Systematic review of the effectiveness of glucosamine for knee osteoarthritis

Abstract

Objective: To investigate the effectiveness of glucosamine for knee osteoarthritis (KOA) through the examination of symptomatic and structural effectiveness of the compound, and to increase public awareness, especially in Hong Kong, about its potential benefits contingent upon the quality of the existing research.

Methods, Results: All studies published between 1965 and 2011 in MEDLINE, and from 1980 to 2012 in EMBASE, which evaluated the effectiveness of glucosamine for KOA, were searched and identified using specific keywords. A total of 9 randomized controlled trials out of 672 articles from MEDLINE and 1712 articles from EMBASE were included in this systematic review. The included studies used different outcome measures to compare the effects of glucosamine with other remedies for treating KOA. Similar demographic and clinical characteristics of the subjects between the intervention and the control groups were recorded. The studies were from eight countries. The average age of the subjects in the nine studies were 55 years and they were generally overweight. Though there were discrepancies among the results generated in the included studies, the potential benefits of glucosamine could not be dismissed.

Discussion: Factors about compliance, possible drug-to-drug interaction, unknown placebo, subject characteristics (disease progress and severity, age, gender, and occupation), as well as the dosage of glucosamine could have greatly affected the results of the included studies. Limitations on finding articles about the effectiveness of glucosamine for OA of different sites, the cost-effectiveness of the compound, the assumption of the language restriction, and the risks of biases were raised. More clinical trials with comprehensive considerations of all possible factors affecting the results, are necessary.

Conclusion: Based on this systematic review, the potential effects of glucosamine for KOA remain unclear. More research of different ethnic groups, especially of people in Hong Kong, is needed to raise public awareness about the effectiveness of glucosamine for OA other than the knee globally as well as in Hong Kong.