“There has been increased attention for healthcare providers to try to relieve pain,” said Marjorie Wang, MD, MPH. “As a result, opioid prescribing has escalated, even in the face of limited evidence for long-term efficacy.”

Dr. Wang and her colleagues conducted a retrospective cohort study of 211 adult patients (172 of whom were available at 12-month follow up) enrolled in a prospective, nonrandomized study of health outcomes after elective cervical spine surgery for degenerative changes at a single center. Prior to surgery, 44 percent of the patients used opioids, and 56 percent did not.

There were no significant differences between cohorts in the type of surgery performed or in the number of levels treated. However, the proportion of patients with myelopathy was lower in the cohort of patients who used opioids before surgery. That cohort also included a higher proportion of patients with obesity (defined as body mass index [BMI] greater than 29.9).

In addition, preoperative Neck Disability Index [NDI] and SF-36 physical function and bodily pain subscales were significantly worse in the cohort of patients who used opioids prior to surgery, compared to the cohort of patients who had not used opioids.

Similar improvements
“We saw similar improvements in both NDI and SF-36 physical function and bodily pain subscales across both groups,” said Dr. Wang. “In fact, there was even a trend for the preoperative opioid cohort to report larger improvement in their NDI scores. And more than 70 percent of each cohort reported satisfaction with meeting expectations for pain relief after surgery.”

At 12-month follow-up, however, 50.7 percent of patients who used opioids before surgery continued to use them; among patients who had not used opioids before surgery, 17.5 percent were using the drugs at 12-month follow-up. Overall, nearly a third of patients were still using opioids a year after surgery.

According to Dr. Wang, predictors of continued opioid use included:

• any preoperative opioid use
• duration of symptoms for more than 9 months before surgery
• tobacco use
• higher score on the Quan Charlson comorbidity index
• lower preoperative SF-36 physical function score

“Overall, patients using opioids before surgery report worse baseline NDI and disability scores, and 1 year after surgery, about half continued to use opioids,” explained Dr. Wang. “This is a significant difference compared to patients who did not use preoperative opioids.

“However, both groups reported similar improvements in their physical function and bodily pain, in satisfaction, and in meeting expectations for pain relief.”

Dr. Wang suggested that, based on the study data and because both groups reported similar improvements, reasons for continued opioid use need to be further explored.

Study limitations
In noting limitations of the study, she pointed to the fact that opioid use was obtained from electronic medical records, without pharmacy verification for refills. In addition, the study did not examine opioid use duration or dosing prior to surgery, there was no structured coordination of pain management, and the decision to prescribe opioids could have come from a variety of providers.

“I believe opioid use needs to be followed over a longer time period, and the reasons for continued opioid use need further investigation,” she concluded.

Dr. Wang presented data from her study, “Predictors of 12-Month Opioid Use After Elective Cervical Spine Surgery for Degenerative Changes,” at the 2013 annual meeting of the North American Spine Society.

Dr. Wang’s coauthors include: Andrew M. Lozen, MD; Erin E. Krebs, MD, MPH; Purushottam W. Laud, PhD; Ann B. Nattinger, MD, MPH.

Disclosure information: Dr. Wang—American Association of Neurological Surgeons/Congress of Neurological Surgeons Joint Section on Disorders of the Spine and Peripheral Nerves; Drs. Lozen, Krebs, Laud, and Nattinger—no information available.

For more information on opioid use in orthopaedics, see “Prescription Painkillers and Sex” and “Medication Safety: An AAOS Priority.”

Peter Pollack is electronic content specialist for AAOS Now. He can be reached at ppollack@aaos.org

Bottom Line

• This small study focused on opioid use by patients after elective cervical spine surgery.
• Although all patients reported similar improvements in pain and function, and 70 percent reported satisfaction with their results, more than half of those who used opioids prior to surgery were still using them a year later.
• In addition, nearly one in five patients who had not used opioids before surgery were using them a year after surgery.