This Cholesterol Blood test is used to screen for risk of developing heart disease. Adults should have a total blood test for cholesterol once every five years or more frequently if you are being treated for high cholesterol. High levels of cholesterol that reflect high levels of HPLs may be caused by and inherited defect in lipoprotein metabolism, by disease of the endocrine system, by liver disease, or by renal disease. Low levels of cholesterol in the plasma may reflect an inherited deficiency of either LDL or HDL, or they may reflect impairment of liver function. Various hormone conditions are also related to cholesterol levels. Low cholesterols are found in cases of hyperthyroidism, severe liver disease, pernicious anemia, and with increased estrogens. Pregnancy is accompanied by a moderate increase. Cholesterol is increased in early hepatitis, obstructed bile ducts, primary biliary cirrhosis, nephrotic syndrome, and diabetic meningitis. Finally, it appears that cholesterol is implicated in atherosclerosis and heart disease. Evaluate risk of coronary arterial occlusion, atherosclerosis, myocardial infarction, and complications including the demise of the patient.