Test Catalog

Test ID: LDLD    
Low-Density Lipoprotein (LDL) Cholesterol, Beta-Quantification, Serum

Useful For Suggests clinical disorders or settings where the test may be helpful

Evaluation of cardiovascular risk


Verification of estimated low-density lipoprotein cholesterol (LDL-C) in patients with hypertriglyceridemia or extremely low LDL-C


Diagnosis of familial hypobetalipoproteinemia and abetalipoproteinemia

Clinical Information Discusses physiology, pathophysiology, and general clinical aspects, as they relate to a laboratory test

Low-density lipoprotein cholesterol (LDL-C) is acknowledged as being causally related with atherosclerotic cardiovascular disease. LDL-C remains the primary focus for cardiovascular risk assessment and effectiveness of risk reduction interventions including diet, physical activity and pharmacologic therapies.


Low-density lipoproteins are a heterogeneous population of lipid particles classically defined as having a density of 1.006 to 1.063 kg/L obtained by preparative ultracentrifugation. The gold standard beta-quantification (beta-quant or BQ) method combines ultracentrifugation with precipitation and yields a direct quantitative measurement of LDL-C, intermediate-density lipoprotein cholesterol, and lipoprotein(a) cholesterol.


Extremely low concentrations of LDL-C are associated with abetalipoproteinemia and hypobetalipoproteinemia. In both cases, individuals will have very low total cholesterol and diminished or absent LDL-C, apolipoprotein B, and very low-density lipoprotein cholesterol. Patients may exhibit clinical signs and symptoms of polyneuropathy, intestinal fat malabsorption, hepatosteatosis, and fat soluble vitamin deficiencies.

Reference Values Describes reference intervals and additional information for interpretation of test results. May include intervals based on age and sex when appropriate. Intervals are Mayo-derived, unless otherwise designated. If an interpretive report is provided, the reference value field will state this.

The National Lipid Association and the National Cholesterol Education Program (NCEP) have set the following guidelines for LDL-C in adults (ages 18 years and up):

Desirable: <100 mg/dL

Above desirable: 100-129 mg/dL

Borderline high: 130-159 mg/dL

High: 160-189 mg/dL

Very high: > or =190 mg/dL


The Expert Panel on Integrated Guidelines for Cardiovascular Health and Risk Reduction in Children and Adolescents has set the following guidelines for LDL-C in children and adolescents (ages 2-17 years):

Acceptable: <110 mg/dL

Borderline high: 110-129 mg/dL

High: > or =130 mg/dL

Interpretation Provides information to assist in interpretation of the test results

Mayo Clinic has adopted the National Lipid Association classifications, which are included as reference values on Mayo Clinic and Mayo Clinic Laboratories reports (see Reference Values). Lipids are most commonly measured to assess cardiovascular risk. Maintaining desirable concentrations of lipids lowers the risk of heart attacks or strokes.


Establishing appropriate treatment strategies and lipid goals requires consideration of low-density lipoprotein cholesterol (LDL-C) in context with other risk factors including: age, sex, smoking status, family and personal history of heart disease. All guidelines recommend aggressive lipid lowering for patients with LDL cholesterol above 190 mg/dL.


Values below 20 mg/dL in untreated patients may be consistent with hypobetalipoproteinemia. Complications due to fat malabsorption may be present in affected individuals.


Undetectable LDL-C is highly suggestive of abetalipoproteinemia. Related polyneuropathy may exist in affected individuals.

Cautions Discusses conditions that may cause diagnostic confusion, including improper specimen collection and handling, inappropriate test selection, and interfering substances

Result can be falsely decreased in patients with elevated levels of N-acetyl-p-benzoquinone imine (NAPQI)-a metabolite of acetaminophen), N-acetylcysteine (NAC), and metamizole.

Clinical Reference Recommendations for in-depth reading of a clinical nature

1. Expert Panel on Detection, Evaluation, and Treatment of High Blood Cholesterol in Adults: Executive Summary of the Third Report of the National Cholesterol Education Program (NCEP) Expert Panel on Detection, Evaluation, and Treatment of High Blood Cholesterol in Adults (Adult Treatment Panel III). JAMA. 2001 May 16;285(19):2486-2497

2. Jacobson TA, Ito MK, Maki KC, et al: National Lipid Association recommendations for patient-centered management of dyslipidemia: part 1 - executive summary. J Clin Lipidol. 2014 Sep-Oct;8(5):473-488

3. Expert panel on integrated guidelines for cardiovascular health and risk reduction in children and adolescents: summary report. Pediatrics. 2011 Dec;128(Suppl 5):S213-S256

4. Grundy SM, Stone NJ, Bailey AL, et al: 2018 AHA/ACC/AACVPR/AAPA/ABC/ACPM/ADA/AGS/APhA/ASPC/NLA/PCNA Guideline on the Management of Blood Cholesterol: Executive Summary: A Report of the American College of Cardiology/American Heart Association Task Force on Clinical Practice Guidelines. Circulation. 2019 Jun 18;139(25):e1046-e1081. doi: 10.1161/CIR.0000000000000624