SAN DIEGO — Weight loss can profoundly improve function and pain in patients with knee osteoarthritis.
And even relatively minor weight loss of 15 lb in a moderately obese person can produce more improvement than an NSAID, Susan J. Bartlett, Ph.D., said at the annual meeting of the American College of Rheumatology.
“The more you lose, the greater the improvement,” said Dr. Bartlett, a rheumatologist at Johns Hopkins University, Baltimore.
Dr. Bartlett reported on a trial in which 48 patients who had knee osteoarthritis meeting American College of Rheumatology (ACR) criteria for significant impairment and were mildly or moderately obese (average body mass index 33 kg/m
The weight loss program consisted of 17 weekly classes on weight loss. Participants were encouraged to adopt a diet of 1,200–1,400 calories a day for women and 1,600–1,800 calories a day for men and to walk for exercise, gradually increasing to 30 minutes daily.
At intervention's end, patients had lost an average 15 lb and had a mean 49% decrease in their Western Ontario and McMaster Universities (WOMAC) Osteoarthritis Index total scores. WOMAC pain scores declined by a mean 39%, stiffness scores by 45%, and function scores by 49%.
Those improvements are greater than those reported for NSAID treatment in a recent trial comparing various COX-2 inhibitors with acetaminophen (J. Rheumatol. 2005;32:1093–105), Dr. Bartlett said.
The controls lost no weight and had no improvement in WOMAC.
The ACR's existing recommendations advise weight loss for osteoarthritis patients who are overweight. However, it has not been clear how much weight loss is needed to make a difference before this study, Dr. Bartlett said.
Findings from this study, though based on small numbers, suggest that the association between weight loss and WOMAC score approaches a dose/response, with even minimal loss producing improvement, Dr. Bartlett said.
She noted that research has suggested that there is a 9%–13% increased risk of a person developing knee osteoarthritis for every 2 lb of weight they gain.