Relation between body mass index and radiological progression in patients with rheumatoid arthritis.
OBJECTIVE
To determine if there is an influence of body mass index (BMI) on the radiological progression in early and longer duration rheumatoid arthritis (RA).


METHODS
Fifty-four patients with RA were observed in a progressive 2 year followup for radiological progression of joint damage. At the beginning of study, 27 (50%) patients had a duration of complaints less than 6 months, grouped as early RA. BMI at the beginning and end of the study were monitored, together with HLA-DRB1 alleles, initial joint erosions, duration of disease, age, sex, erythrocyte sedimentation rate (ESR), and C-reactive protein (CRP). Outcome was defined as radiographic damage according to yearly increase of Larsen score.


RESULTS
Increased radiographic joint damage of patients was significantly correlated with lower BMI at the beginning of the study (r = 0.363, p < 0.05), the presence of initial joint erosions (r = 0.341, p < 0.01), ESR (r = 0.315, p < 0.05), and CRP at study entry (r = 0.427, p < 0.01). Patients with an increase of Larsen score > or = 5.8/year were found to have a lower weight at the beginning of their complaints (BMI 24.8 +/- 4.7 vs 27.8 +/- 3.8; p < 0.05) as well as after the time of observation (BMI 24.6 +/- 3.7 vs 27.6 +/- 4.9; p < 0.05). Stepwise logistic regression analysis revealed a BMI < 27 at the beginning of disease (beta = 2.04, p = 0.003, odds ratio = 7.69), the presence of HLA-DR4 shared epitope (beta = 1.76, p = 0.015, OR 5.82), and joint erosions at study entry (beta = 1.56, p = 0.044, OR 4.78) as significant predictors for rapid joint damage.


CONCLUSIONS
Together with the presence of HLA-DR4 shared epitope and erosive disease at study entry, a low BMI at the beginning of RA was found in association with higher radiographic progression in RA. Accordingly, BMI could be of interest as a sensitive and inflammation-independent predictor for radiological outcome of RA.
Kaufmann
Jörg
J
Department of Internal Medicine IV, Division of Rheumatology and Osteology, Friedrich Schiller University of Jena, Erlanger Allee 101, 07740 Jena, Germany. jeorg.kaufmann@med.uni-jena.de
Kielstein
Volker
V
Kilian
Susann
S
Stein
Günter
G
Hein
Gert
G
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001172:Arthritis, Rheumatoid / Q000000981:diagnostic imaging* / Q000276:immunology / Q000473:pathology* / Q000503:physiopathology; D001175:Arthrography; D015992:Body Mass Index; D018450:Disease Progression; D000939:Epitopes; D005260:Female; D015804:HLA-DR4 Antigen / Q000276:immunology; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged
D000939:Epitopes; D015804:HLA-DR4 Antigen