Psoriasis is a common, chronic inflammatory and frequently severe skin disease. Recent epidemiologic studies have documented an increased cardio-vascular mortality in psoriasis patients. Our own work focuses on endothelial cells as mediators for the development of inflammatory infiltrates and more recently as a victim of injury caused by infiltrating cells. In this context, we have measured systemic effects of this seemingly cutaneous inflammation, which results in a metabolic state much like that in patients developing diabetes mellitus and insulin resistance. The latter is an important pathomechanism causing endothelial cell dysfunction and subsequently cardiovascular diseases such as myocardial infarction or stroke. Co-morbidities observed in psoriatic patients therefore represent complications of the accompanying systemic inflammation and are likely to be mediated through the mechanism of insulin resistance. As psoriasis is a risk factor for cardiovascular diseases, its adequate management must include the treatment of other known risk factors. Dermatologists should discuss the elevated cardiovascular risk with their psoriasis patients and encourage them not to smoke and to normalize their body weight.