Test Details
LDL Particle Number (LDL-P)
LDL-P is a measurement of the number of LDL particles in serum as opposed to LDL-C which is the measurement of the amount of cholesterol inside the LDL particle.
Methodology
600 MHz nuclear magnetic resonance (NMR)
Patient Preparation
8-12 hour fast prior to collection. Patient may drink water, black coffee or tea (no milk, cream or sugar).
Preferred Specimen
2.0 mL serum (1.0 mL minimum) collected in red/yellow top serum separator tube (Z-Top tube)
Alternate Specimen
2.0 mL serum (1.0 mL minimum) collected in black/yellow top serum separator tube (Z-Top tube)
Transport Temperature
Refrigerated (ship on frozen cold packs)
Stability
Refrigerated: 12 days
Lab Values
LDL Particle Number (LDL-P)
- Optimal: <1200 nmol/L
- Borderline: 1200-1800 nmol/L
- Increased Risk: >1800 nmol/L
Clinical Significance
LDL Particle Number (LDL-P)
An alternative measure of LDL quantity is LDL particle number (LDL-P), determined directly by nuclear magnetic resonance (NMR) spectroscopy. Data from multiple epidemiological studies have demonstrated that LDL-P better predicts cardiovascular events than LDL-C concentrations, particularly in patients whose LDL-P and LDL-C levels are discordant.1
References:
- Cole TG, Contois JH, Csako G, et al. Association of apolipoprotein B and nuclear magnetic resonance spectroscopy-derived LDL particle number with outcomes in 25 clinical studies: assessment by the AACC Lipoprotein and Vascular Diseases Division Working Group on Best Practices. Clin Chem. 2013;59(5):752-770.
Treatment Options
LDL Particle Number (LDL-P)
- Lifestyle Modification
- Statins
- Niacin
- Fibrates
- Cholesterol absorption inhibitors (ezetimibe)
- Bile acid sequestrants