We are always impressed with and somewhat curious about the attention research involving glucosamine and similar nutritional supplements receives. Both the studies cited here reached the national media.
A double-blind, randomised controlled trial in 250 patients attending a chronic back pain clinic in Oslo
demonstrated that 1500 mg of glucosamine sulphate was not significantly different from placebo in treating back pain. The subjects were required to be over 25, have experienced low back pain and have had a recent MRI scan demonstrating degenerative change in the lumbar spine. Should we be disappointed by this? We don’t think so. Given that we know that in 85% of patients with back pain a structural pain generator cannot be confidently identified – and it is assumed that the cause is musculoligamentous 1 – and that degenerative change on imaging correlates poorly with experience of symptoms, we wonder why glucosamine might be considered potentially useful treatment for back pain in the first place. 2
Secondly, a meta-analysis of studies comparing glucosamine, chondroitin and placebo in treating the pain of osteoarthritis of the hip and knee
concluded that the supplements had no effect. The study included 10 trials of glucosamine sulphate, glucosamine hydrochloride and chondroitin sulphate. Synovium has previously reported that the evidence supporting glucosamine sulphate is modest and that there is no evidence to support the effectiveness of glucosamine hydrochloride. So would we expect that combining results from studies of both supplements would reveal significant benefits? Clearly there remains insufficient evidence to justify prescribing what are, after all, nutritional supplements – not drugs – for all our patients with osteoarthritis. 3