Cholesterol (Total)

Overview

Total cholesterol measures the sum of low-density lipoprotein (LDL),
high-density lipoprotein (HDL), and very low-density lipoprotein (VLDL)
cholesterol in blood. It serves as a key indicator of lipid metabolism and
cardiovascular risk. Elevated levels indicate dyslipidemia and increased
atherosclerosis risk, while low levels may occur in malnutrition,
hyperthyroidism, or liver disease. It is clinically useful for cardiovascular
disease risk assessment and guiding statin therapy decisions.

Clinical Use Cases

  • Cardiovascular risk stratification in primary prevention.
  • Diagnosis of familial hypercholesterolemia.
  • Monitoring response to lipid-lowering therapy.
  • Assessing dyslipidemia in metabolic syndrome.

Specimen Types

  • Serum.
  • Plasma (EDTA, heparin).
  • Whole blood (point-of-care).

Measurement Methods

  • Enzymatic cholesterol esterase and cholesterol oxidase (CHOD-PAP).
  • Direct homogeneous assays.
  • Ultracentrifugation (reference method).

Test Preparation and Influencing Factors

  • Fasting 9-12 hours recommended for accuracy with triglycerides >150
    mg/dL.
  • Recent meals elevate non-fasting levels.
  • Medications (steroids, beta-blockers, estrogens) may increase levels.
  • Physiological factors: age, pregnancy, hypothyroidism elevate; liver disease
    lowers.

Synonyms

  • Total serum cholesterol.
  • TC.
  • Serum cholesterol.

Further Reading

  • Cholesterol Test; Mayo Clinic;
  • Cholesterol – StatPearls; NCBI Bookshelf;
  • Cholesterol Levels: MedlinePlus Medical Test; MedlinePlus;