Weighty Concerns in Rheumatoid Arthritis

May 1, 2018

Both weight loss and obesity are associated with worsening disability in RA.

Adults with rheumatoid arthritis who are severely obese experience more rapidly progressive disability than those who are overweight, a recent study found. Weight loss after study enrollment was also associated with worsening disability, possibly as a sign of frailty. The results appear in Arthritis Care & Research.

The study
To examine the effects of obesity in patients with rheumatoid arthritis over time, Joshua Baker, MD, MSCE, of the Perelman School of Medicine at the University of Pennsylvania, and his colleagues looked at data on 23,323 patients with rheumatoid arthritis from the National Data Bank of the Rheumatic Diseases and 1697 from the Veterans Affairs RA registry.

The results
Severe obesity was associated with more rapid progression of disability. This was not explained by arthritis-related factors, such as the C-reactive protein level and the swollen joint count. The researchers also found that patients who lost weight tended to become disabled more quickly, especially those who were already thin.

“We believe that this is because when people get older and acquire illnesses, they tend to lose weight. Therefore, the important weight loss in this study is unintentional,” said Dr Baker. “So, this study suggests that patients with rheumatoid arthritis and obesity would benefit from intentional weight loss through a comprehensive management strategy; however, when we see that someone is losing weight without trying, it’s probably a poor prognostic sign, especially if they are already thin.”

Clinical implications
The findings are especially relevant in light of the rising rates of obesity in recent years. “While patients and rheumatologists may be focused mostly on disease activity, we should also consider this common condition, which can contribute to problems that are usually attributed to the arthritis itself,” said Dr Baker. “In addition, unintentional weight loss should alert us that the patient may be becoming frail and is at risk for developing new disability.”

References:

Baker JF, England BR, Mikuls TR, et al. Obesity, weight loss, and progression of disability in rheumatoid arthritis. Arthritis Care Res. April 30, 2018. DOI: 10.100/acr.23579. [Epub ahead of print]

Obesity may hasten disability in patients with rheumatoid arthritis [press release]. Hoboken, NJ: John Wiley & Sons, Inc.; April 30, 2018.