By Nigel Praities
Commonly-used supplements used to treat osteoarthritis are no better than placebo and should not be prescribed by GPs, concludes an analysis of trials.
The meta analysis included ten trials involving nearly 4,000 patients and compared the effectiveness of glucosamine, chondroitin and the combination of both with placebo.
The researchers found no significant differences in pain scores or the narrowing of joint space for either supplement separately, or in combination, compared with placebo.
The overall difference in pain intensity with placebo was -0.4 cm – on a 10cm visual analogue scale – compared with -0.4 cm for glucosamine, -0.3 cm for chondroitin and -0.5 for a combination of the two supplements.
The authors say that although data from the manufacturer-independent Long Term Evaluation of Glucosamine Sulphate Study – involving 600 patients – will be interesting when available next year, they believe it is ‘unlikely any future trials will show a clinical relevant benefit’.
Study leader Dr Simon Wandel, research fellow at the Institute of Social and Preventative Medicine at the University of Bern, Switzerland, said: ‘Health authorities and health insurers should not cover the costs of these preparations, and new prescriptions to patients who have not received treatment should be discouraged.’
BMJ; online 17 September
Glucosamine is commonly used in osteoarthritis