/LDL Cholesterol (Friedewald)

LDL Cholesterol (Friedewald)

Calculates LDL from standard lipid panel

Total Cholesterol
mg/dL
HDL Cholesterol
mg/dL
Triglycerides
mg/dL

Total Score

0

Optimal LDL level.

0–99+Low
100–129+Moderate
130–159+Moderate
160–189+High
190–999+High

Disclaimer: The clinical scoring and algorithms on this platform are intended strictly for professional informational purposes. They do not constitute a definitive medical diagnosis, treatment, or clinical decision. The final judgment and responsibility lie with the treating physician.

Yasal Uyarı: Bu platformdaki klinik skorlamalar ve algoritmalar yalnızca sağlık profesyonellerini bilgilendirme amaçlıdır. Herhangi bir kesin tıbbi teşhis, tedavi veya klinik karar yerine geçemez. Nihai karar ve sorumluluk hastayı yatak başında değerlendiren hekime aittir.

Clinical Overview

Directly measuring Low-Density Lipoprotein (LDL) cholesterol requires specialized and expensive ultracentrifugation techniques. The Friedewald equation offers a highly practical and cost-effective workaround by estimating LDL from a standard lipid panel: Total Cholesterol, High-Density Lipoprotein (HDL), and Triglycerides. It has been the cornerstone of cardiovascular risk assessment for decades.

Clinical Pearl

The formula implicitly assumes a fixed ratio of triglycerides to Very-Low-Density Lipoprotein (VLDL) cholesterol. Because chylomicrons post-prandially distort this ratio, standard Friedewald calculations technically demand a strict 9-12 hour fasting lipid panel.

Pitfalls & Warnings

  • Completely mathematically invalid if Triglycerides are > 400 mg/dL. In such cases, the Martin-Hopkins equation or direct LDL measurement is absolutely required.
  • Tends to underestimate LDL when LDL is naturally very low (< 70 mg/dL), potentially providing false reassurance to high-risk cardiovascular patients.

Academic References

Friedewald WT, Levy RI, Fredrickson DS. Estimation of the concentration of low-density lipoprotein cholesterol in plasma, without use of the preparative ultracentrifuge. Clin Chem. 1972;18(6):499-502.

Disclaimer: The clinical scoring and algorithms on this platform are intended strictly for professional informational purposes. They do not constitute a definitive medical diagnosis, treatment, or clinical decision. The final judgment and responsibility lie with the treating physician.