Opioids vs Nonopioid Medications for Chronic Back, Knee, and Hip Osteoarthritis Pain
Patients with chronic back pain or knee or hip osteoarthritis pain were recruited from Veterans Affairs primary care clinics.
Opioids and nonopioid analgesics were found to provide similar improvements in pain-related function over a 1-year period in patients with chronic back pain or knee or hip osteoarthritis pain, according to a study published in the Journal of the American Medical Association.
For this randomized trial (Clinicaltrials.gov identifier: NCT01583985), a total of 240 patients with chronic back pain or knee or hip osteoarthritis pain were recruited from Veterans Affairs primary care clinics.
Investigators randomly assigned patients to receive opioid therapy (n=120) or nonopioid analgesics (n=120).
In the opioid therapy group, patients were initiated on immediate-release opioids (eg, morphine, oxycodone, or a hydrocodone/acetaminophen combination; step 1). Step 2 consisted of morphine sustained action and oxycodone sustained action. Transdermal fentanyl was used in step 3. Participants in the nonopioid medication group were started on acetaminophen and nonsteroidal anti-inflammatory drugs (step 1), followed by adjuvant oral drugs (eg, amitriptyline, gabapentin) and topical analgesics (eg, lidocaine; step 2). Pregabalin, duloxetine, and tramadol were used in step 3.
Improvements in pain-related function over a 1-year period as assessed by changes in the Brief Pain Inventory [BPI] interference scale were the study's primary outcome. Changes in pain intensity (BPI severity scale) were the secondary outcome. Higher scores on the BPI scales indicated worse function or pain intensity, and an improvement of 1 point on both scales indicated a clinically significant improvement.
Pain-related function at 1-year follow-up (P =.58) and BPI interference scores (3.4 vs 3.3, respectively; difference, 0.1; 95% CI, -0.5 to 0.7) were comparable in the opioid and nonopioid groups. Over the 1-year study period, participants taking nonopioid analgesics vs opioid medications reported greater improvements in pain intensity (3.5 vs 4.0, respectively; difference, 0.5; 95% CI, 0.0 to 1.0; P =.03).
According to a medication-related symptom checklist, a greater number of medication-related adverse events were found in patients taking opioids vs nonopioid medications (1.8 vs 0.9, respectively; difference, 0.9; 95% CI, 0.3 to 1.5; P =.03).
As the primary outcome was based on patient reports, the authors think that a reporting bias favoring opioids may have been introduced. In addition, the findings from this study may not generalize to patient groups outside of Veterans Affairs clinics.
“Overall, opioids did not demonstrate any advantage over nonopioid medications that could potentially outweigh their greater risk of harms,” concluded the study authors, adding “Poor pain outcomes associated with long-term opioids in observational studies may be attributable to overprescribing and insufficient pain management resources rather than to direct negative effects of opioids.”
Krebs EE, Gravely A, Nugent S, et al. Effect of opioid vs nonopioid medications on pain-related function in patients with chronic back pain or hip or knee osteoarthritis pain: the SPACE randomized clinical trial. JAMA. 2018;319(9):872-882.