One in 10 cancer patients who took opioids for the first time after curative-intent surgery continued filling prescriptions a year later, researchers found in a retrospective review of insurance claims.
Among opioid-naive patients, the risk of new, persistent opioid use was 10.4% (95% CI 10.1%-10.7%), reported Lesly Dossett, MD, of the University of Michigan in Ann Arbor, and colleagues in the Journal of Clinical Oncology.
The risk of new, persistent opioid use was even higher — 15% to 21% — in patients receiving adjuvant chemotherapy.
“I was shocked to see how many of these patients — whose cancer we intend to cure — end up being long-term users,” co-author Jay Lee, MD, also of the University of Michigan, told MedPage Today. “I would hope that, since these patients have curable disease with surgery, once we take care of that, they would be cancer-free and not be on opioids long-term.”
About 6% to 8% of opioid-naive patients who have non-cancer procedures develop persistent opioid use, the researchers noted, but whether patients who undergo curative-intent cancer surgery had similar risk was unknown.
For this study, the researchers searched a national database of insurance claims for adult patients who had surgery for potentially curable cancer including breast, colorectal, cancer, esophageal, and hepato-pancreato-biliary/gastric cancer or melanoma. They selected patients who had lumpectomy, mastectomy, wide local excision, colectomy, rectal resection, pancreatectomy, liver resection, gastric resection, esophagectomy, and lung resection.
They analyzed records of 68,463 cancer patients 18 and older who had surgery from January 2010 to June 2014 and who filled an opioid prescription attributed to surgery.
The researchers included only patients with continuous insurance enrollment for 1 year before and after surgery, and excluded patients with hospital admissions over 30 days or a subsequent procedure within 180 days. They also excluded patients who were discharged to home hospice care or who died during their index hospitalization.
This study had two primary outcomes: new, persistent opioid use — defined as previously opioid-naive patients who filled an opioid prescription attributed to surgery and at least one additional opioid prescription 90 to 180 days after surgery — and daily opioid dose in the year after surgery, calculated every 30 days by dividing the quantity prescribed by the days supplied.
Opioid-naive patients were defined as those who filled no opioid prescriptions between 12 months and 31 days before surgery.
Three months after surgery, patients with new, persistent opioid use continued to fill opioid prescriptions with high daily opioid doses, equivalent to 6 tablets per day of 5-mg hydrocodone. Daily opioid doses remained at this high level even 1 year after surgery.
Patients with new, persistent opioid use were significantly more likely to have received adjuvant chemotherapy and to have filled preoperative opioid prescriptions, but initially were prescribed the same quantity of opioids, about 40 tablets of 5-mg hydrocodone.
Age, sex, neo-adjuvant chemotherapy or radiation, and insurance type also had no consistent association with new, persistent opioid use.
Persistent postsurgical pain may be one reason patients continued taking opioids, the authors noted. Neurotoxicity from adjuvant chemotherapy and radiation also may play a role, as might curative-intent chemoradiation, aromatase inhibitors and granulocyte colony-stimulating factors. Another contributing element might be uncoordinated prescribing from multiple providers.
Prescribing guidelines need to be changed and physicians need to take a more active role in counseling patients about postoperative opioid use, the researchers concluded.
“For cancer patients, pain is a little more complex,” Lee said. It’s not the same as a routine appendectomy, he noted; many cancer patients will need chemotherapy or radiation and those treatments can have painful side effects.
But if a cancer patient doesn’t need additional therapies, he would expect them to be opioid-free in 2 weeks: “Once it goes beyond that, we have to ask, ‘what’s causing patients to have persistent pain, and are opioids really the right treatment?’ It’s very unusual that opioids would be the right treatment for long-term pain.”
The study sample was selected to represent, as much as possible, patients likely to be disease-free after surgery, not those with advanced metastatic disease, Lee emphasized.
“As we get better with treating cancer, we’re going to have more survivors and patients who are free from cancer,” he said. “It becomes much more important that survivors have a good quality of life. And that means making sure they are not chronically on opioids and their other needs are met.”
In their report, Dossett and colleague listed a number of limitations to the analysis, including lack of data on indications for opioids, usage of non-opioid pain medications, prescribers’ specialties, or presence or extent of post-operative complications.
This research was supported by a National Research Service Award, the National Institute on Drug Abuse, and the Michigan Department of Health and Human Services.
Several authors reported relationships with Neuros Medical, Merck, and Anesthesia Associates of Ann Arbor.
F. Perry Wilson, MD, MSCE Assistant Professor, Section of Nephrology, Yale School of Medicine and Dorothy Caputo, MA, BSN, RN, Nurse Planner