Lipid TestsComparison of LDL Particle Count With Other Available Lipid Tests

Despite the wide availability of advanced lipoprotein tests, no reference standard exists for Low Density Lipoprotein Cholesterol (LDL-C) due to inherent problems with each of the assays. Newer methods for estimating LDL particle numbers, including nuclear magnetic resonance (NMR) spectroscopy and vertical auto profile (VAP) are currently under investigation. NMR has been proposed as having the best correlation with adverse cardiovascular outcomes. Unfortunately, the accuracy of LDL-C or LDL particle number measurements is currently not monitored by national standardization programs. Direct comparisons between the various testing methods have been limited restricting our ability to accurately interpret and compare values across vendors and lipid parameters.

Our hypothesis is that:

1. LDL particle count numbers, as determined by NMR (Liposcience), provides the best estimates of cardiovascular risk.
2. Discrepancies exist between the LDL particle count by NMR and other values as presented by calculated LDLC and directly measured LDL (VAP and ion mobility).

The investigators will enroll 100 patients recruited from the Lipid Clinic at the Scripps Center for Integrative Medicine. Each patient will have one blood draw from which four tests will be analyzed. Risks are associated with drawing blood, which will be minimized by using Scripps Clinic Lab technicians. The potential loss of personal health information will be reduced by limiting access to study and lab staff and keeping information password-protected on Scripps servers.