Glucosamine Not Linked to Arthritis Relief

Summary
Long-term treatment of osteoarthritis with painkillers and non-steroidal anti-inflammatory medications such as ibuprofen can lead to adverse effects of the digestive and cardiovascular system. This study was done to assess the effectiveness of both glucosamine and chondroitin, which are widely prescribed for this condition by doctors for improving joint pain and progression of osteoarthritis. It was found that neither of these drugs had a beneficial effect on the improvement of pain or progression of disease in osteoarthritis. The authors question and discourage the prescription of these medications in newly diagnosed patients.

Introduction
Glucosamine and chondroitin are cartilage constituents and their use is being recommended in several guidelines for osteoarthritis. Global sales of glucosamine supplements have increased by 60 percent compared to the figures in the 2003. And the forecasted sales could reach around $2.3 billion by the year 2013. Results from previous studies regarding the use of chondroitin and glucosamine as treatment modalities in osteoarthritis are conflicting. While studies that supported their use had either a small study group or a poor quality, studies that were reliable found no effect on their use in osteoarthritis. Therefore, this study was done to overcome the problems in the past studies. Various reliable previous studies were consolidated in this study and elaborate statistical analysis was done to validate the true effect of the use of these substances.

Methodology

  • Relevant previous studies on the treatment of osteoarthritis that compared the use of “chondroitin sulphate, glucosamine sulphate, glucosamine hydrochloride, or a combination of any two with placebo” or with each other were included for analysis. All chosen studies had at least a study group and a control group of around 100 patients each.
  • The intensity of pain and the width of joint space (determined on X-ray films) were the parameters used for analyzing the outcome of these drugs.
  • Two reviewers each evaluated the various studies for eligibility and again, two evaluated the included studies for their quality.
  • Data collection from all the previous studies and precise statistical analysis was done to obtain the results.

Key findings

  • Out of 58 potentially eligible reports, 12 reports describing 10 studies covering 3,803 patients in total were found to be of adequate quality and fulfilled the inclusion criteria and hence were included in the analysis.
  • On statistical analysis from all the previous studies, there was only a minimal difference of -0.4 cm for glucosamine, -0.3 cm for chondroitin, and -0.5 cm for the combination of glucosamine and chondroitin (on a 10 cm visual scale to evaluate pain), with respect to placebo. This showed no clinical relevance of the drugs to joint pain.
  • The differences in joint space were negligible, even after medications and clinically irrelevant.
  • It was also observed that studies sponsored by independent sources showed smaller effects than studies sponsored by the pharmaceutical industry.

Shortcomings
The authors comment that there could have been a few clinical inconsistencies in the previous studies and there were no possibilities of assessing them. The patients had great variation in the extent of disease and few had near total or total cartilage damage. The improvement in joint spaces of these patients could have been affected by the experimental preparations and measurement by different instruments, which is a source of bias.

Conclusion
This study indicates that glucosamine and chondroitin or even both drugs in combination neither decrease joint pain nor affect the joint space narrowing when compared with those patients who were treated with placebo. The authors, however, affirm that neither of these drugs is dangerous. Over the past few years, these have become commonly prescribed drugs for osteoarthritis, with a total market estimate of nearly $2 billion in sales.  The authors conclude,  “we see no harm in having patients continue these preparations as long as they perceive a benefit and cover the costs of treatment themselves.” Based on their comprehensive study, they also recommend a cessation in prescription of these drugs to patients with no other prior treatment modalities.

For More Information:

Effect of Glucosamine and Chondroitin on Osteoarthritis

Publication Journal: The British Medical Journal, 2010

By Simon Wandel, Peter Juni; Institute of Social and Preventive Medicine, University of Bern, Switzerland

*FYI Living Lab Reports Are Summaries of the Original Research.
Tags from the story
, , ,