Cholesterol is a steroid with a secondary hydroxyl group in the C3 position. It is synthesized in many types of tissue, but particularly in the liver and intestinal wall. Approximately three quarters of cholesterol are newly synthesized and a quarter originates from dietary intake.
Cholesterol is synthesised ubiquitously throughout the body and is an essential component of cell membranes and lipoproteins as well as being a precursor for the synthesis of steroid hormones and bile acids.
Cholesterol is mainly transported in two lipoprotein classes (LDL and HDL), both of which play a contradictory role in the pathogenesis of lipid disorders.
Cholesterol assays are used for screening for atherosclerotic risk and in the diagnosis and treatment of disorders involving elevated cholesterol levels as well as lipid and lipoprotein metabolic disorders.
Nonfasting sample results may be slightly lower than fasting results.
REFERENCE INTERVALS
Recommendations of the NCEP Adult Treatment Panel for the following risk-cutoff thresholds for the US American population
|
Desirable cholesterol level |
<5.2 mmol/L |
< 200 mg/dL |
|
Borderline high cholesterol |
5.2‐6.2 mmol/L |
200‐239 mg/dL |
|
High cholesterol |
≥ 6.2 mmol/L |
≥ 240 mg/dL |
Clinical interpretation according to the recommendations of the European Atherosclerosis Society
|
No Lipid metabolism disorder |
Cholesterol Triglyceride |
< 5.2 mmol/L < 2.3 mmol/L |
< 200 mg/dL < 200 mg/dL |
|
Lipid metabolism disorder if HDL-Cholesterol is < 0.9 mmol/L (< 35 mg/dL) |
Cholesterol |
5.2 – 7.8 mmol/L |
200 – 300 mg/dL |
|
Lipid metabolism disorder |
Cholesterol Triglyceride |
> 7.8 mmol/L > 2.3 mmol/L |
> 300 mg/dL > 200mg/dL |