Publication of NIH study on Glucosamine and Chondroitin Sulfate
The results from the NIH-sponsored glucosamine/chondroitin arthritis intervention trial (GAIT) were published in the New England Journal of Medicine on February 23, 2006
(N Engl J Med. 2006 Feb 23;354(8):795-808; http://content.nejm.org/cgi/content/abstract/354/8/795).
The objective of the study was to rigorously assess the efficacy and safety of chondroitin sulfate and glucosamine HCl alone and in combination in the treatment of patients with painful knee osteoarthritis. The treatment groups included placebo, glucosamine HCl (500 mg three times per day), chondroitin sulfate (400 mg three times per day), the combination of glucosamine and chondroitin sulfate and celecoxib (200mg/day). 1258 patients completed the study. Adverse reactions were mild and similar among the treatment groups. The primary outcome was a 20% improvement in the pain score of the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) from baseline to week 24. Results showed a high placebo effect in 60% of the patients. Neither glucosamine nor chondroitin sulfate alone showed a significantly higher treatment effect as compared to placebo. The response rate in the celecoxib group was significantly higher than in the placebo group. The rate of response to the combination of glucosamine and chondroitin sulfate was significantly higher than in the placebo group for patients with moderate to severe joint pain. The authors identify limitations of the study, including the high placebo response and the relatively mild degree of osteoarthritis knee pain which may have precluded detection of significant treatment effects. While the results on the combination of glucosamine and chondroitin sulfate are encouraging, further studies are needed to conclusively establish efficacy of these agents.
For discussion of this study also see accompanying editorial (Hochberg MC. Nutritional supplements for knee osteoarthritis--still no resolution. N Engl J Med. 2006 Feb 23;354(8):858-60)