Calc Function

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    Chief Complaint


    Organ System


    Patent Pending

    LDL Calculated

    Calculates LDL based on total and HDL cholesterol and triglycerides.


    Note: the Friedewald formula is known to be inaccurate at extremely high triglyceride and total cholesterol levels. If there is any question about accuracy of estimated LDL, a direct level should be measured.

    • Remember, triglycerides should only be calculated when fasting.
    • The Friedewald formula, on which this calculator is based, is known to be inaccurate at extremes of triglycerides and total cholesterol (Cordova 2004).


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    Creator Insights


    Patients with elevated cholesterol may have success with diet and exercise, however those with other cardiovascular risk factors may require medication to reduce levels significantly.

    Latest LDL Guidelines (NCEP 2004 Update):

    • “Very” High Risk: Guidelines suggest <70mg/dL may be a reasonable option, but data may suggest there is little incremental benefit to this extreme but with high associated cost
    • High Risk (known CAD, known other atherosclerotic dz, diabetes, etc): <100 mg/dL
    • Moderate Risk (>1 risk factor): <130 mg/dL
    • Lower Risk (0-1 risk factors): <160 mg/dL


    LDL cholesterol = total cholesterol - HDL - (triglycerides / 5)

    Facts & Figures


    LDL level, mg/dL Interpretation
    <100  Optimal
    100-129 Near optimal/above optimal
    130-159  Borderline high
    160-189 High
    ≥190 Very high

    From ATP III Guidelines.


    LDL targets:

    • “Very” high risk: guidelines suggest <70mg/dL may be a reasonable option, but data may suggest there is little incremental benefit to this extreme but with high associated cost.
    • High risk (known CAD, known other atherosclerotic disease, diabetes, etc): <100 mg/dL.
    • Moderate risk (>1 risk factor*): <130 mg/dL.
    • Lower risk (0-1 risk factors): <160 mg/dL.

    From NCEP 2004 Guidelines.


    *Risk factors include diabetes, cigarette smoking, HTN (BP 140/90 mm Hg or on antihypertensive medication), low HDL cholesterol (<40 mg/dL), and family history of premature CAD (CAD in male first-degree relative, or father <55 years, or female first-degree relative or mother <65 years).

    Dr. William Friedewald

    About the Creator

    William Friedewald, MD, is professor of biostatistics and epidemiology at the Columbia University Medical Center. His research focuses on mainly cardiovascular disease though he has begun to research how diabetes can affect traumatic brain injury.

    To view Dr. William Friedewald's publications, visit PubMed

    About the Creator
    Dr. William Friedewald