1. What is the Sampson Equation?

The Sampson equation is a novel method for calculating LDL cholesterol (LDL-C) from total cholesterol (TC), HDL cholesterol (HDL-C), and triglycerides (TG). It provides a more accurate estimation of LDL-C compared to the traditional Friedewald formula, especially in patients with high triglyceride levels or low LDL-C values.

2. How Does the Calculator Work?

The calculator uses the Sampson equation:

Where:

• \( TC \) — Total cholesterol (mg/dL)
• \( HDL-C \) — HDL cholesterol (mg/dL)
• \( TG \) — Triglycerides (mg/dL)

Explanation: The equation uses multiple regression coefficients to provide a more accurate estimation of LDL cholesterol without requiring direct measurement.

3. Importance of LDL-C Calculation

Details: Accurate LDL cholesterol estimation is crucial for cardiovascular risk assessment, treatment decisions, and monitoring the effectiveness of lipid-lowering therapies.

4. Using the Calculator

Tips: Enter total cholesterol, HDL cholesterol, and triglycerides in mg/dL. All values must be valid (greater than 0). For optimal accuracy, use fasting lipid panel results.

5. Frequently Asked Questions (FAQ)

Q1: Why use Sampson equation instead of Friedewald formula?
A: The Sampson equation provides more accurate LDL-C estimation, especially in patients with high triglyceride levels (>400 mg/dL) or very low LDL-C levels.

Q2: What are normal LDL-C values?
A: Optimal LDL-C is <100 mg/dL, near optimal is 100-129 mg/dL, borderline high is 130-159 mg/dL, high is 160-189 mg/dL, and very high is ≥190 mg/dL.

Q3: When should lipid measurements be taken?
A: Fasting samples (9-12 hours) are preferred for accurate triglyceride measurement, though non-fasting samples can be used for total and HDL cholesterol.

Q4: Are there limitations to this equation?
A: While more accurate than Friedewald, the Sampson equation may still have limitations in certain populations such as those with dysbetalipoproteinemia or extremely high triglyceride levels.

Q5: Should this replace direct LDL measurement?
A: For most clinical purposes, calculated LDL is sufficient. Direct measurement may be needed in specific cases such as hypertriglyceridemia or when calculated values are inconsistent with clinical findings.