Glucosamine Sulphate Shows Beneficial Effects On Osteoarthritis Progression - Brief Article

Nutrition Research Newsletter, April, 2001

Osteoarthritis, a debilitating muscoloskeletal disorder, is prevalent in older adults. At present the pharmacological treatment usually involves controlling the symptoms of the disease: pain and limitation of function. This is usually accomplished through the use of analgesic agents or nonsteroidal anti-inflammatory drugs (NSAIDs). As of yet, there are no structure-modifying drugs that are able to alter the joint structure favorably, preventing the progression of the disease. Glucosamine sulphate is a constituent of glucosaminoglycans in cartilage matrix and synovial fluid has the potential to promote pharmacological actions in articular cartilage and joint tissues. Multiple short-term studies have demonstrated a significant symptom-improving effect of glucosamine sulphate as well as the safety of the supplement. Based upon these previous works, it is clear that long-term studies are crucial.

A randomized, long-term, placebo-controlled trial was initiated including 212 subjects who were suffering from osteoarthritis. Inclusion criteria were age above 50 years, primary knee osteoarthritis of the medial femorotibial compartment. Exclusion criteria included obesity, a secondary form of osteoarthritis, severe articular inflammation, or medical condition involving a major organ. Subjects were randomized to take 1500 mg of glucosamine sulphate or placebo once daily for three years. They were instructed to take only the following medications for rescue analgesia: Diclofenac, Piroxicam, or Proglumetacin. The patients recorded use of rescue medication in a diary. The primary outcome measure for joint structural changes was represented by the mean joint space width of the medial compartment of the tibiofemoral joint as evidenced in weight bearing, anteroposterior, separate radiographs of each knee at baseline, 1, and 3 years using as standardized technique. Symptoms of osteoarthritis were assessed using a validated, disease-specific questionnaire addressing severity of joint pain, stiffness, and limitation of physical function. Secondary outcomes included use of rescue medications, withdrawal rates, occurrence of adverse events, and routine safety laboratory tests.

The 106 subjects randomized to the placebo group had a progressive joint-space narrowing, with a mean joint-space loss after 3 years of-0.31 mm. The subjects taking the glucosamine sulphate supplement had no significant joint-space loss after the same amount of time. Symptoms worsened slightly in patients taking the placebo while symptoms improved in the glucosamine sulphate group. Researchers found no difference in safety or reasons for early withdrawal between the two groups.

These results are promising. It appears that glucosamine sulphate not only improves symptoms of osteoarthritis but also positively modifies joint structure in those inflicted with the disease.

J. Reginster, R. Deroisy, L. Rovati, et al. Long-term effects of glucosamine sulphate on osteoarthritis progression: a randomized, placebo-controlled clinical trial. The Lancet;357:251-256 (January 27, 2001). [Correspondence: Dr. Jean-Yves Reginster, Bone and Cartilage Metabolism Research Unit (WHO Collaborating Center for Public Aspects of Osteoarticular Disorders), University of Liege, B-4020 Liege Belgium. E-mail: jyreginster@ulg.ac.be].