Randomized, controlled trial of glucosamine for treating osteoarthritis of the knee

Objective To determine the effectiveness of glucosamine in reducing pain from osteoarthritis of the knee. Design Randomized, double-blind parallel trial of glucosamine 500 mg three times daily or a placebo for 2 months. Setting Veterans Affairs Medical Center, Prescott, AZ. Participants Ninety-eight patients aged 34 to 81 being treated for osteoarthritis of the knee. Main outcome measures Pain intensity both at rest and while walking as assessed by a visual analog scale at baseline and after 30 and 60 days of treatment. Results Forty-nine patients were randomly allocated ro each group. There was no statistical difference between the two groups in scores on the visual analog scale at 30 days for resting (mean [SD] score placebo group 3.5 [2.7] vs 3.3 [2.4] glucosamine group, P=0.66) or walking (5.1 [2.6] vs 5.3 [2.4], P=0.69); there was also no difference at 60 days for resting (3.4 [2.5] vs 3.2 [2.5], P=0.81) or walking (4.9 [2.2] vs 4.9 [2.8], P=0.90). There was also no statistical difference between groups in the mean change from baseline in scores on the visual analog scale (mean [SD] change for walking at 60 days placebo group -1.5 [2.5] vs glucosamine group -1.4 [3.0], P=0.77). Two participants caking glucosamine and 4 taking placebo wihdrew from the study due to adverse side effects (P=0.67). Conclusion Glucosamine was no better than placebo in reducing pain from osteoarthritis of the knee in this group of patients.