Study doubts benefit of chondroitin for arthritis

By Julie Steenhuysen

CHICAGO (Reuters) - Though many swear by it, the dietary supplement chondroitin is no better than a placebo at easing the hip and knee pain of arthritis and its use should be discouraged, European researchers said on Monday.

Chondroitin sulfate, one of the building blocks of cartilage, is widely sold in the United States in combination with glucosamine as a treatment for the aches and pains of osteoarthritis. The supplement has annual U.S. sales of about $1 billion a year.

In Europe, the supplement is typically sold by itself for arthritis relief and in Switzerland is featured on a list of insurance-approved treatments.

Despite its popularity, studies have differed over whether chondroitin relieves arthritis pain.

Researchers at the University of Berne, Switzerland, did a wide-reaching analysis of published research and found that in the biggest and most carefully conducted studies, chondroitin probably has no effect at relieving osteoarthritis, a painful degeneration of the cartilage in the knee and hip joints.

"Currently, we do not have any evidence to suggest that chondroitin helps decrease pain more than placebo," said Peter Juni, an epidemiologist whose study appears in this week's Annals of Internal Medicine.

"The good news is we do not have evidence to suggest that chondroitin is unsafe," he said in a telephone interview.

The researchers said the product did not work, and thus, should not be recommended as part of a daily treatment regimen.

Juni said smaller, earlier trials have suggested the product was very effective, but larger, more recent studies have challenged that idea.

"High-quality studies don't show any effect," he said.

RESULTS CHALLENGED

The Natural Products Association, which reviewed the analysis, faulted the study because it only looked at chondroitin and it made no distinction between mild, moderate and severe arthritis.

The group cited a large study sponsored by the U.S. National Institutes of Health that it said showed a statistically significant benefit when chondroitin was used in combination with glucosamine in 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," Daniel Fabricant, vice president of scientific and regulatory affairs for the association, said in a statement.

In the 2006 NIH study cited by the group, the overall finding was that glucosamine, chondroitin and a combination of the two did not work significantly better than placebo.