Apolipoprotein A1, Serum
Use
Apolipoprotein A1 (ApoA1) plays a central role in reverse cholesterol transport and is the main protein component of high-density lipoprotein (HDL). There is a strong inverse relationship between ApoA1 concentrations and the risk for coronary artery disease. Elevated ApoA1 levels are associated with a reduced risk of myocardial infarction compared to HDL-C concentrations alone. In statin-treated patients, increased ApoA1 concentration correlates with lower cardiovascular event risks, making it useful for evaluating cardiovascular disease risk and detecting Tangier disease, where levels below 25 mg/dL are indicative of genetic disorder.
Special Instructions
If not ordering electronically, complete, print, and send a Cardiovascular Test Request Form (T724) with the specimen.
Limitations
Apolipoprotein A1 is not a 1:1 surrogate for HDL particles due to variability in protein-per-particle ratios and cholesterol content. This heterogeneity may affect the clinical interpretation of ApoA1 in comparison to HDL-C. Also, results can be affected by the presence of gross hemolysis or icterus in specimens, which are reasons for rejection.
FDA ApprovedNew York Approved
Methodology
Immunoassay (Turbidimetric)
Biomarkers
LOINC Codes
- 1869-7
- 1869-7
Result Turnaround Time
1-2 days
Related Documents
For more information, please review the documents below
Specimen
Serum
Volume
0.5 mL
Minimum Volume
0.5 mL
Container
Serum gel (preferred) or red top
Collection Instructions
Centrifuge and aliquot within 2 hours of collection. Red-top tubes should be centrifuged and aliquoted within 2 hours.
Causes for Rejection
Gross hemolysis, gross icterus
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | 24 hours |
| Refrigerated | 8 days |
| Frozen | 60 days |