Total Cholesterol
Test Description
Cholesterol is synthesized in the liver from dietary fats. Its functions include being
used in the production of bile salts and several of the steroid hormones, and as a
part of cell membranes. Cholesterol is transported in the blood by the low density
lipoproteins (LDLs, or “bad” cholesterol) and high density lipoproteins (HDLs, or
“good” cholesterol). A great deal of research has focused on the role of cholesterol
in heart disease. High levels of cholesterol in the blood (hypercholesterolemia),
especially in combination with low levels of HDL, have been found to increase the
person’s risk of atherosclerosis and heart disease. This test allows evaluation of this
risk potential, assists in determining treatment options, and is used to monitor
effectiveness of treatment.
• In all adults aged 20 years or older, a fasting lipoprotein profile (total cholesterol, LDL cholesterol,
HDL cholesterol, and triglycerides) should be obtained once every 5 years. If the
testing opportunity is nonfasting, only the values for total cholesterol and HDL cholesterol
will be usable. In such a case, if total cholesterol is ≥200 mg/dL or HDL is <40 mg/dL, a
follow-up lipoprotein profile is needed for appropriate management based on LDL.
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Normal Values : Desirable <200 mg/dL (<5.18 mmol/L SI units)
Abnormal Values
Borderline High: 200–239 mg/dL (5.18–6.19 mmol/L SI units)
High: >239 mg/dL (>6.20 mmol/L SI units)
Possible Meanings of Abnormal Values
Increased Decreased
Atherosclerosis AIDS
Biliary cirrhosis Chronic anemia
Cardiovascular disease Hemolytic anemia
Hypercholesterolemia Hyperthyroidism
Hyperlipidemia Hypolipoproteinemia
Hypertriglyceridemia Liver disease
Hypothyroidism Malabsorption
Liver disease/biliary obstruction Malnutrition
Nephrotic syndrome Pernicious anemia
Obesity Sepsis
Pancreatic dysfunction Severe infections
Preeclampsia Stress
Pregnancy
Uncontrolled diabetes mellitus
Xanthomatosis
Contributing Factors to Abnormal Values
• Drugs which may increase cholesterol levels: atypical antipsychotics, beta-blockers,
corticosteroids, disulfiram, lansoprazole, levodopa, lithium, oral contraceptives,
pergolide, phenobarbital, phenytoin, sulfonamides, testosterone, thiazide diuretics,
ticlopidine, venlafaxine.
• Drugs which may decrease cholesterol levels: ACE-inhibitors, allopurinol, androgens,
cholesterol lowering agents, erythromycin, estrogens, filgrastim, levothyroxine,
metformin, phenytoin, prazosin, tamoxifen, terazosin.
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Interventions/Implications
Pretest
• Explain to the patient the purpose of the test and the need for a blood sample to be
drawn.
• Fasting for 12 hours is required prior to the test. Water is permitted.
• No alcohol is allowed for 24 hours prior to the test.
Procedure
• A 7-mL blood sample is drawn in a red-top collection tube.
• Gloves are worn throughout the procedure.
Posttest
• Apply pressure at venipuncture site. Apply dressing, periodically assessing for continued
bleeding.
• Label the specimen and transport it to the laboratory.
• Report abnormal findings to the primary care provider.
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Clinical Alerts
• If the test result is >200 mg/dL, patient education is needed regarding:
• reduced intake of saturated fat and cholesterol
• increased physical activity
• weight control
• Depending on levels of other lipoproteins and the degree of hypercholesterolemia
present, cholesterol-lowering medication may be initiated, along with lifestyle
modifications.
Cholinesterase.
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