When you have a blood test to check your cholesterol the total cholesterol, LDL, HDL and non-HDL cholesterol elements are generally measured. However cholesterol metabolism is highly complex and there are many other elements that can also be measured. One element called lipoprotein (a) is currently hitting the headlines.
Lipoprotein (a) was first identified in 1963 and has been investigated in depth, particularly recently. It is made mostly in the liver and consists of an LDL-like lipoprotein and two other proteins. It can become trapped in the arterial wall where it causes inflammatory and other changes that participate in the initiation and progression of furring up of arteries (atherosclerotic plaque). High levels of lipoprotein (a) significantly increase the risk of cardiovascular disease (angina, heart attack, stroke etc) and also narrowing of the aortic valve (aortic stenosis).
Elevated lipoprotein (a) is probably the most commonly inherited genetic risk factor for cardiovascular disease and so could be used to screen family members where one member has been identified with a high level. The plasma level is stable throughout life and is not substantially affected by diet, lifestyle or statins. Some of the newer drugs that lower cholesterol such as the PCSK9 inhibitors and inclisiran lower lipoprotein (a) to some extent and there are ongoing trials* testing new drugs which specifically target and lower lipoprotein (a). We await the results of these trials with great interest.
*Tsimikas S, Karwatowska-Prokopczuk E, Gouni-Berthold I, et al. Lipoprotein(a) reduction in persons with cardiovascular disease. N Engl J Med 2020;382:244-55.