RESUMEN
Metabolic syndrome, a "cluster" of metabolic disorders including hypertension, increases the cardiovascular risk, and insulin resistance plays a key role in its pathogenesis. In this syndrome antihypertensive treatment with beta-blockers is underused because of their adverse metabolic effects. The aim was to review the evidences supporting the reasons for underusing beta-blockers in hypertensive patients with metabolic syndrome. A review of Literature has been carried out via PubMed from 1998 to 2008: most of beta-blockers have adverse effects on insulin sensitivity, carbohydrate and lipid metabolism, and are not recommended in metabolic syndrome. However, some recent large studies have shown a better metabolic profile with newer third generation vasodilating beta-blockers, such as Carvedilol and Nebivolol. Vasodilating action of Carvedilol and Nebivolol, due respectively to alpha1-blocking effect and release of nitric oxide, explains the lack of adverse metabolic effects of these beta-blockers that could also be used in hypertensive patients with metabolic syndrome.