Meta-analysis: chondroitin for osteoarthritis of the knee or hip.
BACKGROUND
Previous meta-analyses described moderate to large benefits of chondroitin in patients with osteoarthritis. However, recent large-scale trials did not find evidence of an effect.


OBJECTIVE
To determine the effects of chondroitin on pain in patients with osteoarthritis.


METHODS
The authors searched the Cochrane Central Register of Controlled Trials (1970 to 2006), MEDLINE (1966 to 2006), EMBASE (1980 to 2006), CINAHL (1970 to 2006), and conference proceedings; checked reference lists; and contacted authors. The last update of searches was performed on 30 November 2006.


METHODS
Studies were included if they were randomized or quasi-randomized, controlled trials that compared chondroitin with placebo or with no treatment in patients with osteoarthritis of the knee or hip. There were no language restrictions.


METHODS
The authors extracted data in duplicate. Effect sizes were calculated from the differences in means of pain-related outcomes between treatment and control groups at the end of the trial, divided by the pooled SD. Trials were combined by using random-effects meta-analysis.


RESULTS
20 trials (3846 patients) contributed to the meta-analysis, which revealed a high degree of heterogeneity among the trials (I2 = 92%). Small trials, trials with unclear concealment of allocation, and trials that were not analyzed according to the intention-to-treat principle showed larger effects in favor of chondroitin than did the remaining trials. When the authors restricted the analysis to the 3 trials with large sample sizes and an intention-to-treat analysis, 40% of patients were included. This resulted in an effect size of -0.03 (95% CI, -0.13 to 0.07; I2 = 0%) and corresponded to a difference of 0.6 mm on a 10-cm visual analogue scale. A meta-analysis of 12 trials showed a pooled relative risk of 0.99 (CI, 0.76 to 1.31) for any adverse event.


CONCLUSIONS
For 9 trials, the authors had to use approximations to calculate effect sizes. Trial quality was generally low, heterogeneity among the trials made initial interpretation of results difficult, and exploring sources of heterogeneity in meta-regression and stratified analyses may be unreliable.


CONCLUSIONS
Large-scale, methodologically sound trials indicate that the symptomatic benefit of chondroitin is minimal or nonexistent. Use of chondroitin in routine clinical practice should therefore be discouraged.
Reichenbach
Stephan
S
University of Bern, Bern, Switzerland.
Sterchi
Rebekka
R
Scherer
Martin
M
Trelle
Sven
S
Bürgi
Elizabeth
E
Bürgi
Ulrich
U
Dieppe
Paul A
PA
Jüni
Peter
P
D000368:Aged; D002809:Chondroitin Sulfates / Q000009:adverse effects / Q000627:therapeutic use*; D005260:Female; D006621:Hip Joint / Q000000981:diagnostic imaging; D006801:Humans; D007719:Knee Joint / Q000000981:diagnostic imaging; D008297:Male; D008875:Middle Aged; D015207:Osteoarthritis, Hip / Q000000981:diagnostic imaging / Q000188:drug therapy* / Q000503:physiopathology; D020370:Osteoarthritis, Knee / Q000000981:diagnostic imaging / Q000188:drug therapy* / Q000503:physiopathology; D010146:Pain / Q000188:drug therapy* / Q000209:etiology; D011859:Radiography; D016032:Randomized Controlled Trials as Topic / Q000592:standards
D002809:Chondroitin Sulfates