiser Permanente Colorado Institute for Health Research, Denver, and colleagues examined the electronic medical records and other clinical and administrative databases of 11,719 obese patients aged 21 years and older, who underwent bariatric surgery between 2005 and 2009 at 1 of 10 U.S. sites in the Scalable Partnering Network. Participating patients were evaluated 1 year before and 1 year after surgery.

Chronic opioid use was defined as having 10 or more prescriptions over 90 days or more or at least a 120-day total supply of medication sometime in the year prior to surgery. Some opioid use was defined as 1 to 9 prescriptions over 90 days or less than a 120-day supply.

In the year prior to their surgical procedures, the researchers found that 56% of the patients in the study reported no opioid use for pain management, 36% used some opioids, and 8% used opioids on a chronic basis.

Seventy-seven percent of the obese patients who exhibited chronic opioid use prior to surgery continued to use these medications chronically 1 year after their procedure. Chronic opioid use among these patients also increased by 13% the first year after surgery.

“Despite a lack of evidence supporting long-term effectiveness of opioids for chronic noncancer pain, long-term opioid use has increased recently,” Dr. Raebel said.

Prescription opioid consumption and mortality are correlated and opioid abuse, accidental overdose, and death have increased, with overdose deaths rising in 2010 for the 11th consecutive year in the United States, she added.

Observational studies show that bariatric surgery-related weight loss is associated with reduced knee pain and suggest association with decreased back pain, but evidence that bariatric surgery is associated with less hip or fibromyalgia pain is limited and conflicting.

“No published studies assess chronic opioid use in the bariatric surgery population, and information is needed on whether weight loss attained after bariatric surgery is associated with reductions in opioid use,” Dr. Raebel said. “Therefore, we undertook this study.”

There are limited options for pain management available to bariatric surgery patients because non-steroidal, anti-inflammatory medications increase the risk of gastric perforation, particularly after bariatric surgery and acetaminophen is less effective, according to Dr. Raebel.

“Given the increasing chronic usage of opioids we found after bariatric surgery relative to before surgery, it’s clear that we need to develop better pain management programs for patients who use opioids long-term following bariatric surgery,” she said.