Our OrthoBuzz report of the “near-death” of glucosamine/chondroitin may have been premature, according to a recent study published online in the Annals of the Rheumatic Diseases. The randomized, double-blind study assigned 606 patients with knee osteoarthritis and moderate-to-severe pain to receive either glucosamine (500 mg) and chondroitin (400 mg) three times a day, or one daily dose of the COX-2 inhibitor celecoxib (200 mg).
The study was designed to discern noninferiority between the supplements and celecoxib, and the results over six months showed equivalent benefits in both groups. WOMAC measures of pain decreased by 50.1% in the supplement group and 50.2% in the celecoxib group. Both groups also showed a >50% reduction in the presence of joint swelling, and adverse events were low in both groups.
One thing readers may want to consider when mulling over these results: The study was sponsored by the manufacturer of the glucosamine/chondroitin product used in the trial, and all authors disclosed financial relationships with that manufacturer.
An additional perspective on these and other glucosamine/chondroitin findings comes from JBJS Deputy Editor for Research Tom Bauer, MD, an ultra-marathon runner who’s free of arthritis symptoms and does take glucosamine/chondroitin supplements. Dr. Bauer emphasizes the distinction between preventing osteoarthritis and treating it. “Most published studies in humans, like this recent one, have tested glucosamine/chondroitin in patients with pre-existing osteoarthritis,” he said. “It’s a tall order to expect any oral medication to induce actual restoration of the articular surface, so I’m eager to see a decent chondroprotective study of these supplements in athletes who do not have osteoarthritis.”
In a recent Annals of Rheumatic Diseases study, Australian researchers reported that levels of circulating leptin—a hormone that influences body weight and regulates some inflammatory processes—are negatively associated with changes in knee-cartilage thickness.
This prospective cohort study of 163 randomly selected patients (mean age of 63) used MRI to assess knee-cartilage thickness and radioimmunoassay to measure serum leptin levels at baseline and again after an average of 2.7 years. Cross-sectionally, leptin levels were negatively associated with cartilage thickness at femoral, medial tibial, lateral tibial, and patellar sites, after researchers adjusted for age, sex, BMI, and disease status. Longitudinally, baseline levels and changes in leptin over time were associated with greater differences in tibial-cartilage thickness.
The authors speculate that leptin may have a catabolic effect on cartilage that contributes to the development of osteoarthritis (OA), and that decreases in leptin levels associated with weight loss may help explain the clinical improvement in patients with knee OA who lose weight.
According to a recent study in the Annals of the Rheumatic Diseases, women who take hormone replacement therapy (HRT) for at least 6 months after a total hip or knee replacement may cut the risk of revision surgery by almost 40%. This potential reduction in revision rate becomes even more impressive when one considers estimates that put the number of knee replacements in the US at close to 3.5 million annually by the year 2030.
The study, which compared joint-replacement outcomes in 2,700 female HRT users with outcomes in 8,100 matched nonusers, found no difference in revision rates relative to HRT use before surgery.
Elena Losina, PhD., JBJS deputy editor for methodology and biostatistics, called this study “well designed and executed” in an article in Arthritis Today. But she was quick to add that “to consider these results more definitively in clinical practice, they need to be confirmed and reproduced in a multicenter randomized controlled trial.”