Cholesterol, HDL, Serum
Clinical Information Discusses physiology, pathophysiology, and general clinical aspects, as they relate to a laboratory test
High density lipoprotein (HDL) is the smallest of the lipoprotein particles and comprises a complex family of lipoprotein particles that exist in a constant state of dynamic flux as the particles interact
with other HDL particles and with low density lipoprotein (LDL) particles and very low density lipoprotein (VLDL) particles. HDL has the largest proportion of protein relative to lipid compared to
other lipoproteins (>50% protein).
Total cholesterol levels have long been known to be related to coronary heart disease (CHD). HDL cholesterol is also an important tool used to assess an individual's risk of developing CHD since a strong negative relationship between HDL cholesterol concentration and the incidence of CHD has been reported.
In some individuals, exercise increases the HDL cholesterol level; those with more physical activity have higher HDL cholesterol values.
Cardiovascular risk assessment
Values >60 mg/dL are considered a negative risk factor for coronary heart disease (CHD) and are considered protective. Values > or = 80 to 100 mg/dL may indicate metabolic response to certain medications such as hormone replacement therapy, chronic liver disease, or some form of chronic intoxication, such as with alcohol, heavy metals, industrial chemicals including pesticides.
Values <40 mg/dL correlate with increased risk for CHD.
High density lipoprotein values < or = 5 mg/dL occur in Tangier disease, in association with cholestatic liver disease, and in association with diminished hepatocyte function.
See Lipids and Lipoproteins in Blood Plasma (Serum) in Special Instructions.
Cautions Discusses conditions that may cause diagnostic confusion, including improper specimen collection and handling, inappropriate test selection, and interfering substances
Fasting is not necessary but is preferable. However, if the high density lipoprotein cholesterol data is used to calculate the low density lipoprotein cholesterol, fasting is required since triglycerides concentration is used in the calculation.
Reference Values Describes reference intervals and additional information for interpretation of test results. May include intervals based on age and sex when appropriate. Intervals are Mayo-derived, unless otherwise designated. If an interpretive report is provided, the reference value field will state this.
The National Cholesterol Education Program (NCEP) has set the following guidelines for lipids (total cholesterol, triglycerides, high density lipoprotein [HDL], and low density lipoprotein [LDL] cholesterol) in adults ages 18 and up:
Low (removed HDL): <40 mg/dL
Normal: 40-60 mg/dL
High: >60 mg/dL
The National Cholesterol Education Program (NCEP) and National Health and Nutrition Examination Survey (NHANES) has set the following guidelines for lipids (total cholesterol, triglycerides, HDL, and LDL cholesterol) in children ages 2-17:
Low HDL: <40 mg/dL
Borderline low: 40-59 mg/dL
Normal: > or =60 mg/dL
Also see age and sex adjusted reference values in Cholesterol, HDL-Percentile Ranking in Lipids and Lipoproteins in Blood Plasma (Serum) in Special Instructions.
Clinical References Provides recommendations for further in-depth reading of a clinical nature
1. Tietz Textbook of Clinical Chemistry. Edited by CA Burtis, ER Ashwood. Philadelphia, WB Saunders Company, 1994
2. Rifai N, Warnick GR: Laboratory Measurement of Lipids, Lipoproteins, and Apolipoproteins. AACC Press, Washington DC, 1994