Objective: To determine the association of serum asymmetric dimethylarginine (ADMA) with clinical features, laboratory tests, treatment, cardiovascular risk factors, and subclinical atherosclerosis in patients with systemic lupus erythematosus (SLE).
Methods: Serum ADMA concentrations were determined by ELISA, using purified ADMA as a standard. Coronary calcium was measured by helical computerized tomography.
Results: Two hundred patients with SLE participated. Patients had a mean age of 44.3 +/- 11.4 years and were 92% female, 61% Caucasian, 34% African American, 2% Asian, and 2% Hispanic; 18% had elevated ADMA levels. The mean ADMA was 0.31. Significantly higher ADMA levels were found in African Americans (p < 0.001), and were correlated with anti-dsDNA (p < 0.001), anti-Sm (p = 0.005), anti-ribonucleoprotein (p = 0.002), low C4 (p = 0.004), and high erythrocyte sedimentation rate (p < 0.001). ADMA was negatively associated with total cholesterol (p = 0.004). Elevated ADMA was associated with the presence of coronary calcium (p = 0.02).
Conclusion: Elevated ADMA is strongly associated with African American ethnicity, anti-dsDNA, low complement, and prednisone use, all markers of poor prognosis in SLE. It is negatively associated with hyperlipidemia, but positively associated with coronary calcium. Thus, it identifies a subset of SLE patients with normal lipid levels who are at risk for atherosclerosis.