Atherosclerosis may be considered an inflammatory disease characterised by the development of atherosclerotic plaques and ischaemic cardiovascular events. Increased prevalence of cardiovascular morbidity and mortality due to (premature) atherosclerosis has been observed in patients with autoimmune diseases like rheumatoid arthritis (RA), systemic lupus erythematosus (SLE) and Wegener's granolumatosis. This increased prevalence cannot be explained by the presence of the traditional cardiovascular risk factors such as hypertension, hyperlipidaemia, diabetes mellitus and smoking. Therefore, other risk factors must be present in patients with systemic autoimmune disease. Although the mechanisms have not been fully unravelled, endothelial cell (EC) activation through autoantibodies seems to be one of the factors involved. EC activation results in EC dysfunction. It is supposed that chronic EC dysfunction, as present in patients with systemic autoimmune disorders, contributes to the development of premature atherosclerosis and results in an increased prevalence of cardiovascular disease.