Long-term effects of glucosamine sulphate on osteoarthritis progression: arandomised, placebo-controlled clinical trial

Background Treatment of osteoarthritis is usually limited to short-term sym ptom control. We assessed the effects of the specific drug glucosamine sulp hate on the long-term progression of osteoarthritis joint structure changes and symptoms. Methods We did a randomised, double-blind placebo controlled trial, in whic h 212 patients with knee osteoarthritis were randomly assigned 1500 mg sulp hate oral glucosamine or placebo once daily for 3 years. Weightbearing, ant eroposterior radiographs of each knee in full extension were taken at enrol ment and after 1 and 3 years. Mean joint-space width of the medial compartm ent of the tibiofemoral joint was assessed by digital image analysis, where as minimum Joint-space width-ie, at the narrowest point-was measured by vis ual inspection with a magnifying lens. Symptoms were scored by the Western Ontario and McMaster Universities (WOMAC) osteoarthritis index. Findings The 106 patients on placebo had a progressive joint-space narrowin g, with a mean joint-space loss after 3 years of -0.31 mm (95% CI -0.48 to -0.13). There was no significant joint-space loss in the 106 patients on gl ucosamine sulphate: -0.06 mm (-0.22 to 0.09). Similar results were reported with minimum joint-space narrowing. As assessed by WOMAC scores, symptoms worsened slightly in patients on placebo compared with the improvement obse rved after treatment with glucosamine sulphate. There were no differences i n safety or reasons for early withdrawal between the treatment and placebo groups. symptoms worsened compared with the Interpretation The long-term combined structure-modifying and symptom-modif ying effects of gluosamine sulphate suggest that it could be a disease modi fying agent in osteoarthritis.