From the Guidelines
Apolipoprotein A1 (ApoA1) should not be used as a treatment goal due to its limited availability, higher cost, and lack of additional information compared to currently used lipid variables. Apolipoprotein A1 (ApoA1) is the major protein component of high-density lipoprotein (HDL), often called "good cholesterol." It plays a crucial role in reverse cholesterol transport, the process by which excess cholesterol is removed from tissues and transported to the liver for elimination. ApoA1 helps form HDL particles and activates lecithin-cholesterol acyltransferase (LCAT), an enzyme that converts free cholesterol to cholesteryl esters, allowing more cholesterol to be packed into HDL particles. Some key points to consider about ApoA1 include:
- Low levels of ApoA1 are associated with increased risk of cardiovascular disease, while higher levels are generally protective against atherosclerosis 1.
- ApoA1 levels can be estimated based on HDL concentration, with plasma apo A1 of <120 mg/dL for men and <140 mg/dL for women approximately corresponding to what is considered as low for HDL-C 1.
- ApoA1 measurement is sometimes included in advanced lipid testing to better assess cardiovascular risk beyond standard cholesterol panels, particularly in patients with family histories of premature heart disease or those with unusual lipid profiles.
- The apoB:apoA1 ratio is one of the strongest risk markers for cardiovascular disease, but its use as a treatment goal is not yet generally recommended due to the limitations mentioned above 1.
From the Research
Apolipoprotein A1 Overview
- Apolipoprotein A1 (ApoA1) is the principal protein component of high-density lipoprotein (HDL) 2
- ApoA1 levels are associated with cardiovascular risk, with both low and high levels linked to increased mortality risk 2
Relationship to Cardiovascular Disease
- A U-shaped relationship exists between ApoA1 levels and cardiovascular mortality, with individuals in the highest decile of ApoA1 levels demonstrating higher cardiovascular mortality 2
- ApoA1 is a stronger prognostic marker than HDL and LDL cholesterol for cardiovascular disease and mortality in elderly men 3
- The apoB:apoA1 ratio is associated with increased cardiovascular risk, with a high ratio indicating greater risk 4, 5
Dietary and Lifestyle Factors
- Dietary factors such as a low-carbohydrate, high-saturated-fat diet, low fiber intake, and low vitamin and mineral intake are associated with an elevated apoB:apoA1 ratio 4
- A healthy diet sufficient in polyunsaturated fats, vitamins, minerals, and lower excess sugars may favorably alter the apoB:apoA1 ratio 4