HDL cholesterol and LDL cholesterol have opposite mechanisms of action on cholesterol. LDL is responsible for transporting cholesterol from the liver to the outside of the liver, whereas HDL does the opposite and is responsible for transporting cholesterol from the outside of the liver to the inside of the liver for metabolism.
Lower HDL cholesterol prevents extrahepatic cholesterol from being transported to the liver in a timely manner, resulting in higher cholesterol levels in the blood, which is most common in patients suffering from atherosclerosis, nephrotic syndrome, and diabetes mellitus.
Increased LDL cholesterol is the main cause of hypercholesterolemia, which is positively correlated with the development of coronary heart disease and can be used to determine the risk of coronary heart disease; it can also be seen in patients suffering from nephrotic syndrome, hypothyroidism, hereditary hyperlipoproteinemia, cholestatic jaundice, and obesity.
Low HDL and high LDL suggest that the patient has abnormal lipid metabolism, and it is recommended that the patient be evaluated in a regular hospital to avoid delays.