Abdominal adiposity, especially visceral adiposity, is emerging as a recognized cardiometabolic risk factor. This study was undertaken to investigate how abdominal fat is distributed in rheumatoid arthritis (RA), and its RA-related determinants.
Men and women with RA were compared with non-RA controls from the Multi-Ethnic Study of Atherosclerosis. Participants underwent anthropometric studies and quantification of visceral and subcutaneous fat areas (VFA and SFA) using abdominal computed tomography.
A total of 131 RA patients were compared with 121 controls. Despite similar body mass index and waist circumference between the RA and control groups, the adjusted mean VFA was 45 cm2 higher (+51%) in male RA patients versus male controls (P = 0.005), but did not significantly differ by RA status in women. The adjusted mean SFA was 119 cm2 higher (+68%) in female RA patients versus female controls (P < 0.001), but did not significantly differ by RA status in men. Elevated VFA (≥75th percentile) was associated with a significantly higher adjusted probability of having an elevated fasting glucose level, hypertension, or meeting the composite definition of the metabolic syndrome in the RA group compared with controls. Within the RA group, rheumatoid factor seropositivity and higher cumulative prednisone exposure were significantly associated with a higher mean adjusted VFA. Higher C-reactive protein levels and lower Sharp/van der Heijde scores were significantly associated with both VFA and SFA.
The distribution of abdominal fat differs significantly by RA status. Higher VFA in men with RA, and the more potent association of VFA with cardiometabolic risk factors in men and women with RA, may contribute to cardiovascular risk in RA populations.