Age. The most common cause of high cholesterol levels in blood is increasing age. One cannot compare a cholesterol value of 240 mg/dL in a 12-year-old child with that of a 75-year-old adult. Ideal cholesterol levels depend partly on each individual’s age.
Obesity. Cholesterol levels also depend on lifestyle. Being overweight or obese and overeating and/or following an unhealthy diet with too much processed and sugary foods are the most frequent causes of hypercholesterolaemia. This is because there is an imbalance between cholesterol intake and what the body actually needs. As such, cholesterol starts to accumulate because not all of it is eliminated.
Genetic causes. These correspond to primary hypercholesterolaemia. In this case there is a defect in the tools the body uses to store or distribute cholesterol, which means they function less effectively and subsequently cholesterol accumulates. Genes are partly responsible for these high cholesterol levels, in the same way they are partly responsible for family height, for example. The cause of secondary hypercholesterolaemia depends on the nature of the underlying disease.
Risk factors associated with Hypercholesterolaemia
The risk factors for hypercholesterolaemia are the same as those which cause associated complications, in other words, cardiovascular diseases that develop due to atherosclerosis (atheromatous plaques in the arteries) such as heart attacks, strokes or a lack of blood supply to the limbs.
Having a parent or sibling who has had a cardiovascular problem (heart attack) before the age of 55 (in men) or 60–65 (in women).
Accordingly, when assessing if an individual’s cholesterol levels are acceptable, it is important to know whether or not they have other risk factors or previously had a cardiovascular problem. Thus, for example, a cholesterol level of 230 mg/dL could be normal for a 70-year-old who does not have any previous risk factors, but the same value could be very high for someone who has one or more risk factors, and in particular, for someone who has suffered a cardiovascular problem.
To decide whether a cholesterol level is acceptable, high or very high, it is crucial to define the person’s overall cardiovascular risk, which depends on their age, as well as their risk factors.