While upholding the central importance of the Low Density Lipoprotein cholesterol (LDLC) fraction, they extend the focus to the important role of the LDL protein component, apolipoprotein B (“apoB”), to an additional cholesterol fraction: the triglyceride (“TG”, fat) -associated cholesterol (remnant particles, “Remnant-C”) and to Lipoprotein(a) (“Lp(a)”).
This expanded view was motivated by the impact of new effective treatments that drastically lower LDLC and by the increased prevalence of diabetes and metabolic syndrome. It translates into the consensus-based recommendations transliterated in this glossary table:
- Follow-up of lipid profiles of a patient, from baseline at diagnosis to on-treatment measurements, should be ideally performed with the same assay method (and preferably the same laboratory and instrument).
- Laboratories..should report lipid profiles with declaration of the assay method/manufacturer used.
- Values near the treatment decision cutoffs should be confirmed by ≥ 2 repeated measurements by the same method and then averaged.
- Comprehensive assay(s) of atherogenic lipoproteins should not only assess the risk conferred by LDL particles, but also by remnant particles, and Lp(a).
- When LDLC is unavailable because of an invalid Friedewald equation (TG ≥ 400 mg/dL), calculation of non-High Density Lipoprotein Cholesterol (non-HDLC) should be used instead of direct LDLC. Non-HDLC can be calculated in the fasting and non-fasting state, independent of TG variability and also includes an estimate of Remnant-C.
- LDLC continues to be the primary target of lipid-lowering therapy. But, when LDLC goal is achieved, then non-HDLC or apoB should be preferred as secondary treatment targets in patients with triglycerides (TG) ≥ 175 mg/dL, obesity, metabolic syndrome, or type 2 diabetes.
- The ApoB assay can estimate LDLP (95% of apoB) plus Remnant-P and Lp(a) particle numbers in the fasting and non-fasting state.
- The Lp(a)-corrected LDLC should be assessed at least once if the patient shows a poor response to LDL-lowering therapy or in patients with suspected or known high Lp(a).
(1) Langlois, M. R. and 21 other authors. Quantifying Atherogenic Lipoproteins: Current and Future Challenges in the Era of Personalized Medicine and Very Low Concentrations of LDL Cholesterol. A Consensus Statement from EAS and EFLM. Clinical Chemistry 64, 1006–1033 (2018).
(2) European Atherosclerosis Society (EAS) and the European Federation of Clinical Chemistry and Laboratory Medicine (EFLM) Joint Consensus Initiative
