HDL Cholesterol
Overview
HDL cholesterol measures the cholesterol content carried by high-density lipoprotein particles, which are involved in reverse cholesterol transport from peripheral tissues back to the liver for excretion. HDL particles also have anti-inflammatory, antioxidant, and antithrombotic functions that may protect against atherosclerosis. Low HDL levels are associated with increased cardiovascular risk, while higher levels generally correlate with lower risk, although very high levels can be complex to interpret. Clinically, HDL cholesterol is a key component of lipid panels used to estimate atherosclerotic cardiovascular disease (ASCVD) risk and guide prevention strategies.
Clinical Use Cases
- Estimating ASCVD risk as part of a fasting or non-fasting lipid profile.
- Guiding lipid-lowering and lifestyle interventions in dyslipidemia.
- Monitoring response to lifestyle changes (exercise, diet, smoking cessation).
- Research on lipoprotein metabolism and residual cardiovascular risk.
Specimen Types
- Serum.
- Plasma (heparin or EDTA, method-dependent).
Measurement Methods
- Homogeneous enzymatic colorimetric assays after selective masking of non-HDL lipoproteins.
- Precipitation methods followed by enzymatic cholesterol assay (older, less common).
- Ultracentrifugation with subsequent cholesterol measurement (reference/lab research).
Test Preparation and Influencing Factors
- Can be measured in fasting or non-fasting state; fasting preferred if full lipid panel including triglycerides is needed.
- Smoking, obesity, physical inactivity, and high-carbohydrate diets lower HDL.
- Moderate alcohol intake, regular aerobic exercise, weight loss, and estrogen therapy can increase HDL.
- Acute illness, uncontrolled diabetes, nephrotic syndrome, and some drugs (beta-blockers, anabolic steroids) may reduce HDL levels.
Synonyms
- High-density lipoprotein cholesterol.
- HDL-C.
- “Good” cholesterol (colloquial).