It’s no secret that obesity is associated with a higher risk of developing rheumatic diseases and worse outcomes. Three new studies, presented recently at the 2017 Annual Meeting of the American College of Rheumatology, characterize in greater detail the harmful effects of excess weight in people who have rheumatoid arthritis (RA) or axial spondyloarthropathy (axSpA).
In brief, the three studies showed:
- Obesity reduces the chances of reaching RA treatment goals and is associated with greater disease-related disability.
- Overweight and obese patients with RA have more joint inflammation (synovitis) than normal-weight patients do.
- Obese patients with axial spondyloarthropathy (inflammatory arthritis that mainly affects the spine and pelvis) have more symptoms, poorer physical function and worse quality of life compared with normal-weight patients.
Despite strong evidence to support the negative impact of obesity on outcomes in rheumatic diseases, it is challenging for patients to achieve weight loss, experts agree.
“It is a vicious circle in the population we take care of,” says Elena Nikiphorou, MD, lead author of one study and a rheumatologist at Whittington Hospital in London. “Obesity is a risk factor of disease and a consequence of disease and a driver of disease.”
Stefano Alivernini, MD, is the lead author of another of the studies and an academic researcher and consultant at the Institute of Rheumatology of the Catholic University of the Sacred Heart in Rome. “How to target obesity is [with] a multi-disciplinary approach, not just telling people to lose weight,” he says. “Low-grade inflammation [caused by excess weight] has to be switched off – it cannot be ignored.”
RA Treatment Goals, Disability
Researchers led by Dr. Nikiphorou found that higher body mass index (BMI) was associated with lower remission rates and greater disability.
The study used data from two large cohorts in the United Kingdom comprising 2,420 people with early rheumatoid arthritis. At baseline, 37.2 percent of people enrolled in the study were overweight (typically defined as having a BMI between 25 and 29.9), and 21.3 percent were obese (BMI at or above 30). Obesity reduced the likelihood of achieving remission and low disease activity – as measured by the disease activity score (DAS) by 29 percent and 31 percent, respectively. The study also showed that obesity increased the risk of having greater disability (as measured by the health assessment questionnaire, or HAQ) by 63 percent.
“Obesity has a profound negative effect on the achievement of treat-to-target goals in rheumatoid arthritis, both in terms of disease activity and also functional ability. Our study findings make a strong argument for taking note of BMI in people with rheumatoid arthritis and emphasize that obesity should not be ignored in routine secondary care,” says Dr. Nikiphorou.
Joint Damage in RA
In a separate study, Italian researchers led by Dr. Alivernini looked at the effect of overweight/obesity on joint damage. Study participants were 125 RA patients in three different groups: those who were never treated, those with an inadequate response to treatment, and those in stable remission after treatment. Across the three groups, between 56 percent and 59 percent of the patients were overweight/obese, the others were of normal weight. A biopsy of synovial tissue, which lines the joint, was taken from all the patients, and all were analyzed for immune system markers associated with inflammation.
“We found that overweight/obesity status significantly influences joint inflammation at disease onset before starting drug treatment, and remission was significantly less likely at one year in patients who were overweight/obese compared to normal-weight people,” says Dr. Alivernini. “Even among patients who do achieve clinical remission on drug treatment, those who are overweight/obese are more likely to have residual joint inflammation compared with normal-weight people.”
He explains, “We believe that these findings are important and that they support the notion that BMI should be tracked, even in rheumatoid arthritis patients who have the best treatment outcomes. Since body weight is a modifiable factor, a standard multidisciplinary approach for weight loss with a rheumatologist, nutritionist and psychologist is advised to increase disease control.”
Obesity and Spondyloarthropathy
A third study analyzed data from 683 patients with chronic inflammation of the sacroiliac joint and spine who were enrolled in the Ankylosing Spondylitis Registry of Ireland (ASRI). Researchers found that patients who were overweight (38 percent) or obese (28.4 percent) tended to be older, had longer duration of disease and had more comorbidities (including hypertension and elevated lipid levels) than people in the study of normal weight. The study showed obesity was an independent predictor of significantly higher disease activity and worse physical function.
“We found that obese patients had more severe disease than their normal-weight and overweight counterparts, with higher measures of disease activity, impaired quality of life, disability, and [impaired] function, as well as worse spinal mobility,” says lead author Geraldine Fitzgerald, MD, a rheumatologist at St. James’ Hospital in Dublin, Ireland. “We need more research on the effect of losing weight in people with this disease. But rheumatologists should include strategies for actively controlling weight when devising treatment plans for axial spondyloarthropathy patients.”
Dr. Fitzgerald says one surprise in this study was the high percentage of overweight and obese patients. “We tend to think of patients with axial spondyloarthropathy as being normal weight or thin,” she notes. “Over two-thirds of the people in the study had an unhealthy weight, and only 32 percent had a healthy BMI.”
Obesity: International Challenge
“These studies from Ireland, Italy, and the U.K. show that obesity is an international health issue,” says Margaret Tsai, MD, a rheumatologist at the Cleveland Clinic in Ohio. “The three abstracts support each other, showing that obesity is an independent factor that negatively impacted people with axial spondyloarthropathy and rheumatoid arthritis. We as clinicians need to add weight management treatment early in our treatment plans.” Dr. Tsai, who was not involved in any of the studies, moderated a press conference where these studies were discussed.
“Obesity and weight loss are sensitive topics for patients. A multipoint program including nutrition education, low impact weight-bearing exercise, and regular office visits that provide support and feedback may be more effective for treating obesity. Clearly, obesity is a priority that needs to be addressed by the entire medical community,” says Dr. Tsai.
But achieving weight loss is a big challenge, acknowledges Dr. Nikiphorou. “Identifying the best strategy is important and it has to be personalized to each individual’s needs and abilities,” she says. “The results of these three studies suggest that obesity is a problem that should not be ignored, as it has a profound effect on outcomes.”
Author: Alice Goodman
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