Being Overweight Could Prevent Your Rheumatoid Arthritis from Going into Remission

Newswise — Being overweight can prevent sufferers of rheumatoid arthritis from going into remission, according to research presented this week at the American College of Rheumatology Annual Scientific Meeting in Boston, Mass.

Rheumatoid arthritis is a chronic disease that causes pain, stiffness, swelling, and limitation in the motion and function of multiple joints. Though joints are the principal body parts affected by RA, inflammation can develop in other organs as well. An estimated 2.1 million Americans have RA, most of them women.

Researchers studied 100 patients with recent onset RA to determine if body mass index (BMI), a calculation based on body fat, height and weight, can contribute to the remission of RA.

Participants were randomly placed on either combination therapy consisting of methotrexate, sulfasalazine, hydroxychloroquine, prednisolone and either placebo or infliximab.

After 12 months of treatment, 58 percent of patients with normal body weight on placebo plus combination therapy were in remission, compared to only 35 percent of those who were overweight and 25 percent of those who were clinically obese (BMI of 30 or greater). The effect of being overweight on ability to achieve remission was not apparent in patients taking combination therapy and infliximab. In this group on infliximab, 45 percent of patients with normal body weight were in remission, while 74 percent of overweight and 55 percent of obese patients were in remission.

"Obesity (increasing body mass index) induces resistance to conventional anti-rheumatic drugs— even in aggressive combination. Infliximab overcomes this resistance, probably due to its direct effect on inflammatory mediators," said Marjatta Leirisalo-Repo, MD, PhD; professor of rheumatology; Helsinki University Central Hospital; department of medicine; division of Rheumatology. "Obese subjects are at increased risk for inflammatory complications due to the production of proinflammatory mediators by the fat tissue."

The ACR is an organization of and for physicians, health professionals, and scientists that advances rheumatology through programs of education, research, advocacy and practice support that foster excellence in the care of people with or at risk for arthritis and rheumatic and musculoskeletal diseases.

http://www.rheumatology.org/annual

Editor's Notes: Dr. Leirisalo-Repo will present this research during the ACR Annual Scientific Meeting at the Boston Convention and Exhibition Center from 4:30 " 6:00 pm ET on Saturday, November 10, 2007, in Grand Ballroom East. Dr. Leirisalo will be available for media questions and briefing at 8:30 am ET on Saturday, November 10 in the on-site press conference room, Room 251. Presentation Number: 2155

Increasing Body Mass Index is Associated with Reduced Rate of Remission in Early Rheumatoid Arthritis

Marjatta Leirisalo-Repo1, Timo Möttönen2, Pekka Hannonen3, Markku Korpela4, Markku Kauppi5, Oili Kaipiainen-Seppänen6, Riitta Luosujärvi1, Hannu Kautiainen5, Reijo Luukkainen7, Toini Uutela8, Eeva Moilanen9. 1Helsinki University Central Hospital, Helsinki, Finland; 2Turku University Central Hospital, Turku, Finland; 3Jyväskylä Central Hospital, Jyväskylä, Finland; 4Tampere University Hospital, Tampere, Finland; 5Rheumatism Foundation Hospital, Heinola, Finland; 6Kuopio University Hospital, Kuopio, Finland; 7Pori Central Hospital, Rauma, Finland; 8Rovaniemi Central Hospital, Rovaniemi, Finland; 9Tampere University, Tampere, Finland

Purpose: NEO-RACo is a double-blind placebo-controlled study on early RA where infliximab (INFL) or placebo (PL) is combined during the first 6 months with methotrexate (MTX max 25 mg/wk), sulfasalazine (SSZ, max 2g/d), hydroxychloroquine (HCQ) and prednisolone (PRED 7.5 mg/d) (= COMBI). We report the role of body mass index (BMI) with respect to the probability of reaching remission by 12 months in patients treated with COMBI + PL or COMBI + INFL.

Patients and methods: We enrolled 100 patients aged <65 y with early active DMARD-naive RA. COMBI was started in all patients targeted to remission. The patients were randomized to receive INFL (3 mg/kg) or PL at weeks 4, 6, 10, 18 and 26. In cases of inefficacy/intolerability, DMARDs were substituted, but it was obligatory to use 3 DMARDs and PRED. We report here the 12-month preliminary results.

Results: One patient withdrew her consent before any intervention. At start, the mean age (SD) of the 99 patients was 46 y (10), median duration (IQR) of symptoms 4 mo (2, 6), mean number (SD) of swollen joints 15 (6), tender joints 20 (10), ESR 33 (22) mm/h and HAQ 1.0 (0.7). 68% were RF+, and 67% female.At 6 months 53% of patients were in remission (COMBI + PL 47%, COMBI+ INFL 58%, ns), and at 12 months 52% (COMBI + PL 45%, COMBI + INFL 58%, ns). At 6 months, 63% of COMBI + PL patients with normal BMI (<25) were in remission, compared to 35% of overweight (BMI 25.0-29.9) and to 25% of obese patients (BMI 30-) (p for linearity=0.023, adjusted for baseline DAS28 and sex). No such association was observed in the COMBI + INFL group: 55%, 68% and 46%, respectively (p=0.88). At 12 months the remissions in COMBI + PL group were 58%, 35% and 25% (p for linearity =0.034) and in the COMBI + INFL group 45%, 74% and 55% (p=0.4), respectively.

The trend for reduced risk for remission in the COMBI + PL group was linear with increasing BMI during the first year. Figure shows predicted probabilities for adjusted (sex and DAS28 at baseline) probit models at 6 months.

Conclusions: RA patients with increasing BMI are less responsive to COMBI treatment. Obesity is characterized by systemic inflammation. Infiximab added on COMBI can overcome this resistance.

[Figure 1 available on request.]

Disclosure Block: M. Leirisalo-Repo, Schering Plough Finland, 2; Centocor, 5; Abbott, 6; Bristol-Myers-Squibb, 6; Roche, 6; T. Möttönen, None; P. Hannonen, None; M. Korpela, None; M. Kauppi, None; O. Kaipiainen-Seppänen, None; R. Luosujärvi, None; H. Kautiainen, None; R. Luukkainen, None; T. Uutela, None; E. Moilanen, None.