Metabolic syndrome is defined in the 2007 China Adult Dyslipidemia Guidelines as follows: Metabolic syndrome can be diagnosed if the following 3 items are met. 1. Abdominal obesity: waist circumference >90cm in men and >85cm in women. 2. TG ≥1.7mmol/L. 3. HDL-C <1.04mmol/L. 4. Blood pressure ≥130/85mmHg. 5. Fasting blood glucose ≥6.1mmol/L, 2 hours postprandial blood glucose ≥7.8mmol/L or history of diabetes mellitus. The pathological basis of metabolic syndrome In 1988, Reaven found that obesity, type 2 diabetes, abnormal lipid metabolism, hypertension, hyperinsulinemia and coronary heart disease often occurred in the same patient, and called this phenomenon "X syndrome". 1999, the World Health Organization named this series of clinical manifestations as In 1999, the World Health Organization named this series of clinical manifestations as "metabolic syndrome". Since then, many international organizations have discussed metabolic syndrome, but the definition of metabolic syndrome varies, and there is even a debate on whether the phenomenon exists. The metabolic syndrome is a group of clinical manifestations based on insulin resistance as the pathophysiological basis and includes multiple risk factors, including central obesity, elevated blood pressure, abnormal glucose and lipid metabolism, hyperinsulinemia, procoagulant state, increased urinary protein excretion, endothelial dysfunction, hyperuricemia, and increased levels of inflammatory markers. Clinical manifestations of metabolic syndrome After looking at the definition of metabolic syndrome in domestic and international guidelines, it is easy to find that the core clinical manifestations of metabolic syndrome are "three highs and one abnormality", namely high body weight, high blood pressure, high blood sugar and abnormal lipid metabolism. Various guidelines agree that the metabolic syndrome can manifest as abnormal blood pressure and glucose and lipid metabolism, and there is substantial evidence that the metabolic syndrome is associated with cardiovascular disease incidence and mortality. Metabolic syndrome is not a unique disease since it is a syndrome, and there is no need to argue about its existence or non-existence; it can be diagnosed as long as the clinical manifestations meet the common features mentioned above. Other clinical manifestations of metabolic syndrome include homocysteinemia, elevated blood uric acid, procoagulant state, abnormal alpha lipoprotein, fibrinogen and fibrinogen activator inhibitor-1 levels. Patients with metabolic syndrome are actually high-risk patients with multiple risk factors for cardiovascular disease.