High Density Lipoprotein Cholesterol
Cholesterol circulates in blood bound to lipoproteins; the two
main ones being low density lipoprotein (LDL) and high density
lipoprotein (HDL). HDL concentrations are inversely correlated
with risk of athersclerosis, that is, high levels are beneficial.
Modest increases in total cholesterol may be due to increased HDL
cholesterol so it is important that HDL is measured before any
treatment is initiated.
Part of Profile
Request on ICE
If HDL cholesterol is requested as part of a lipid profile then
patient must fast for 10 hours prior to blood collection (for
follow up tests diabetic patients may not need to fast). Patients
do not need to fast if only HDL cholesterol is requested.
Causes for Rejection
Unlabelled or incorrectly labelled sample
The concept of a reference range is flawed and acceptable levels
depend on presence of other coronary risk factors. Ideally levels
should be >0.9 mmol/L. For primary prevention use risk tables
which incorporate a total:HDL cholesterol ratio.
Low HDL levels may be associated with obesity, type 2 diabetes
and physical inactivity.