SAN ANTONIO, Texas – While millions of patients around the world with osteoarthritis (OA) take glucosamine sulfate tablets to ease pain and improve function, a newly released study documents the disease-modifying clinical endpoints that support the efficacy of this well-known over-the-counter medication.

The findings emerged from an analysis of 259 patients (133 in a glucosamine sulfate group; 126 on placebo) that assessed "responders" or "failures" to therapy, employing recognized secondary endpoints for structure-modifying drugs in OA.

In the glucosamine sulfate group, 71 patients (53%) were considered to be responders, showing less than 0.5 mm joint space narrowing (JSN) and at least a 20% improvement in WOMAC (Western Ontario and McMaster Universities Osteoarthritis Index) total or WOMAC pain scores, compared to 41 patients (32%) in the placebo group (P = 0.0007), according to a report presented by researchers at the World Health Organization Center for Public Health Aspects of Osteoarticular Diseases in Liege, Belgium.

In addition, when factoring in WOMAC pain and function scores and JSN, there were 67 patients (50%) who were characterized as responders in the glucosamine group and 48 (38%) in the control group, according to the WHO report.

The lead author, Olivier Bruyere, PhD, defined a "failure" as an individual who either had reached a significant threshold of joint space narrowing or lacked a clinically relevant improvement in symptoms.

"I think glucosamine really works," Dr. Bruyere said at a late-breaking poster presentation October 19 during the 2004 annual meeting of the American College of Rheumatology.

"There have been a number of studies that indicate glucosamine has a beneficial effect in patients with arthritis," said Alan Roumm, MD, a rheumatologist in Harrisburg, Pennsylvania, who is on the clinical faculty at the Hershey Medical Center in Pennsylvania. "There are probably 25 million people in the United States who use glucosamine," he said, including a number of his own patients. "I think the supplement is inexpensive and safe and appears to have some impact on the disease, so it doesn't bother me if my patients use it."

Dr. Roumm added that some of the difficulty in assessing benefit using joint space narrowing as the main criteria is a lack of standardization of the terms and measurements of that space.

Reference:

Bruyere O, Pavelka K, Richy F, Giacovelli G, Rovati LC, Reginster J-Y. Responders to glucosamine sulfate in knee osteoarthritis. Presented at: Annual Meeting of the American College of Rheumatology; October 19, 2004; San Antonio, Tex. Abstract L7.