Metabolic syndrome represents a cluster of clinical, biochemical and humoral abnormalities associated with impaired insulin action in glucose metabolism. In the literature also the term syndrome of insulin resistance, dysmetabolic syndrome X, Reaven syndrome or Kaplans´dead quartet can be found. Hyperinsulinaemia, central obesity, essential hypertension, dyslipidaemia, impaired glucose homeostasis or type 2 diabetes, hyperuricaemia, hypercoagulable state, endothelial dysfunction and increased markers of inflammation such as C-reactive protein, selectines, adhesion molecules, pro-inflammatory cytokines are the typical components of metabolic syndrome increasing the risk of cardiovascular complications. List of currently recognized clinical and biochemical manifestations continues to expand and include also non-alcoholic steatohepatitis, polycystic ovaric syndrome (PCOS), hyperhomocysteinaemia and others. No standard definition of metabolic syndrome has been routinely used. The WHO initially proposed a definition of metabolic syndrome in 1998, and more recently NCEP-ATP III provided a new working definition in 2001, which is more suitable for clinical practice. Prevalence of metabolic syndrome is very high, about 25- 30 % in Caucasians, depending on diagnostic criteria used. The clinical significance of metabolic syndrome is augmented by its association with increased and accelerated atherosclerosis. Whether IR predicts cardiovascular disease (CVD) independently of diabetes and other CVD risk factors is still a matter of controversy. Recently there is a growing evidence that metabolic syndrome increases also the risk of all-cause mortality and risk of certain tumors.

        Key words: Insulin resistance - Insulin - Dyslipidaemia - Diabetes mellitus - Essential hypertension