1. What is the Friedewald Equation?

The Friedewald equation is a formula used to estimate LDL cholesterol levels from measurements of total cholesterol, HDL cholesterol, and triglycerides. It provides a cost-effective alternative to direct LDL measurement when fasting samples are available.

2. How Does the Calculator Work?

The calculator uses the Friedewald equation:

Where:

• Total Cholesterol — Measured in mg/dL
• HDL — High-density lipoprotein cholesterol in mg/dL
• Triglycerides — Measured in mg/dL

Explanation: The equation estimates LDL cholesterol by subtracting HDL and VLDL (estimated as triglycerides/5) from total cholesterol.

3. Importance of LDL Calculation

Details: LDL cholesterol is a major risk factor for cardiovascular disease. Accurate estimation helps in assessing cardiovascular risk and guiding treatment decisions for cholesterol management.

4. Using the Calculator

Tips: Enter total cholesterol, HDL, and triglycerides in mg/dL. All values must be valid (greater than 0). Note that this calculation requires fasting triglyceride levels for accuracy.

5. Frequently Asked Questions (FAQ)

Q1: When is the Friedewald equation not accurate?
A: The equation is less accurate when triglyceride levels are above 400 mg/dL, in non-fasting samples, or in certain medical conditions.

Q2: What are optimal LDL levels?
A: Optimal LDL is generally below 100 mg/dL, though targets may vary based on individual cardiovascular risk factors.

Q3: Why divide triglycerides by 5?
A: This approximates the VLDL cholesterol level, as VLDL carries most triglycerides in the blood.

Q4: Are there alternative methods for LDL calculation?
A: Yes, direct LDL measurement or the Martin/Hopkins method may be used when triglycerides are elevated.

Q5: Should this be used for clinical decision making?
A: While useful for screening, clinical decisions should be based on comprehensive lipid profile and individual risk assessment.