Small LDL particles – the true risk factor!

Worldwide, coronary artery disease is one of the leading causes of premature death. Early detection of the disease is vital for improving mortality outcomes (and unburden the health care systems as well). In principle, we all agree that hyperlipidaemia is one of the major risk factors, but it seems that we’ve not been looking at the blood lipid profiles close enough. There are, namely, huge numbers of patients with severe coronary artery disease whose blood lipid profiles are fairly normal.
There are two main types of “cholesterols” (LDL and HDL), but both of them are subdivided to many different classes and types. With HDL, it’s not very complicated: HDL should be high, with LDL things get a little messy. High LDL is thought to be the dangerous marker, but the discoveries in the recent years show that sometimes it’s not so and even worse: sometimes total LDL can remain in the normal range, but despite that causing coronary artery disease. Why is that so? LDL comes in two basic types: large, fluffy particles and small, dense particles. The former is believed to be protective, however little doubt remains about the danger of the latter. Small LDL particles are prone to oxidation and are highly atherogenic.
A few days ago, a manuscript of an interesting trial was published. The study involved 179 patients from Sinai Hospital in Baltimore. What the study confirmed, was the notion that not LDL is dangerous – the more small LDL particles (particularly the LDL4 type) there are in the patient’s blood profile the higher the risk of coronary artery disease. This should change the cholesterol and hyperlipidaemia paradigm substantially – not everyone with high cholesterol is in danger and not everyone with normal cholesterol level is safe (Chaudhary et al., 2017).

CHAUDHARY, R. et al. 2017. LDL4: a novel predictor of coronary artery disease severity. Current Medical Research and Opinion, vol., no., pp. 1-17.