Body fat percent and fat distribution parameters in rheumatic diseases

Alterations in body composition in chronic rhematologic disorders have been associated with decreased strength, altered energy metabolism and immunologic compromise and may provide a useful indicator of the severity of the disease. However, results of anthropometric parameter studies have been equivocal. The purpose of this study, was to compare body composition parameters of patients with rheumatoid arthritis (RA) and ankylosing spondylitis (AS) with those of healthy controls. Mean age, height, weight and body mass index (BMI) of patients with RA were not found to be different from those of the controls. BMI, body fat percent (BFP) were found to be high in patients with AS, but the differences between this two parameters of AS patients and controls were not statistically significant. Mean BFP of patients with RA was higher than the control subjects, but only the difference between female patients with RA and controls was statistically significant. Mean lean body mass (LBM) was slightly lower in male and female patients with RA compaired to the healthy controls. LBM of AS patients was found to be similar with that of the controls. Upper/lower body fat ratio (U/L BFR) and central/peripheral body fat ratio (C/P BFR) were higher in male patients with RA, but there were no differences between patients and controls. U/L BFR and C/P BFR body fat ratios were higher in AS patients. But, only the differences between C/P body fat distribution of AS patients and control subjects was statistically significant. The results obtained from this preliminary report show some anthropometric parameters of RA and AS patients can differ from those of the healthy controls. Future investigations are needed to determine the metabolic alterations causing the changes in body composition.