Placebo effect in osteoarthritis: Why not use it to our advantage?

Abstract

Osteoarthritis is a major cause of pain and reduced quality of life in the elderly, as well as a major economic burden. Unfortunately, there is no currently effective therapeutic strategy to prevent the progression of Osteoarthritis, and its treatment poses a great challenge to the medical community. Most of the treatment modalities currently available for osteoarthritis have small to moderate effect sizes, according to main metaanalyses and treatment guidelines. On the other hand, literature has demonstrated that placebo is considerably effective. The present article discusses the history of placebo effect and its scientific evidence, comments on ethical issues and provides insights about how it may be used to our advantage when treating osteoarthritic patients. Core tip: Osteoarthritis is a major cause of pain and reduced quality of life in the elderly population, as well as an economic burden. Unfortunately, there is no currently effective treatment, and most of them show small to moderate effect sizes, according to main meta-analyses. On the other hand, literature has demonstrated that placebo has a considerable effect size in osteoarthritis clinical trials. So why not use it to our advantage?de Campos GC. Placebo effect in osteoarthritis: Why not use it to our advantage? World J Orthop 2015; 6(5): 416-420 Available from:

The effect of 12-week garlic supplementation on symptom relief in overweight or obese women with knee osteoarthritis

“…However, positive placebo effect entity has been confirmed in osteoarthritis research, and it seems irrational to disqualify the efficacy of main intervention. 33 A number of strengths and limitations of this study should be recognised. This is, to our knowledge, the first study that has reported on the clinical and practical efficacy of a 12-week garlic supplementation in improving OA pain and other disabling symptoms.…”

“…It is worth noting that the simultaneous decrease in scores in both garlic and placebo groups led to little difference in changes in WOMAC subscales between the 2 groups and, hence, no statistical difference in symptom relief. However, positive placebo effect entity has been confirmed in osteoarthritis research, and it seems irrational to disqualify the efficacy of main intervention …”

Chondroitin sulfate efficacy versus celecoxib on knee osteoarthritis structural changes using magnetic resonance imaging: a 2-year multicentre exploratory study

“…Although patients with knee malalignment were excluded, such angulation was not assessed per se as an outcome variable and may be associated with the knee compartment in which cartilage volume loss could progress despite therapy. Additionally, although there is a well-known placebo effect in OA [50], we did not include a placebo group because it was felt that this would have been unethical, particularly in a 24-month study, and CS has already been shown to have a beneficial effect on JSN and/or pain in a number of placebo-controlled studies in knee OA [13–16, 48]. Similarly, celecoxib has proven pain efficacy over placebo in OA in several studies [51–53].…”

Pulsed Shortwave Therapy in Cervical Osteoarthritis: An NSAID- Controlled, Randomized Clinical Trial

“…A lack of a placebo control is a limitation in this study, but it is now being acknowledge that the placebo effect is built-in to any given treatment [46]. Prior chronic pain placebo controlled trials using this device reported modest placebo effects [29,30] and the device performs better than placebo in acute pain studies [27,28,47] suggesting that the e cacy of the device is not only driven solely by the placebo effect.…”