Effect of glucosamine sulfate on hip osteoarthritis: a randomized trial.

BACKGROUND The effectiveness of glucosamine sulfate as a symptom and disease modifier for osteoarthritis is still under debate. OBJECTIVE To assess whether glucosamine sulfate has an effect on the symptoms and structural progression of hip osteoarthritis during 2 years of treatment. DESIGN Randomized, controlled trial. SETTING Primary care in the Netherlands. PATIENTS 222 patients with hip osteoarthritis who were recruited by their general practitioner. Patients were eligible if they met the American College of Rheumatology clinical criteria for hip osteoarthritis. INTERVENTION 2 years of treatment with 1500 mg of oral glucosamine sulfate or placebo once daily. MEASUREMENTS Primary outcome measures were Western Ontario and McMaster Universities (WOMAC) pain and function subscales over 24 months and joint space narrowing after 24 months. The main secondary outcome measures were WOMAC pain, function, and stiffness after 3, 12, and 24 months. RESULTS At baseline, both groups were similar in demographic and clinical variables. Overall, WOMAC pain did not differ (mean difference [glucosamine sulfate minus placebo], -1.54 [95% CI, -5.43 to 2.36]), nor did WOMAC function (mean difference, -2.01 [CI, -5.38 to 1.36]). Joint space narrowing also did not differ after 24 months (mean difference, -0.029 [CI, -0.122 to 0.064]). Only 1 of the sensitivity analyses, based on extreme assumptions regarding missing assessments due to total hip replacement, provided results consistent with a glucosamine effect. LIMITATIONS Twenty patients had total hip replacement during the trial. Half of the patients had a Kellgren and Lawrence score of 1. CONCLUSION Glucosamine sulfate was no better than placebo in reducing symptoms and progression of hip osteoarthritis. International Standard Randomised Controlled Trial Number: ISRCTN54513166.