How to read cholesterol analysis

The results come from the laboratory. The verdict: We have high cholesterol. That is why war must not be declared on him immediately. Because not all cholesterol comes to harm.

“Good” cholesterol and “bad” cholesterol are terms that have now entered everyday use and it is generally known that hypercholesterolemia, i.e. high levels of this fat in the blood, can represent a health risk factor that should not be underestimated.

However, since it does not generally give symptoms, to find it you must periodically undergo a blood test.

It is an easy and fast test, but interpreting the report is not so simple, also because it is often not enough to consider the values examined individually, but it is necessary to read them as a whole and also take into account the characteristics of individual patients.

In general, the guidelines give limits for cholesterolemia:

Values too high	Total cholesterol > 240 mg/dl
Optimal values	Total cholesterol < 200 mg/dl
Optimal values in subjects with heart disease or high cardiovascular risk	Total cholesterol < 160 mg/dl

But these data are often not enough to make us worry more than we should by rushing to eliminate foods on foods and running to look for remedies that defeat this lipid.

It should not be forgotten, however, that cholesterol, in the right quantities, is not only not harmful, but is even necessary.

It performs essential functions for our body and its excessive reduction would in some cases also be counterproductive.

It is necessary to know how to distinguish

Cholesterol is a substance that belongs to the family of lipids, in other words a fat, known to most to be an enemy of the body.

In reality, cholesterol is necessary for the proper functioning of the body: it participates, for example, in the synthesis of certain hormones and vitamin D and is a constituent of cell membranes and bile, the liquid secreted in the liver fundamental for digestive processes and for the elimination of bilirubin, in turn produced by the degradation of hemoglobin (protein containing iron which allows red blood cells to carry oxygen to all tissues).

Cholesterol is partly secreted by the liver (endogenous cholesterol), while a part can also be introduced with food (exogenous cholesterol): it is contained, for example, in foods rich in animal fats, such as meat, butter, cold cuts, cheeses, egg yolk, liver. It is absent in fruits, vegetables and cereals.

The transport of cholesterol through the blood is entrusted to a particular class of particles, lipoproteins, so called because they consist of proteins and a lipid component.

The most important for cardiovascular prevention are:

Lipoproteins	Function
Low density (LDL)	They transport synthesized cholesterol from the liver to the cells of the body
High density (HDL)	They remove excess cholesterol from the tissues and transport it back to the liver, which then eliminates it.

When it comes to cholesterol, therefore, it is always good to keep in mind that there are essentially two types: the bad one (Ldl) and the good one (Hdl).

The first, transported to the periphery by low-density lipoproteins, called LDL cholesterol, attaches more easily to the inner walls of the arteries, causing a progressive thickening and hardening. For this reason, an excess of bad cholesterol in the blood is among the causes of atherosclerosis, a process that can lead over time to the formation of plaques (consisting of a central core of cholesterol and a sort of cap of fibrous tissue) that hinder blood flow. Over time, plaques (also called atheromas) can rupture: this phenomenon recalls platelets and coagulation factors that favor the formation of a thrombus which, in turn, can completely obstruct the artery and therefore block the passage of blood.

Depending on where this process takes place, you can experience different pathologies: a heart attack (at the level of the heart), a stroke (at the cerebral level) or an intermittent claudication (at the level of the legs).

On the contrary, the cholesterol transported by high-density lipoproteins, therefore called HDL cholesterol, plays a contrary action: it is able to capture the excess deposited on the arterial walls bringing it back to the liver, where it is eliminated.

This is why, if it is true that total cholesterol levels in the blood should not exceed 200 mg / dl (160 mg / dl if other cardiovascular risk factors are present) it is equally important, in case of hypercholesterolemia, to investigate more deeply.

A simple withdrawal is all it takes

 

The measurement of cholesterol levels requires a simple blood sample for which it is not required to be fasting, which is necessary, for example, for other blood tests, such as the one aimed at assessing blood glucose, ie the levels of glucose in the bloodstream, and for urine tests.

In fact, it has been shown that cholesterolemia measured on an empty stomach is comparable to that measured on a full stomach.

Absolute and relative values

We speak of hypercholesterolemia when the total cholesterol is too high (the desirable values, as already mentioned, are considered as such below 200 mg / dl).

Finding high total cholesterol is not, however, necessarily worrisome. Even more so if there are no other risk factors for cardiovascular disease.

The most correct thing to do, in the presence of hypercholesterolemia, is to evaluate the values of the different types of cholesterol and, above all, their ratio.

In particular, the tables say that:

– optimal LDL values should be within 100 mg/dl

– optimal HDL values should be equal to or greater than 50 mg/dl.

Cardiovascular risk index

But even this may not be enough when assessing the “weight” of cholesterol as a cardiovascular risk factor.

First of all, the relationship between the values of total cholesterol and those of HDL (which should be indicated in blood tests) must be calculated.

This ratio, which represents the cardiovascular risk index for healthy people and in the absence of associated risk factors, must be:

– less than 5 in humans

– less than 4.5 in women.

In general, the higher the HDL, the lower the risk of cardiovascular disease.

Finally, in the case of high cholesterol in the blood it would be correct to consider another type of fat: triglycerides.

Their high levels in the blood increase the risk of coronary heart disease and atherosclerosis and, almost always, are associated with low HDL cholesterol and other risk factors, such as the tendency to overweight, obesity, diabetes and hypertension.

Knowing the levels of triglycerides also allows you to calculate more precisely the level of LDL cholesterol, which is usually not expressly indicated on the report: it is enough, for this purpose, to subtract the value of total cholesterol the value of HDL and one fifth of the value of triglycerides.

Pay attention to your level of risk

Regarding the assessment of cholesterol levels, according to the latest guidelines on hypercholesterolemia issued in 2016 by the European Society of Cardiology, it is essential to also keep in mind the cardiovascular risk profile of the patient.

In particular, desirable levels of LDL are different depending on the degree of cardiovascular risk:

– for those with a moderate risk must be below 115 mg / dl

– for those who have a high risk (such as those suffering from severe hypertension, diabetes without other risk factors, moderate renal failure or familial hypercholesterolemia, hereditary disease in which a genetic alteration causes the increase of cholesterol in the blood) must be below 100 mg / dl;

– for those who have a very high risk (such as cardiovascular patients, those who have already had a heart attack or stroke, diabetics with other cardiovascular risk factors, severe renal failure) must be less than 70 mg / dl.

In these cases, even more so, it is up to the doctor to evaluate the results of a cholesterol test.

Blood tests: if cholesterol values are altered

If the tests show an actual hypercholesterolemia, the doctor will prescribe a lifestyle change (with particular attention to nutrition and physical activity) as a first fundamental and necessary step to reduce cholesterol values. If it is not enough, it will provide therapy with drugs called lipid-lowering drugs.

It should also be said that there are factors often unknown to most that can influence the values of hypercholesterolemia and which must be taken into account to correctly evaluate the outcome of the examinations. For example, it is considered physiological an increase, even sensible, of blood cholesterol values during pregnancy, so a specific therapy may not be necessary (but it is always up to the doctor to have the last word in this regard).

There are also diseases that can contribute to raising cholesterolemia, whose treatment could allow to restore correct levels of cholesterol in the blood, without requiring specific lipid-lowering treatment.

This is the case, for example, of hypothyroidism, which develops when the thyroid does not work properly: if the doctor suspects the presence of this pathology, he can prescribe further tests, endocrinological, to confirm or not the diagnosis and proceed accordingly, in order to restore not only adequate levels of thyroid hormone, but also cholesterol.