Patients' welfare should be primary concern

EDITOR—Chard and Dieppe discussed the use of glucosamine in treating osteoarthritis.1 Osteoarthritis is traditionally treated with non-steroidal anti-inflammatory drugs and analgesics, just masking symptoms but doing nothing to improve the disease. Worst of all, non-steroidal anti-inflammatory drugs alone cause over 16 500 deaths and over 103 000 admissions to hospital each year in the United States.2

With regard to evidence based medicine, the authors of the Cochrane review on non-steroidal anti-inflammatory drugs for osteoarthritis of the knee conclude that, despite the large number of publications in this area, there are few randomised controlled trials.3 Furthermore, most trials comparing two or more such drugs have substantial design errors. The reviewers conclude that no substantial evidence is available related to efficacy, to distinguish between equivalent recommended doses of non-steroidal anti-inflammatory drugs. Had studies used appropriate doses of the drug that was being compared, most would have been sufficiently powerful to detect clinically important differences in efficacy. As differences in efficacy between non-steroidal anti-inflammatory drugs have not been recorded, the prescription of such a drug for osteoarthritis of the knee should be based on relative safety, acceptability to the patient, and cost.

A Cochrane review on glucosamine gave the following main results.4 Collectively, the reviewers identified 16 randomised controlled trials that provided evidence that glucosamine is both effective and safe in patients with osteoarthritis. In the 13 randomised controlled trials in which glucosamine was compared with …