Is the frequency of metabolic syndrome higher in South Korean women with rheumatoid arthritis than in healthy subjects?

To compare the frequency of metabolic syndrome (MetS) and magnitude of insulin resistance, measured by the homeostatic model assessment of insulin resistance (HOMA-IR), between South Korean women with rheumatoid arthritis (RA) and healthy subjects, and to evaluate risk factors for MetS and increased HOMA-IR in patients with RA. In a cross-sectional setting, 84 female patients with RA and 109 age-matched healthy female subjects were consecutively recruited at a university-affiliated rheumatology center in South Korea. MetS was defined according to the Third Report of the National Cholesterol Education Program's Adult Treatment Panel (NCEP-ATP III) 2004 criteria. The frequency of MetS did not differ significantly between patients with RA (19%) and healthy subjects (15.6%, p = 0.566), although patients with RA had a higher HOMA-IR compared with healthy subjects (p < 0.001). Patients with RA met the NCEP-ATP III 2004 criteria for high blood pressure more often than healthy subjects (44% vs. 19.3%, p < 0.001), and low high density lipoprotein cholesterol was more prevalent in healthy subjects (33%) than in patients with RA (14.3%, p = 0.004). Although no obvious risk factors for the presence of MetS were identified in patients with RA, higher serum C-reactive protein and disease activity score assessed using the 28-joint count for swelling and tenderness-erythrocyte sedimentation rate significantly contributed to a higher HOMA-IR. Despite their increased insulin resistance, South Korean women with RA did not have a significantly higher frequency of MetS compared with that in healthy subjects.