Osteoarthritis is the most prevalent chronic articular disease, in which pain is one of the main symptoms and a major determinant of functional loss. Several therapeutic options have been proposed, including glucosamine, but its actual usefulness has not yet been established. To answer this question, we searched in Epistemonikos database, which is maintained by screening multiple databases. We identified 11 systematic reviews including 35 randomized trials answering the question of interest. We extracted data, conducted a meta-analysis and generated a summary of findings table using the GRADE approach. We concluded it is not clear whether glucosamine decreases pain or improves functionality in osteoarthritis because the certainty of the evidence is very low.
OBJECTIVES: Systematic review of outcomes of three treatments for osteoarthritis (OA) of the knee: intra-articular viscosupplementation; oral glucosamine, chondroitin or the combination; and arthroscopic lavage or debridement.
DATA SOURCES: We abstracted data from: 42 randomized, controlled trials (RCTs) of viscosupplementation, all but one synthesized among six meta-analyses; 21 RCTs of glucosamine/chondroitin, 16 synthesized among 6 meta-analyses; and 23 articles on arthroscopy. The search included foreign-language studies and relevant conference proceedings.
REVIEW METHODS: The review methods were defined prospectively in a written protocol. We sought systematic reviews, meta-analyses, and RCTs published in full or in abstract. Where randomized trials were few, we sought other study designs. We independently assessed the quality of all primary studies.
RESULTS: Viscosupplementation trials generally report positive effects on pain and function scores compared to placebo, but the evidence on clinical benefit is uncertain, due to variable trial quality, potential publication bias, and unclear clinical significance of the changes reported. The Glucosamine/Chondroitin Arthritis Intervention Trial (GAIT), a large (n=1,583), high-quality, National Institutes of Health-funded, multicenter RCT showed no significant difference compared to placebo. Glucosamine sulfate has been reported to be more effective than glucosamine hydrochloride, which was used in GAIT, but the evidence is not sufficient to draw conclusions. Clinical studies of glucosamine effect on glucose metabolism are short term, or if longer (e.g., 3 years), excluded patients with metabolic disorders. The best available evidence for arthroscopy, a single sham-controlled RCT (n=180), showed that arthroscopic lavage with or without debridement was equivalent to placebo. The main limitations of this trial are the use of a single surgeon and enrollment of patients at a single Veterans Affairs Medical Center. No studies reported separately on patients with secondary OA of the knee. The only comparative study was an underpowered, poor-quality trial comparing viscosupplementation to arthroscopy with debridement.
CONCLUSIONS: Osteoarthritis of the knee is a common condition. The three interventions reviewed in this report are widely used in the treatment of OA of the knee, yet the best available evidence does not clearly demonstrate clinical benefit. Uncertainty regarding clinical benefit can be resolved only by rigorous, multicenter RCTs. In addition, given the public health impact of OA of the knee, research on new approaches to prevention and treatment should be given high priority.
Osteoarthritis is the most prevalent chronic articular disease, in which pain is one of the main symptoms and a major determinant of functional loss. Several therapeutic options have been proposed, including glucosamine, but its actual usefulness has not yet been established. To answer this question, we searched in Epistemonikos database, which is maintained by screening multiple databases. We identified 11 systematic reviews including 35 randomized trials answering the question of interest. We extracted data, conducted a meta-analysis and generated a summary of findings table using the GRADE approach. We concluded it is not clear whether glucosamine decreases pain or improves functionality in osteoarthritis because the certainty of the evidence is very low.
