In line with NICE Clinical guideline 181 – Lipid Modification: cardiovascular risk assessment and the modification of blood lipids for the primary and secondary prevention of cardiovascular disease- we have started reporting non-HDL cholesterol.
The following relevant items have been extracted from the guideline:
1.3.4 Before starting lipid modification therapy for the primary prevention of CVD, take at least 1 lipid sample to measure a full lipid profile. This should include measurement of total cholesterol, HDL cholesterol, non-HDL cholesterol and triglyceride concentrations. A fasting sample is not needed.
1.3.8 Arrange for specialist assessment of people with total cholesterol concentration of more than 9.0 mmol/L or a non-HDL-cholesterol concentration of more than 7.5 mmol/L even in the absence of a first degree- family history of premature coronary heart disease.
1.3.28 measure total cholesterol, HDL cholesterol and non-HDL cholesterol in all people who have been started on high-intensity statin treatment at 3 months of treatment and aim for a greater than 40% reduction in non-HDL cholesterol.
Non-HDL cholesterol is a calculation (Total cholesterol minus HDL cholesterol).
During the first assessment of the patient it provides an estimate of all the lipid particles associated with atherogenesis (LDL-cholesterol and triglyceride remnants).
The reason for incorporating this test into the lipid profile is to account for the atherogenic cholesterol carried by VLDL and IDL (intermediate density lipoprotein) particles.This of particular importance in patients with combined hyperlipidaemia (both raised triglycerides and LDL-cholesterol) and type II diabetes. Item 1.3.8 of the NICE guideline (mentioned above) aims to detect patients with combined hyperlipidaemia of hereditary origin.
Patients treated with statins who have achieved LDL-cholesterol targets can often be left with an elevated residual CVD risk due to the incomplete clearance of remnant atherogenic lipid particles. Non-HDL cholesterol provides a measure of these particles. Item 1.3.28 of the NICE guideline (mentioned above) aims for the clearance of residual atherogenic particles.