For many years, there has been this unproven suggestion from the medical profession that high cholesterol, especially in older people, is always a major risk factor for heart disease and high cholesterol, by itself, needs to be treated. The reality is that the evidence is just not there for this concept.
Firstly, let me clear up some common myths about cholesterol. Although it is vitally important that we all follow a sensible diet, there is no major link between diet and cholesterol. I am not suggesting you can eat what you would like but the reality is that your cholesterol is more determined by genetics and metabolism then it is by food.
There is no doubt that if you consume a bad diet and have poor genetics and a lousy metabolism that your cholesterol may be significantly elevated, but equally, I have seen numerous people who consume a sensible, healthy diet with significant elevation in cholesterol levels.
In the BMJ in 2016, a large study of 68,000 people, over the age of 60, followed for 10 years showed clearly that there is no link between LDL cholesterol (the so called bad cholesterol) and cardiovascular disease but interestingly those with the higher LDLs tended to live longer, have less cancer, gastrointestinal disease and infectious disease.
A recent study from the US showed that in people over the age of 65, without a prior history of existing heart disease, who are treated with statins, had a higher death rate compared with those not treated.
So, what is the answer for this seeming paradox? Why is cholesterol probably not the big killer we thought it was, especially in older people? The answer is that not all cholesterol is equal and LDL cholesterol is not bad and HDL cholesterol is not good. Both LDL and HDL are divided into small and large components.
Here is where size is important! The larger your LDL and HDL, the more protective this is, not just against heart disease, but also cancer and other common illnesses. The reason that large LDL is protective is that it is clearly linked to building better cell membranes; cell to cell communication; an healthier blood brain barrier; is the basic ring for steroid metabolism and is vitally important for bile salt metabolism along with vitamin D metabolism. Large HDL-cholesterol is involved in what is known as reverse cholesterol transport removing cholesterol from fatty plaques in the walls of arteries. Therefore, both large LDL and large HDL are protective.
It is, in fact, small, dense LDL cholesterol which is pro-atherogenic and small HDL which is pro-inflammatory i.e. small, dense LDL cholesterol puts fat in the walls of your arteries and small HDL cholesterol inflames your arteries, contributing to the generation of atherosclerosis. Atherosclerosis is the progressive build up of fat, inflammatory cells and calcium in the wall of your arteries over decades often leading to acute rupture of one of these fatty plaques and a subsequent heart attack or stroke, depending on the location of the plaque.
Why then is high cholesterol a lesser risk factor in people over the age of 60? The answer is rather straightforward. If your cholesterol is going to get you in the first place, it is typically small LDL and HDL and it will typically affect you before age 60.
Both the small components are major factors in the generation of premature vascular disease. Statin therapy has proven benefits in people with existing vascular disease below the age of 75 but has no place in the management of cholesterol issues if you do not have significant atherosclerosis manifested by you having had a vascular event such as an heart attack, stent or a coronary bypass or one of the vascular equivalents such as a stroke or peripheral vascular disease.
The only other circumstance where treating cholesterol is important is if someone has an elevated coronary calcium score that places them in the 75th percentile of risk. As an example, if a 50 year old male has a coronary calcium score above 50 this is already significant atherosclerosis for such a young age. If a 70-year-old has a coronary calcium score of 150, this is below the normal average for that age and should be ignored.
The bottom line here is that doctors should not be treating cholesterol but rather assessing vascular risk by either establishing an history of existing vascular disease or detecting an elevated coronary calcium.
I must stress my usual point that the intravenous CT coronary angiogram is not a screening test for heart disease and has never been proven in any studies of asymptomatic people to have any benefit whatsoever over the less expensive, typically less radiation and totally non-invasive (not requiring any injections) coronary calcium score (despite using the same technology). So, if you are sent for a coronary calcium score and come at you with a needle, it is the wrong test.
Simply put, you don’t treat cholesterol, you treat cardiovascular risk.