Invisible Lipoprotein A: Sneaky heart risk

By Daniella Egbujor, Student Pharmacist and Karen L. Kier, Pharmacist
ONU Healthwise Pharmacy

Invisible Woman is a superhero from The Fantastic Four introduced by Marvel Comics in 1961.  Dr. Susan Storm Richards was transformed into the Invisible Woman by cosmic rays in the first issue of The Fantastic Four. This power not only gave her the ability to be invisible, but she has the power to use force fields.

Lipoprotein A may be the invisible force behind cardiovascular (heart) disease!

LDL cholesterol (bad cholesterol) is well known to cause heart disease. There are many different medications on the market to help control LDL cholesterol including the most utilized drugs atorvastatin and rosuvastatin (statins).

But what if we told you that there is another cholesterol-like particle that is more dangerous? 

Meet lipoprotein A (Lp(a)), the troublemaker working behind the scenes. What does it do?

It increases the risk of heart disease, strokes, and heart attacks. It looks a lot like LDL cholesterol, but it has an extra protein attached to it called apolipoprotein(a), which makes it sticky and easier to clump in blood vessels and cause blockage. It is often referred to as a triple threat because it can cause inflammation and blood clots.

The most difficult aspect is the inability to control it with diet, exercise or even cholesterol medications, because it is mainly caused by your genetics. You can get your Lp(a) levels checked through blood testing; it is not part of a standard cholesterol panel, so you would have to ask for it. Current cholesterol medications, like statins, help lower LDL cholesterol but are not as effective against LpA levels.

Lp(a) is a tricky player of the heart; it is not easily broken down or cleared out because it has a unique structure. This unique structure is part of the research to find drugs to manage Lp(a) cholesterol. Some receptors on the structure help to remove it, while one, a plasminogen receptor KT (PlgRKT), even recycles part of it, allowing it to form new Lp(a) particles. This recycling process explains why high Lp(a) levels are difficult to control and a stubborn risk factor for heart disease. 

Managing lipoprotein A levels can be challenging, but it is not impossible. Maintaining a healthy diet and exercise regimen may not have much effect on bringing down Lp(a) levels, but it is great for your overall heart health! The FDA has not approved any drugs to help with lowering Lp(a) levels, but commercially available PCSK9 inhibitors (PCSK9) show some promise. 

PCSK9 inhibitors such as alirocumab (Praluent) and evolocumab (Repatha) are cholesterol lowering drugs blocking the PCS protein. They mainly lower LDL cholesterol, but can reduce Lp(a) levels by about 25%. There are new treatments which have similar mechanisms as the PCSK9 inhibitors. One of these is inclisiran (Leqvio), which improves cholesterol levels and lowers Lp(a) by about 20%.

Research is ongoing to develop Lp(a) lowering drugs.

While Lp(a) levels may still be invisible, you can control your overall heart health. Focus on lowering LDL, living a heart-healthy lifestyle, and keeping other risk factors in check.