Researchers examined data on more than 25,000 patients with RA. Most were overweight or obese when they joined the study. Those who were severely obese were more likely to report some disability at baseline.
Worsening disability “was not explained by worse disease activity,” says lead study author Joshua Baker, MD, of the University of Pennsylvania and the Philadelphia VA Medical Center. “This suggests that obesity causes disability in patients with rheumatoid arthritis and provides yet another reason for patients to try to take off a few pounds.”
The study, published April 29 online in Arthritis Care & Research, wasn’t designed to prove whether or how obesity might directly contribute to disability in RA patients.1 Still, the results suggest that RA patients may feel better if they lose weight, even if it’s not enough to stop being obese, says Dr. Axel Finckh, a researcher at Hopital Beau Sejour in Geneva, Switzerland, who wasn’t involved in the study.
“I would say to my patients that they should aim for a slow, progressive weight loss, associated with increased physical activity, rather then aiming for unrealistic aims such as reaching normal weight,” Dr. Finckh says by email.
Although obesity may lead to worsening disability for RA patients, it’s also possible that some people with the immune system disorder may become obese as a result of this disease, notes Dr. Predrag Ostojic, a researcher at the University of Belgrade in Serbia who was not involved in the study.
“Due to disability and chronic pain, patients with RA are less active, and inactivity may contribute in gaining weight,” Dr. Ostojic says by email. “On the other hand, obesity may cause joint damage independently of rheumatoid arthritis, by excessive joint loading and accelerated degeneration of the joint cartilage (osteoarthritis), especially on lower limbs and spine.”
“Any weight reduction will have positive effect on functional ability,” Dr. Ostojic adds. “Healthy weight is ideal, but overweight is also an acceptable target, especially in rheumatoid arthritis patients who are severely obese.”
- Baker JF, England BR, Mikuls TR, et al. Obesity, weight loss, and progression of disability in rheumatoid arthritis. Arthritis Care Res (Hoboken). 2018 Apr 29. doi: 10.1002/acr.23579. [Epub ahead of print]