Newswise — Glucosamine may not help to prevent joint damage in osteoarthritis of the knee, according to research presented this week at the American College of Rheumatology Annual Scientific Meeting in Philadelphia, Pa.

Osteoarthritis, or OA as it is commonly called, is the most common joint disease affecting middle-aged and older people. It is characterized by progressive damage to the joint cartilage—the slippery material at the end of long bones—and causes changes in the structures around the joint. These changes can include fluid accumulation, bony overgrowth, and loosening and weakness of muscles and tendons, all of which may limit movement and cause pain and swelling.

Most commonly affected are the weight-bearing joints—the knees, hips and spine. Osteoarthritis in the knee and hip areas can generate chronic pain or discomfort during standing or walking.

Prior studies of glucosamine and its role in the prevention of joint damage in knee OA, as assessed by X-ray, have produced conflicting results. Researchers recently set out to determine the short-term effectiveness of glucosamine in preventing of the worsening of cartilage damage in knee OA in a 24-week study.

The study included 201 participants—49 percent were women—with a mean age of 52 years old—who had mild to moderate knee pain. Participants were randomly placed into two groups with 98 participants receiving glucosamine and 103 receiving placebo.

Each participant had an MRI and knee X-rays performed on both knees at the beginning of the study and again at 24 weeks into the study. Researchers factored in things like age, sex, body mass index and joint space narrowing to determine the odds of developing cartilage damage, bone marrow lesions and synovitis in both groups.

Researchers found that the odds of worsening cartilage damage in the glucosamine group were the same as for those patients in the placebo group. The odds of worsening bone lesions were also found to be the same for both groups. In addition, when using a urine biomarker as a basis for comparison, no difference in cartilage synthesis was found between the two groups,

“In this six-month study using state-of-the-art MR imaging we were not able to demonstrate any benefit of glucosamine on the prevention of worsening joint damage in individuals with mild to moderate knee pain,” explains C. Kent Kwoh, MD; professor of medicine and epidemiology, division of rheumatology and clinical immunology, University of Pittsburgh School of Medicine, Pittsburgh, Pa., and lead investigator in the study.

The ACR is an organization of and for physicians, health professionals, and scientists that advances rheumatology through programs of education, research, advocacy and practice support that foster excellence in the care of people with or at risk for arthritis and rheumatic and musculoskeletal diseases. For more information on the ACR’s annual meeting, see www.rheumatology.org/annual.

Editor’s Notes: Dr. Kwoh will present this research during the ACR Annual Scientific Meeting at the Pennsylvania Convention Center at 5:00 PM on Tuesday, October 20 in Room 108 B. Dr. Kwoh will be available for media questions and briefing at 1:30 PM on Monday, October 19 in the on-site press conference room, 109 A. Presentation Number: 1942

The Joints On Glucosamine (JOG) Study: A Randomized, Double-Blind, Placebo-Controlled Trial to Assess the Structural Benefit of Glucosamine in Knee Osteoarthritis Based On 3T MRI

C. Kent Kwoh, MD , Rheum & Clinical Immunology, University of Pittsburgh, VA Pittsburgh Healthcare System, Pittsburgh, PA Frank W. Roemer, M.D., Department of Radiology, Boston University School of Medicine, Boston, MA Michael J. Hannon, MA, University of Pittsburgh, Pittsburgh, PA Carolyn E. Moore, Texas Woman's University, Houston, TX John M. Jakicic, University of Pittsburgh, Pittsburgh, PA Ali Guermazi, M.D. , Department of Radiology, Boston University School of Medicine, Boston, MA Stephanie M. Green, University of Pittsburgh, Pittsburgh, PA Robert M. Boudreau, PhD, Epidemiology, University of Pittsburgh, Pittsburgh, PA

Purpose: Prior studies of the structural benefit of glucosamine in knee osteoarthritis (KOA) as assessed by radiographs have yielded conflicting results. The aim of this study was to determine the short-term efficacy of glucosamine based on decreased worsening of structural lesions in KOA as assessed using 3T MRI.

Method: The Joints on Glucosamine (JOG) study was a 24-week double-blind placebo controlled trial of 1500 mg glucosamine hydrochloride once daily in beverage form compared to placebo. The primary outcome was decreased development of cartilage damage. Eligible participants had mild to moderate knee pain (WOMAC score > = 125). 3T MRI of both knees was performed at baseline and at 24 weeks on a Siemens Trio using the same pulse sequences used in the Osteoarthritis Initiative (OAI): sagittal fat-suppressed (FS) 2D TSE intermediate-weighted (IW); sagittal 3D dual-echo steady state (DESS) WE; and axial and coronal reformations of sagittal 3D DESS WE. Cartilage damage, bone marrow lesions (BMLs) and synovitis in each knee were scored according to the WORMS system. Baseline fixed-flexion knee x-rays were read for Kellgren-Lawrence (K-L) grade and radiographic features such as joint space narrowing using the OARSI grading system. All MRIs and x-rays were read masked to treatment assignment but not to baseline vs. follow-up order. Urinary excretion of C-terminal cross linking telopeptide of type II collagen (uCTX-II) as a biomarker of cartilage synthesis was also assessed. An Intent-to-Treat analysis with last event carried forward was performed. Negative binomial regression for cartilage defects and multivariate logistic regression for worsening BML, taking into account clustering of knees within an individual and adjusted for gender, age, BMI, baseline WOMAC, and K-L grade, were performed to determine the odds (aOR) of worsening based on treatment group assignment. These covariates were used in a linear regression model for uCTX-II.

Results: There were a total of 201 participants (49% women) with a mean age of 52, 98 were block randomized to the treatment group and 103 to the control group. The aOR of worsening cartilage defects in the glucosamine group compared to the control group was 0.9 (95% CI 0.55-1.58). The aOR for worsening in BMLs was 0.73 (95% CI 0.50-1.07).

There also was no indication that glucosamine improved uCTX-II (beta = -0.10, 95% CI -0.21-.001). There was a difference in the proportion of drop-outs by group (i.e., 16.5% in the placebo group vs. 5.1% from the glucosamine group, p < 0.01).

Conclusion: This short-term study provided no evidence that glucosamine results in structural benefit in knee OA as assessed using 3T MRI or uCTX.

Disclosure: C. K. Kwoh, The Beverage Institute, 2 ; F. W. Roemer, Boston Imaging Core Lab, LLC, 4 ; M. J. Hannon, None; C. E. Moore, None; J. M. Jakicic, The Beverage Institute, 2, The Beverage Institute, 5 ; A. Guermazi, Synarc, Inc., 1, Boston Imaging Core Lab, LLC, 4, MerckSerono; Facet Solutions , 5, GE HealthCare, 2 ; S. M. Green, None; R. M. Boudreau, None.