Objectives To explore the influence of body composition and abdominal adiposity on endothelial dysfunction and radiological damage in Rheumatoid Arthritis (RA) patients.
Methods A total of 100 patients, 54 RA patients and 46 controls, adjusted for sex, body mass index (BMI), age and comorbidity, were included. Total body composition was measured by dual energy X-ray absorptiometry; total and regional lean mass, fat mass, fat free mass index (fat free mass/m2) and fat mass index (fat mass/m2) were established. Quantification of visceral and parietal abdominal fat area was determined using magnetic resonance imaging, as well as visceral/parietal fat index. Endothelial dysfunction was assessed by brachial artery flow-mediated dilatation (FMD) as the dilator response to 5 minutes distal cuff occlusion and after sublingual nitroglycerine administration, and the Sharp Score defined radiological damage. The 28-joint DAS (DAS-28) and disability using HAQ (Health Assessment Questionnaire) scores, erythrocyte sedimentation rate (ESR) and C-reactive protein were collected. Multivariate analysis was performed to compare body composition between controls and patients and the relationship between those and endothelial dysfunction and radiological damage, everything adjusted for demographic and comorbidity variables.
Results In the univariate analysis RA patients showed less flow-mediated dilatation (5.9 vs 9.8 mm, p=0.03). Similarly, fat free mass index was higher in patients than in controls (beta coefficient 0,94 (CI95% 0,08-1,80), P=0,03) after adjusting for BMI, sex and age; on the other hand fat mass index tended to be higher in patients than in controls (beta coefficient 2,51 (CI95% -0,82-5,84), p=0.13). Parietal and visceral abdominal fat values did not show differences between controls and patients. Fat mass, lean mass and abdominal fat did not correlate with DAS-28, HAQ, ESR or CRP. Parietal abdominal fat through resonance imaging in RA patients showed a negative relation with flow-mediated dilatation (beta coefficient -0.045 mm FMD/cm2 parietal area, p=0.02) after adjusting for BMI. This relation was not found with visceral abdominal fat. Radiological damage was negatively correlated with total bone mass (beta coefficient -1,13, CI95% -2,05-0,22, p=0.02) and showed a negative trend to do it also with total lean mass (beta coefficient -1.11 CI95% 2,42-0,21, p=0,09).
Conclusions Changes in body composition take place in RA patients. These changes can be related to the endothelial dysfunction and radiological damage that occurs in this disease.
Disclosure of Interest None Declared