ABSTRACT

It has been accurately observed that certain risk factors in humans appear to ‘cluster’ with clinical states such as obesity and type 2 diabetes. Specifically, this risk factor clustering, and the association with insulin resistance, led investigators to propose the existence of a unique pathophysiological condition1. Many names have been provided to describe this clinical state including ‘metabolic syndrome’, ‘syndrome X’, and ‘insulin resistance syndrome’1. The particular names that refer to this risk factor clustering describe the human condition characterized by the presence of co-existing traditional risk factors for cardiovascular disease (CVD), such as hypertension, dyslipidemia, glucose intolerance, obesity, and insulin resistance, in addition to non-traditional CVD risk factors, such as inflammatory processes and abnormalities of the blood coagulation system2-6. Table 1.1 lists conditions and components associated with the clustering of risk factors. As seen, the components that are associated with risk factor clustering, e.g. ‘metabolic syndrome’, include not only many of the traditional risk factors, e.g. lipids, obesity, hypertension, but also components that represent aspects of vascular health, such as endothelial dysfunction, inflammation, and parameters assessing blood coagulability7. Recently, a joint statement released by the American Diabetes Association (ADA) suggested that, as a construct that denoted risk factor clustering, ‘metabolic syndrome’ has been a useful paradigm in that it draws attention to the fact that risk factors tend to cluster in patients1. However, the ADA felt that, while there is no doubt that certain CVD risk factors cluster, it was their impression that metabolic syndrome has

been imprecisely defined1. For purpose of this Atlas, we will refer to the clustering of CVD risk factors as indicative of a state of increased cardiometabolic risk.