Buenos Aires, Argentina, May 14th, 2007 -- INTER FARMA´s response to the “Meta-analysis: Chondroitin for Osteoarthritis of the Knee or Hip” written by Stephan Reichenbach, MD; Rebekka Sterchi, MD; Martin Scherer, MD; Sven Trelle, MD; Elizabeth Bürgi, PhD; Ulrich Bürgi, MD; Paul A. Dieppe, MD; and Peter Jüni, MD, published on April 17 in the Annals of Internal Medicine, Volume 146, Issue 8, Pages 580 to 590.
While a meta-analysis can be a valid tool for a scientific assessment, it does have some limitations: the authors may decide whether to include or exclude studies with significant conclusions for the purpose they intend to evidence. In this meta-analysis, “Chondroitin for Osteoarthritis of the Knee or Hip”, more than three hundred studies dealing with the use of Chondroitin Sulfate in arthritis or osteoarthritis could have been included; however, the researchers only reviewed 20 clinical trials at random of which 17 were then excluded. Thus, the authors restricted their analysis to only three studies that they subjectively selected for their highest quality, and most of the scientific production carried out during the last 30 years was excluded with the apparent purpose of concluding that Chondroitin Sulfate only acts as placebo.
There is a population of more than 20 million people in the USA suffering from osteoarthritis, and the number is even higher if we include patients suffering from early arthritis, where the signs and symptoms of osteoarthritis are not yet clear. This universe is huge and, therefore, a conclusion based on a sample including only three studies hardly seems representative of a population suffering from osteoarthritis or arthritis.
The purpose of the meta-analysis, “Chondroitin for Osteoarthritis of the Knee or Hip”, was to assess the effects of Chondroitin Sulfate in the pain experienced by patients with osteoarthritis. This analysis concludes that the effect of Chondroitin Sulfate is minimal or non-existent; the use of Chondroitin should therefore be discouraged. From the most elementary scientific perspective, it is amazing that the authors carried out this “study” to assess pain. It is clear and well-known that Chondroitin Sulfate is not an analgesic, but a mucopolysaccharide which action is to provide a repairing effect, decreasing inflammatory response. Even though Chondroitin Sulfate secondarily helps alleviate the pain, it improves joint function as has been seen and evidenced in different experimental models during the last three decades.
At the same time, in the GAIT trial, mentioned by the authors as a large-scale assessment, the patients of the group receiving Chondroitin Sulfate showed a statically significant recovery of joint function, evidencing that this effect was related to the inflammatory response. Also in this trial, the subgroup of patients with moderate to severe pain experienced significant relief when Chondroitin Sulfate was administered in combination with Glucosamine, while the positive control with Celecoxib did not evidence superiority over placebo in this subgroup of patients.
In the other two large-scale trials mentioned by the authors, one of the results studied explains how the joint space became narrow during the osteoarthritis process. In these two trials, it was evidenced that the patients receiving Chondroitin Sulfate better preserved joint space, while the opposite was observed in the group receiving placebo.
In the different clinical trials on which this meta-analysis was based, the conclusion is that Chondroitin Sulfate may improve joint function and, secondarily, alleviate the pain as it has a specific function in the inflammatory response. An indirect evidence of the clinical effectiveness of Chondroitin Sulfate is the reduction in the consumption of analgesic and anti-inflammatory drugs in daily clinical practice. It is clear that this represents a significant advantage for patients, not only from an economic perspective but particularly regarding biosafety. This is highly beneficial for elderly patients.
In addition, we should not forget that osteoarthritis is a chronic pathology affecting particularly older people concomitantly suffering from hypertension and diabetes. In these cases, the use of analgesic and anti-inflammatory drugs needs to be strictly monitored to avoid adverse effects and drug-drug interactions. As regards all clinical trials included in the meta-analysis and pharmacological research carried out in Europe and Latin America, no serious adverse event or drug-drug interactions have been reported regarding the use of Chondroitin Sulfate in combination with other drugs, what is very important for the clinical framework.
Dr. Jose N. Racca MD, MSc, PhD
Professor at UBA (Universidad de Buenos Aires) and UAJFK (Universidad Argentina John F. Kennedy)
Specialist in Internal Medicine and Gastroenterology
Director of the Nutrition School, UAJFK (Universidad Argentina John F. Kennedy)
Consultant on Clinical Pharmacology and Nutrition for INTER FARMA