Weight Loss Improves RA Disease Control in Obese Patients

SAN FRANCISCO, CA—Obese patients diagnosed with rheumatoid arthritis (RA) can improve disease control by losing weight, according to a study reported at the 2015 ACR/ARHP Annual Meeting.

A controlled diet in patients who are obese (BMI >30kg/m²) allows them to “obtain better disease control without changing the treatment of RA,” reported Stefano Alivernini, MD, of the Division of Rheumatology, Institute of Rheumatology, Catholic University of the Sacred Heart in Rome, Italy, on behalf of lead study author Elisa Gremese, MD, and coauthors.

A weight loss of more than 10% was found to result in disease remission “in a significant percentage of patients,” reducing the need to increase or modify therapy, the authors noted.

Obesity is “a systemic, low-grade inflammatory state,” with adipose tissue releasing pro-inflammatory cytokines. A potentially preventable risk factor for RA, obesity is associated with RA onset, disease severity, and poor response to therapy.

To evaluate weight loss-associated outcomes among obese patients diagnosed with low-to-moderate-disease-activity RA (Disease Activity Scores [DAS] of 1.6 to <3.7), the authors enrolled 72 consecutive patients in stable therapy with conventional disease-modifying antirheumatic drugs (cDMARDs) or biologic DMARDs (bDMARDs) for at least 12 weeks, in a controlled nutritional intervention.

All patients followed a nutritionist-guided dietetic regimen, with the goal of >5% weight loss compared with baseline at 6 months. RA therapy remained unchanged. Patients were evaluated by the rheumatologist and nutritionist every 2 months and at each clinical visit. Laboratory and ACR/EULAR core data were registered. Disease activity was evaluated by DAS on 44 joints and using the Simplified Disease Activity Index (SDAI).

The 72 patients were mostly (84.7%) female; median age was 56.2 ± 12.5 years and 25% were current smokers. Disease duration was 7.8 ± 8.4 years. A total of 70.8% were seropositive, with a baseline DAS of 2.9 ±0.8 and a baseline BMI of 35.2 ± 5.0).

Forty-two patients (41.7%) were undergoing cDMARD-only therapy and 30 (41.7%) were administered bDMARD therapy, with or without cDMARD.

Of the 63 patients with RA who reached the 6-month follow-up, mean reduction in body weight was 6.7 ± 4.7kg (vs. 7.3 ± 6.0% at baseline; P<0.01). Mean reduction in DAS was 0.8 ± 1.0 (vs. 2.0 ± 0.7 at baseline; P<0.001), the authors reported.

“Moreover, after 6 months of controlled dietary regimen, RA patients showed a significant improvement of SDAI with respect to baseline (P<0.01),” Dr. Alivernini noted. This improvement was also observed for tender (P<0.01)and swollen (P<0.01) joint count, systemic inflammatory parameters (ESR P=0.001; CRP P=0.001), GH (P<0.01), VAS pain (P<0.01), and HAQ, “without any change of RA therapy” or need for corticosteroids.

When patients were divided by percentage of weight loss at 6 months, the 40 (63.5%) who had a >5% reduction obtained higher rates of DAS remission than patients with a weight reduction of <5% (35.0% vs. 9.1%; P=0.03), as well as SDAI remission (34.2% vs. 4.8%, P=0.01).

The difference was “even more significant” with a weight reduction of >10%; at 6 months, DAS remission was 55.6%, compared with 13.6% of patients who did not lose >10% of their baseline weight (P<0.01), the authors found.

Results were similar between patients receiving cDMARD-only and bDMARD treatment.

“The effects of weight loss based on a nutritional intervention, and so applicable at the population level, on the RA disease course appears to be crucial in terms of potential clinical and pharmacoeconomics perspectives,” the authors concluded.