The researchers used three different measures – BMI, WC and dual X-ray absorptiometry (DXA), a technology that more accurately measures body composition – to classify 141 RA patients as obese or not obese. Twenty percent of women and 41 percent of men qualified as obese using BMI (30 or greater), while 32 percent of women and 36 percent of men qualified as obese using WC, and 44 percent of women and 80 percent of men qualified as obese using DXA.

To compensate for the discrepancy between obesity as measured by BMI and the more accurate DXA, Katz and her team recommend lowering the BMI cutoff point to qualify as obese among RA patients from 30 to 26.1 for women and 24.7 for men.

The researchers say the high percentage of overfat patients is troubling because there is a correlation between excess fat and worsening disease symptoms – such as increased pain and fatigue – as well as other health complications.

“Excess fat appears to have a relationship both with disease symptoms and also with cardiovascular risk. That’s why it’s important,” explains Patricia Katz, PhD, the lead study author and a professor in residence of medicine and health policy at the University of California, San Francisco. Adjusting the BMI cutoff would heighten practitioners’ awareness of a patient’s true risk of certain problems.

“For patients, I would get back to the message that you should try to increase your physical activity,” says Katz. “You can accumulate those physical activity minutes in shorter sessions, so you don’t have to go lift weights or go to the gym or to an exercise class. Just go for a walk.”

Weight gain and prednisone in early RA patients

A new study out of the Netherlands takes a closer look at the relationship between low-dose corticosteroid use and weight gain. To find out if prednisone is directly responsible for weight gain, the researchers assigned more than 200 adults with early RA (meaning they’ve had it for less than a year) to one of two groups. For two years, both groups had their disease tightly controlled with a methotrexate-based treatment strategy, but one group was also given a low dose of prednisone (10 mg/day) while the other was given a placebo.

After analyzing the results, the researchers found prednisone did not independently affect body weight. But it did suppress disease activity, which they say could lead to weight gain. Active, or uncontrolled, RA can result in weight loss, possibly due to loss of appetite and/or metabolic changes. Researchers also say it is likely the weight patients gained while on prednisone made up for weight loss they experienced when their disease was active and not well controlled. 

Researchers say high doses of prednisone over long periods can cause weight gain. But they hope their results dispel concerns about relatively low doses of the drug, especially because the patients taking prednisone were found to have less pain and joint damage at the end of the study than the placebo group.

“Patients’ and doctors’ apprehension to use low-dose prednisone in early rheumatoid arthritis, because of its alleged weight-increasing effect, is largely unfounded, but could impede the start of this useful and cheap symptom-controlling and joint-sparing [drug],” says study author Maud S. Jurgens, a PhD candidate of the Utrecht Arthritis Cohort Study Group at the University Medical Center Utrecht, Netherlands.