Impaired endothelial function in systemic lupus erythematosus

Systemic lupus erythematosus (SLE) patients suffer from excess cardiac deaths due to accelerated atherosclerosis. Endothelial dysfunction is a marker of early atherosclerosis. We tested the hypothesis that SLE patients have impaired endothelial function and assessed the relationship between endothelial function and clinical outcome over the subsequent five years. Thirty-six female SLE patients were compared with 22 healthy age and sex matched controls. Endothelial dependent vasodilatation (EDD) was assessed at the brachial artery in response to shear stress. Endothelium-independent dilatation induced by glyceryl trinitrate was also measured. Patients were followed for up to five years and the development of damage in the cardiovascular and other systems recorded. SLE patients showed significantly impaired endothelial function (median EDD 5.6%, IQR 3.1-7.2%) compared with healthy controls (median EDD 8.0%, IQR 6.3-9.3%; P = 0.001). Endothelium independent dilatation did not differ between the two groups. Endothelial function was significantly worse in postmenopausal compared with premenopausal women (median EDD 6.6%, IQR 3.9-7.8% versus 3.1%, IQR 2.6-5.1%; P = 0.016). Total cholesterol was inversely correlated with endothelial function in SLE patients (Spearman correlation r = -0.422, P = 0.025). There was no relationship between endothelial function and the development of damage in any organ system, including the cardiovascular system during patient follow-up. Patients with SLE have impaired endothelial function. In the small number of patients studied impaired endothelial function was not associated with a worse cardiovascular outcome over five years.