What lipid tests are available to assess cardiovascular risk?

Available Lipid Tests for Cardiovascular Risk Assessment

The standard fasting lipid profile (total cholesterol, HDL cholesterol, LDL cholesterol, and triglycerides) is the only lipid testing recommended for cardiovascular risk assessment in asymptomatic adults, as measurement of additional lipid parameters provides no proven benefit. 1

Standard Lipid Profile Components

The standard lipid profile includes four key measurements:

1. Total Cholesterol (TC) - Measures all cholesterol in blood
2. High-Density Lipoprotein Cholesterol (HDL-C) - Often called "good cholesterol"
3. Low-Density Lipoprotein Cholesterol (LDL-C) - Often called "bad cholesterol"
4. Triglycerides (TG) - Fat molecules that store energy

Derived Lipid Measurements

From the standard lipid profile, additional calculations can be made at no extra cost:

• Total Cholesterol/HDL Ratio - Provides better risk classification than total cholesterol alone 2
• LDL/HDL Ratio - Useful for risk stratification
• Non-HDL Cholesterol - Calculated by subtracting HDL-C from total cholesterol; represents all atherogenic lipoproteins 3

Advanced Lipid Tests (Not Recommended)

The American College of Cardiology Foundation/American Heart Association explicitly recommends against using these advanced tests for cardiovascular risk assessment 1:

• Apolipoprotein B (ApoB) - Reflects LDL particle numbers
• Apolipoprotein A (ApoA) - Associated with HDL
• Lipoprotein(a) [Lp(a)] - Shows modest association with CHD and stroke
• LDL particle size and density measurements
• Lipoprotein subfractions
• Oxidized lipid measurements

Evidence Against Advanced Lipid Testing

Multiple studies have shown that advanced lipid tests provide little to no additional predictive value:

• The Framingham Heart Study found minimal additional risk information from ApoB or ApoB/A-1 ratio compared to the total/HDL-cholesterol ratio 1
• The EPIC-Norfolk study showed no relative benefit of LDL particle number determinations compared to non-HDL cholesterol 1
• A systematic review found no study reporting incremental predictive value of LDL subfractions beyond traditional risk factors 1

Testing Recommendations

• Who should be tested: Men ≥35 years, women ≥45 years, and younger adults with risk factors 2
• Testing frequency: Every 5 years for normal levels; annually for high-risk patients 2
• Fasting requirements: Fasting samples are recommended for accurate LDL and triglyceride measurements 2

Interpretation and Risk Assessment

Lipid levels should be interpreted in the context of overall cardiovascular risk, considering:

• Age and gender
• Diabetes status
• Blood pressure
• Family history
• Smoking status

Common Pitfalls to Avoid

1. Relying solely on total cholesterol - Measuring both TC and HDL provides better risk assessment 2
2. Single measurements - At least two measurements are necessary for accurate assessment 2
3. Testing in non-fasting state - Can affect triglyceride and calculated LDL values 2
4. Neglecting other risk factors - Lipid levels must be interpreted in context of overall risk 2
5. Overvaluing advanced lipid tests - These provide minimal additional predictive value at higher cost 1

Despite marketing claims for advanced lipid testing, the evidence clearly shows that the standard lipid profile remains the most cost-effective and clinically validated approach for cardiovascular risk assessment in asymptomatic adults.