Lipid Panel With Apolipoprotein B (ApoB), GlycA (Inflammation), Diabetes Risk Index (DRI)

Serum or plasma, shipped refrigerated

1 mL

0.5 mL (Note: This volume does not allow for repeat testing.)

Plain red-top tube (preferred); NMR LipoTube (black-and- yellow-top tube), lavender-top (EDTA-no gel) tube, or green-top (heparin-no gel) tube is acceptable.

Patient fasting is not required; however, in conditions where triglyceride values provide a priori diagnostic information, such as screening for familial hypercholesterolemia or early onset heart disease, pancreatitis, or confirming hypertriglyceridemia, the patient should be counseled to fast 12 to 14 hours prior to blood draw.

This "Extended Lipid Panel" quantifies the components of a typical lipid panel (TC, HDL-C and TG) along with ApoB by nuclear magnetic resonance (NMR) spectroscopy using the Vantera NMR Clinical Analyzer. Results from the Extended Lipid Panel Assay can be used by physicians to assist in CVD risk assessment. The principal protein component of LDL particles, ApoB, has been shown to be associated with CVD and is also an important CVD risk factor.

GlycA is hypothesized to be a nonspecific measure of global inflammation status. Unlike existing biomarkers of inflammation that are discrete molecular species, such as CRP or inflammatory cytokines, GlycA is a composite biomarker that integrates the protein levels and glycosylation states of several of the most abundant acute- phase proteins in serum. This allows for a more stable measure of systemic inflammation with lower intra-individual variability of GlycA than hsCRP. While guidelines recommend two serial measurements be taken at least two weeks apart when using hsCRP for CV disease risk assessment, only one measurement is necessary for evaluation of a patient's CV risk using the GlycA test.

The Diabetes Risk Index (DRI) is intended for use in adult subjects for the quantitative determination of a risk score in serum or plasma. The DRI score (1-100) may be used as an aid in stratifying the risk of developing type 2 diabetes in individuals with normo-glycemia or prediabetes. The Diabetes Risk Index (DRI) is a nuclear magnetic resonance spectroscopy (NMR)-derived multimarker score (values 1-100) that predicts a patient's risk of developing type 2 diabetes mellitus (T2D) independent of glycemic status. DRI derives its performance from the weighted addition of the Lipoprotein Insulin Resistance Index (LP-IR) scores with simultaneously-measured levels of branched-chain amino acids (BCAA).^1-6

If triglyceride level is >800 mg/dL, LDL cholesterol will not be calculated.

GlycA measurements from EDTA plasma specimens are, on average, 3% to 5% lower than from serum samples. GlycA measurements from NMR LipoTube specimens are, on average, 5% to 6% higher than from serum samples collected in red-top tubes. DRI measurements from plasma specimens are on average 8 points lower than from serum specimens.

GlycA is an indicator for a wide range of disease processes and should not be interpreted without a complete clinical history. Recent medical events resulting in tissue injury, infections, or inflammation, which may cause elevated GlycA levels, should also be considered when interpreting results. Hemolysis may reduce GlycA concentrations more than 10%.

This test was developed and its performance characteristics determined by Labcorp. It has not been cleared or approved by the Food and Drug Administration.

Nuclear magnetic resonance (NMR)

Note: The NMR method for Triglycerides, unlike the routine chemical method, is not affected by endogenous glycerol, which might be found in very rare clinical conditions such as Hyperglycerolemia (glycerol kinase deficiency-GKD), an X-linked genetic disorder. Large quantitative differences in the chemical and NMR method results may be attributable to high blood glycerol.