Were you aware that there are two new medications approved to treat high cholesterol levels? Traditionally, patients and physicians have relied on the statin class of medication to lower LDL or “bad” cholesterol levels. The most well known of these is Lipitor (you may have seen the commercials). The newer medications are delivered by injection and are in a class called PCSK9 inhibitors.
The new PCSK9 inhibitors can achieve LDL levels far lower than can be achieved by even the highest intensity statins. Whereas one might expect to lower an LDL to under 100mg/ml or under 70mg/ml with Lipitor, studies show that the PCSK9 inhibitors can achieve LDL levels below 25mg/ml. In one study 9% achieved levels under 15mg/ml!
But we must need some cholesterol in the body, right? It must serve some function and, correctly, some researchers are concerned that very low levels of LDL could adversely affect the production of sex steroid hormones and adrenal hormones which rely on cholesterol.
However, a recent study (http://www.onlinejacc.org/content/69/5/471) analyzed 5,234 patients treated for up to 2 years and examined the occurrence of adverse events. There was no increase in a wide variety of conditions including neurologic, memory, kidney, liver or diabetes. However, the authors did see (pun intended) an increase in cataracts among those patients with LDL levels below 25mg/ml.
So is there such a thing as ‘too low’ cholesterol? Other than the risk of cataracts, so far there does not seem to be a downside.