(1) Secondary hyperlipidemia refers to dyslipidemia caused by systemic diseases. Systemic diseases that can cause hyperlipidemia mainly include diabetes, nephrotic syndrome and hypothyroidism. Other diseases include renal failure, liver disease, systemic lupus erythematosus, glycogen storage disease, myeloma, lipodystrophy, acute porphyria and polycystic ovary syndrome. In addition, some drugs such as diuretics, beta blockers, glucocorticoids, etc. It may also cause secondary hyperlipidemia.

(2) Primary hyperlipidemia can be diagnosed after excluding secondary hyperlipidemia. It is known that some primary hyperlipidemia is caused by congenital genetic defects, while the causes of other primary hyperlipidemia are not clear.

Step 2 classify

(1) Classification of hyperlipoproteinemia The World Health Organization (WHO) has formulated the classification of hyperlipoproteinemia, which divides * * into six types: I, II A, II B, III, IV and V. This classification method is very helpful to guide the clinical diagnosis and treatment of hyperlipidemia, but it also has some shortcomings, the most obvious of which is too complicated.

(2) Clinical classification From a practical point of view, dyslipidemia can be simply classified. There are mainly hypercholesterolemia with elevated serum cholesterol, hypertriglyceridemia with elevated serum triglycerides, and mixed hyperlipidemia with elevated serum cholesterol and triglycerides. In addition, there is low high density lipoprotein hyperlipidemia with low serum high density lipoprotein cholesterol level.

(3) Genotyping With the rapid development of molecular biology, people's understanding of hyperlipidemia has gradually deepened to the gene level. It has been found that a considerable number of patients with hyperlipidemia have single or multiple gene defects. Hyperlipidemia caused by gene defect is usually called familial hyperlipidemia because of its family accumulation and obvious genetic tendency.