Conclusion. Placebo treatment and CBT are inferior to NSAIDs in managing pain for patients with knee osteoarthritis. The difference in pain may not be clinically important, and there were no differences in function at 14 weeks.
Commentary
Osteoarthritis is a common chronic condition that causes pain and disability and is often treated with oral analgesics. NSAIDs, despite few high-quality trials demonstrating their efficacy, are among the most commonly used treatment for osteoarthritis pain.1 NSAID therapy, however, does have potential side effects, such as gastric reflux and renal dysfunction.2 This withdrawal trial with placebo control contributes further evidence of the effectiveness of NSAIDs on knee osteoarthritis, demonstrating that indeed NSAIDs improve pain scores to a greater degree than placebo treatment. Augmenting placebo treatment with nonpharmacologic CBT was inferior to NSAIDs in pain management. The authors pointed out that the difference in pain score may not be clinically important, and that lower-extremity function was not different between the groups, concluding that, despite the higher pain score, CBT could be a treatment option, particularly for those who may have difficulty tolerating NSAID treatment.
The study population had a number of chronic conditions in addition to having knee arthritis, and thus likely were taking multiple medications for chronic disease management. Use of multiple medications is associated with an increased risk of rug interactions and adverse effects of medications.3 Thus, this attempt to assess whether a nonpharmacologic alternative treatment is noninferior to a drug treatment is a step toward building the evidence base for deprescribing and enhancing medication safety.4 Previous studies have examined other nonpharmacologic treatments for knee arthritis, such as acupuncture,5 and it is worthwhile to consider combining nonpharmacological approaches as an alternative to oral analgesic medication use.
Applications for Clinical Practice
This study advances our understanding of the effect of NSAID use on knee osteoarthritis when compared to placebo with CBT. Although this is a negative study that failed to show that placebo combined with CBT is noninferior to NSAIDs, it did quantify the expected treatment effect of NSAIDs and showed that this effect likely is not clinically important and/or does not alter lower-extremity function. Further studies are needed to identify other nonpharmacologic approaches and test whether combinations of approaches are effective in the management of chronic pain from osteoarthritis.
–William W. Hung, MD, MPH