Study: Glucosamine Appears to Slow Progression of Knee Osteoarthritis

The supplement glucosamine appears to slow the progression of knee osteoarthritis, according to a report in the July 14 issue of the Archives of Internal Medicine.

Lead researcher Florent Richy of the University of Liège in Belgium and his colleagues, examined the effectiveness of glucosamine sulfate and chondroitin sulfate -- two over-the-counter supplements that have attracted a wide following -- by analyzing data from 15 randomized clinical trials.

Specifically, the researchers looked at the effectiveness of the compounds in regard to their effects on joint space narrowing, pain, stiffness, knee function, mobility, safety and patient response.

They found glucosamine sulfate to be effective in regard to all outcomes, while chondroitin was found to be effective on pain, walking ability, mobility and knee function and patient response. Safety and tolerance was shown to be excellent for both compounds.

Richy told Medical Week that the reassessment of the central role of non-steroidal anti-inflammatory drugs in treating osteoarthritis has favored development of drugs that interfere directly with the disease process, aiming at the protection and regeneration of cartilage.

"Chondroitin 4 and 6 and glucosamine sulfates, two natural compounds found in the healthy cartilage, have been investigated for 20 years, and their exact slot in the therapeutic strategy of osteoarthritis remains debated," Richy said.

Noting that the study was aimed at clarifying the situation regarding to the usefulness of the compounds in patients with knee osteoarthritis, Richy said his goal and that of his colleagues was to "provide a document doctors and scientists could use."

Besides finding that glucosamine sulfate and chondroitin sulfate were equally as effective in relieving the symptoms of osteoarthritis at a minimal time of two weeks, Richy and his team also demonstrated that glucosamine sulfate was effective structurally as illustrated by the significant reduction of joint space narrowing.

"Nevertheless, further long-term studies are needed to confirm and evaluate the structural efficacy of chondroitin sulfate," said Richy.

Since the study demonstrated a structure-modifying effect for glucosamine sulfate, Richy said further studies on the relationship between structural and symptomatic changes and on possible use in prevention "are required to determine the role of this compound as a disease-modifying agent in osteoarthritis."

Other sources: Archives of Internal Medicine 2003;163:1514-1522