Objective: To analyze endothelial function in systemic lupus erythematosus (SLE), and its relationship with disease activity and subclinical arteriosclerosis.
Methods: We studied a group of 26 patients with SLE and 21 age- and sex-matched controls. None of the patients or controls had had any ischemic event. Data were recorded on medical history, anthropometrics, prior treatment and the lupus activity index (LAI). Endothelial function was quantified by flow-mediated dilatation in the brachial artery. The presence of subclinical arteriosclerosis was assessed by the average intima-media thickness (IMT) on carotid ultrasound.
Results: The patients and the controls had a similar degree of carotid IMT (0.58+/-0.08 mm vs. 0.57+/-0.07 mm, NS) and a similar prevalence of carotid plaque (27% vs. 24%, NS). However, the SLE patients had worse endothelial function than the controls (FMD 12.4+/-4.4% vs. 16.9+/-5.5%, p<0.05). This difference remained after adjusting for age, smoking, body mass index, waist circumference, total cholesterol, triglycerides, HDL cholesterol, apolipoproteins A-1 and B100 and postmenopausal status. A significant association was found in the SLE patients between FMD and LAI (Spearman Rho -0.462, p<0.05).
Conclusion: SLE-associated endothelial dysfunction is present in patients who have no prior ischemic events and with the same degree of subclinical arteriosclerosis as controls. The endothelial dysfunction is significantly associated with the degree of disease activity.