Obesity linked to reduced remission rates, decreased mortality risk in RA
Obesity and weight can affect remission and mortality among patients with rheumatoid arthritis, according to a pair of recent studies.
In a study published in Arthritis Care & Research investigating the potential impact of weight on remission in the first 3 years following an RA diagnosis, Vivian Bykerk, MD, BSc, FRCPC, of the Hospital for Special Surgery and Weill Cornell Medical School, in New York, and colleagues found that obese patients were 47% less likely to experience sustained remission, compared with those with healthy BMI, despite receiving similar treatments. Overweight patients were 25% less likely to remain in remission.
“This study shows a direct relationship between being overweight and obese and a reduced chance of getting into a prolonged remission in patients being treated for RA,” Bykerk told Healio Rheumatology. “It supports the importance of working on weight loss to help patients get the best possible control of their disease.”
Bykerk and her fellow researchers studied data from the Canadian Early Arthritis Cohort, a multicenter observational trial of patients with early RA who were treated by rheumatologists using guideline-based care. Of the 982 participants, 32% had a healthy BMI, while 35% were overweight and 33% were obese. Within 3 years, 36% of patients experienced sustained remission.
“These findings are significant to patients and their rheumatologists since rates of overweight and obesity continue to rise,” Susan Goodman, MD, another co-author from the Hospital for Special Surgery and Weill Cornell Medical School, told Healio Rheumatology. “We found that a high proportion of newly diagnosed RA patients who are overweight or obese and who may have disease that is harder to treat. For people with RA who haven’t had an adequate response to treatment, this may be another factor to consider.”
According to the Bykerk, the research represents the largest study demonstrating the negative impact of excess weight on RA disease activity. She added that the findings support a “call to action” to better identify and address this risk in patients.
“Obesity is becoming an epidemic throughout the world and is impacting outcomes of chronic diseases such as RA,” Bykerk said. “Health providers need to give patients the message that managing weight is an important part of their treatment and actively help them find professionals who can work with them to reduce their weight. It is likely that obesity is contributing to the high costs of treating these therapies. We still need more evidence to show better disease control over time as weight goes down. We are not sure yet how obesity mediates the negative effects on this disease but there is evidence that it does so directly by impacting the inflammatory response but also by contributing to associated comorbid diseases which in turn affect feelings of general health, activity, mobility.”
In another study, published in Arthritis & Rheumatology, Jeffrey Sparks, MD, MMSc, of Brigham and Women’s Hospital and Harvard Medical School, in Boston, and his team of researchers found that severe weight loss during the early RA period was associated with an increased risk for mortality — in women both with and without RA. The researchers had been investigating the so-called “obesity paradox,” which describes the apparent association between obesity and a decreased risk for early death. According to this explanation, patients with longstanding RA who reached normal or underweight BMI have higher observed mortality and are relatively less healthy than RA patients who maintained obesity or overweight.
According to the researchers, their findings extend prior observations by including non-RA patients and finding no protective association between weight gain and mortality. This, they said, argues against an RA-specific obesity paradox for mortality.
“Our findings are significant because they show that weight gain did not offer a benefit for mortality among patients with RA,” Sparks told Healio Rheumatology. “Prior studies suggested that patients with RA and obesity were at lower risk of death.”
To investigate the issue, the researchers analyzed the effect of weight change in 902 women diagnosed with early RA in the Nurses’ Health Study, as well as 7,884 matched women without RA.
According to the researchers, women with RA had higher mortality rates than women without RA. Among women with RA, 41% died during an average follow-up of 17 years after the early RA period. Among women without RA, 29.2% died during an average follow-up of 18.4 years. In both groups, women who had severe weight loss, defined as losing more than 30 pounds, had the highest mortality rates after the early RA period. Meanwhile, weight gain in the early RA period was not associated with mortality for either group.
According to Sparks, the study is the first to focus on weight change around RA diagnosis and risk of death, rather than weight change in patients who had RA for many years.
“We demonstrated that mortality risk was related mostly to severe weight loss, which was likely unintentional and related to serious underlying diseases,” he said. “Further, we demonstrated that weight change for women with RA and comparators without RA had a similar effect on mortality. These findings argue that there is not an RA-specific mortality risk based on either weight loss or gain. While we found that weight loss was associated with increased mortality, this was most pronounced in the severe weight loss group, so was likely due to unintentional weight loss. Clinicians should still encourage healthy weight loss strategies to patients with RA.” – by Jason Laday
Disclosure: Bykerk and Goodman report no relevant financial disclosures. Sparks reports funding from the Scientist Development Awards. See full studies for additional author disclosures.