High or Low Weight May Make Rheumatoid Arthritis Worse

Data gathered from the Rheumatoid Arthritis Support Network, known as RASN, shows that the disease affects over 1.3 million individuals in the United States. Risk factors associated with rheumatoid arthritis (RA) include genetics, hormones, environmental risk factors, as well as lifestyle risk factors, such as obesity and unexplained weight loss. “Weight plays an important role in joint stress, so when people are very overweight, it puts stress on their joints, especially their weight-bearing joints, like the knees and the hips,” said Eric Matteson, chair of the rheumatology division at the Mayo Clinic in Rochester, Minnesota. The more weight that is on a joint, the more stressed it becomes and the more likely it will erode and become damaged.

Yet, another rather confusing finding about fat in RA is that quite a few studies have found that individuals with RA who are obese have less joint damage than thinner individuals with RA. “This may due to the action of adiponectin, an inflammatory protein produced by fat cells, that is actually found in higher levels in leaner people with RA,” said Dr. Jon T. Giles, assistant professor of medicine at Columbia University in New York City. However, these findings do not indicate the being obese will prevent joint damage in RA. “In fact, you are still at risk for your arthritis to advance more rapidly in your weight-bearing joints simply because of the biomechanical forces that come into play,” said Dr. Matteson.

The well-known role of obesity in RA

Over 60% of people with RA are overweight or obese. In such individuals, excess body fat can lead to complications, such as heart disease, stroke, and other conditions. Fat cells, also known as adipocytes, release proteins called cytokines that trigger inflammation throughout the body. “Fat, or adipose, tissue is a source of many of the same inflammatory cytokines that are produced by inflamed joint tissue in people with inflammatory arthritis,” said Dr. Giles. Therefore, the more pounds an individual with RA adds on, the more of these proteins that circulate within the body. This, in turn, leads to aggravation of the inflammation that is already present within the joints, more pain, and worsened overall health.

Up & down: the effect of weight on RA

According to findings from a new research study published in the journal Arthritis Care & Research, obesity may accelerate and aggravate the symptoms of RA and unexplained weight loss may also increase the risk for disability among these individuals. “While patients and rheumatologists may be focused mostly on disease activity, we should also consider this common condition (obesity), which can contribute to problems that are usually attributed to the arthritis itself,” said Dr. Joshua Baker, author of the study and assistant professor of medicine at the University of Pennsylvania’s Perelman School of Medicine. In addition, unexplained or unintentional weight loss causes individuals with RA to become weak and worsen over time, leading to poor health and an increased risk for developing disability.

Read on to learn how RA affects those who are above or below ideal weight.