Subgroup analyses of the effectiveness of oral glucosamine for knee and hip osteoarthritis
To evaluate the effectiveness of oral glucosamine in subgroups of people with hip or knee osteoarthritis (OA) based on baseline pain severity, body mass index (BMI), sex, structural abnormalities and presence of inflammation using individual patient data. Methods: After a systematic search of the literature and clinical trial registries, all randomised controlled trials (RCTs) evaluating the effect of any oral glucosamine substance in patients with clinically or radiographically defined hip or knee OA were contacted. As a minimum, pain, age, sex and BMI at baseline and pain as an outcome measure needed to be assessed.
Of 21 eligible studies, six (n=1663) shared their trial data with the OA Trial Bank. Five trials (all independent of industry, n=1625) compared glucosamine with placebo, representing 55% of the total number of participants in all published placebo controlled RCTs. Glucosamine was no better than placebo for pain or function at short (3 months) and long-term (24 months) follow-up. Glucosamine was also no better than placebo among the predefined subgroups. Stratification for knee OA and type of glucosamine did not alter these results.
Although proposed and debated for several years, open trial data are not widely made available for studies of glucosamine for OA, especially those sponsored by industry. Currently, there is no good evidence to support the use of glucosamine for hip or knee OA and an absence of evidence to support specific consideration of glucosamine for any clinically relevant OA subgroup according to baseline pain severity, BMI, sex, structural abnormalities or presence of inflammation.
Rianne M Rozendaal 1
Marienke van Middelkoop 1
Hans J W Bijlsma 2
Michael Doherty 3
Krysia S Dziedzic 4
L Stefan Lohmander 5
Timothy McAlindon 6
Weiya Zhang 7
Sita Bierma Zeinstra 1
1 Erasmus MC Medical University Center Rotterdam, Department of General Practice, The Netherlands, 2. University Medical Center Utrecht, Department of Rheumatology & Clinical Immunology, Utrecht, 3. Division of Rheumatology, Orthopaedics and Dermatology, University of Nottingham, Nottingham, 4. Research User Group, Arthritis Research UK Primary Care Centre, Research Institute of Primary Care and Health Sciences, Keele University, Keele, United Kingdom, 5. Lund University, Department of Orthopaedics, Clinical Sciences Lund, Sweden, 6. Tufts University, Department of Medicine, Boston, 7. Division of Rheumatology, Orthopaedics and Dermatology, University of Nottingham, Nottingham