Chondroitin Meta-Analysis Misses Mark
BERN, Switzerland - A meta-analysis published in the April issue of the Annals of Internal Medicine (146, 8:580-90, 2007) concluded chondroitin supplementation has minimal to no effect on osteoarthritis (OA); but, nutrition industry insiders point to many flaws in the review design, including undefined OA endpoints and a severely limited number of trials used to reach its conclusion.
The meta-analysis 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, narrowing the list of randomized or quasi-randomized controlled trials on chondroitin and OA pain to 20 trials, involving a total of 3,846 patients. The smaller trials not employing an intent-to-treat protocol showed greater benefits from chondroitin than did the other trials reviewed. When the researchers narrowed the review to three large-scale trials—representing only 40 percent of the patients—they found symptomatic benefit of chondroitin was minimal or nonexistent, and concluded the use of chondroitin in routine clinical practice should be discouraged.

Among other objections to this meta-analysis, the Council for Responsible Nutrition (CRN) took issue with the reviewers basing their decision on three trials, excluding 17 other trials selected and ignoring the approximately 300 scientific reports on chondroitin available. “Meta-analysis can be a valid tool for scientific evaluation, but also has recognized limitations,” said Andrew Shao, Ph.D., vice president, scientific and regulatory affairs for CRN. “One can include and exclude studies in various combinations, but the bottom line is consumers use glucosamine and chondroitin supplements because they work.”

CRN reiterated that chondroitin is a safe, affordable and beneficial option for helping maintain mobility and reduce discomfort associated with osteoarthritis, particularly when combined with glucosamine. “With over 21 million osteoarthritis sufferers in the United States alone, a conclusion based on only three studies hardly seems representative of the population in question,” the group responded.

A similar statement was released by the Natural Products Association (NPA), which noted the reviewers made no distinction between mild, moderate and severe OA, which all involve very different treatment regimens. In contrast, they noted the 2006 National Institutes of Health (NIH) Glucosamine/chondroitin Arthritis Intervention Trial (GAIT) showed positive benefits of chondroitin by itself for mild osteoarthritis, and statistically significant benefit in combination with glucosamine for patients with severe osteoarthritis.

“Bottom line: Chondroitin, especially when combined with glucosamine, is safe and effective, and compared to the other options for arthritis pain, it’s one of the few options without dangerous side effects,” said Daniel Fabricant, Ph.D., vice president of scientific and regulatory affairs for NPA. “It’s important to keep in mind that most consumers use a combination of glucosamine and chondroitin, not just chondroitin by itself.”

SOURCE: Natural Products Insider




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