Cholesterol has been losing weight as an indicator of health over the years.
At least, if it is taken in isolation, without taking into account other parameters.
Some serious studies downplay its ability to predict cardiovascular events in healthy people, but the consumption of pills to reduce it does not stop growing throughout the world, including Spain, where it has increased by 50% in a decade, according to data from the Agency Spanish Association of Medicines and Health Products (AEMPS).
In 2021, 134 doses were consumed per 1,000 inhabitants per day.
Are they too many?
"Perhaps we shouldn't ask if there are many or few, but if we are taking them well," answers Daniel Escribano, coordinator of the Dyslipidemia group of the Spanish Society of Family and Community Medicine (semFYC).
He argues that people most at risk of cardiac events are probably even under-medicated, while some less likely to have them may be taking them unnecessarily.
Low cholesterol yes or yes, and the more the better, has become an old dogma.
At least, today scientific evidence conditions it to many other factors.
If it acquired this fame as the key parameter to take into account in an analysis, it was because it was discovered that its presence in the blood was associated with the risk of cardiovascular events.
But it is a relatively recent field, with barely a few decades of history, which has been acquiring nuances (which does not mean that it is irrelevant).
Actually, what the analyzes measure is not cholesterol (which is not only bad
per se
, but essential for life), but indirect indicators: the lipoproteins that transport it through the blood.
There are not different types of cholesterol, but these lipoproteins.
And one of them, LDL, in large amounts, can cause atherosclerosis, the accumulation of fat in veins and arteries that can lead to heart attacks or strokes, among other events.
Before the covid, ischemic heart and cerebrovascular diseases were the leading causes of mortality in Spain.
In 2021, 53,710 people died because of him.
As the differences between the types of lipoproteins became known, it was found that the risk of these events was not so much associated with cholesterol itself, but with this last type of lipoprotein, which is commonly known as bad cholesterol, LDL.
What lipid-lowering drugs, commonly known as statins, do is precisely lower LDL levels and, therefore, coronary risk.
At least, this is the theory.
As José Abellán, a cardiologist at the Hospital General Universitario Santa Lucía de Cartagena (who spreads about health on Instagram) explains, there is a very solid consensus that, in people who have already suffered a cardiovascular event, keeping LDL low is essential to prevent they repeat themselves
“I work with these types of patients and practically all of them take statins, which are very beneficial for them,” he points out.
The nuances arrive above all in healthy people, or without other risk factors.
A review of studies on the subject published in 2022 concluded that the benefits of lowering LDL levels with statins are "modest" for the general population.
If the subjects that included all the studies were divided into two large groups, one treated with these drugs and the other with placebo, the relative reduction of the first would be 9% for all causes of mortality, 29% for heart attack myocardium and 14% for cerebrovascular accident.
Explained like this, they sound like enough to take the medication, but in absolute terms, the reductions were much smaller: 0.8%, 1.3% and 0.4%, respectively.
What is the difference between relative and absolute risk?
In a hypothetical disease that causes 1% mortality, a drug that lowers it to 0.8% has reduced the relative risk by 20%, but the absolute risk by only 0.2 points.
A person suffering from the ailment and taking the drug goes from having a very low chance of dying to having a little less;
the difference in your prognosis is statistically very small, but that little bit is a 20% reduction.
And although the personal risk hardly changes, this percentage taken in an entire population is large: if a million people get sick (of which 10,000 would die), the medicine can save 2,000 lives.
To know if it is worth prescribing or not, the side effects would have to be measured, since the risk may outweigh the benefit.
Paula Byrne, one of the authors of the meta-analysis on the benefits of statins, explains it very graphically in an article published in December.
In two groups of 1,000 people with high cholesterol each, one treated with drugs and the other with placebo, the vast majority of them did not suffer a cardiovascular event in any case.
In those who take an innocuous substance there are 45 serious events, while those who receive lipid-lowering drugs register 32.
If statins were free of side effects, there would be no question that these 13 events (including eight deaths) are worth avoiding.
But, like any medicine, it has them and sometimes they are not mild.
In Byrne's example (this time with real data, not hypothetical), more than 950 people who were not going to suffer any complications in any case are being medicated in both groups.
For this reason, the authors recommend that patients be informed of these statistics so that they can make their decisions, in addition to taking them into account in clinical guidelines.
The truth is that the guidelines have changed and have been adapted to the evidence.
In the last 15 years, the recommended cholesterol levels have been changing.
Escribano explains that the number that indicates cholesterol is no longer an absolute reference, but that risk factors such as sex, age, stress, physical activity, diet and whether or not the patient is a smoker are taken into account. as well as personal and family history.
Someone who is young, healthy and active will be able to afford higher LDL levels than a sedentary smoker whose father has died of a heart attack, for example.
This guide, called
Score2
, was updated in 2021, adapting to the new knowledge that has emerged.
With it in hand, doctors should not prescribe statins simply because of high cholesterol, but taking all these factors into account and only if other approaches have failed, which is also not entirely new.
The problem, Abellán believes, is that the health system is not designed for prevention: “With the time we have for patients and the appointments we can give them, it is impossible to guide exercise and eating patterns and follow them to see how they evolve.
Given this, perhaps pills are used as an apparently simple measure to lower cholesterol.
This is a problem for doctors, but also for patients.
"Sometimes the attitude seems to be that if the doctor does not prescribe anything, it is not good, and we want the easy solution, not to take responsibility for my health, but to fix it with medicines," continues the cardiologist, who believes, however, that the situation is slowly changing.
Types of cholesterol that are not measured
The guides, in any case, are not mathematics;
health is not an exact science.
There are borderline situations, with high values and medium risk levels, in which there is no clear solution.
For them, standard blood tests may fall short.
Within the large types of lipoproteins there are other subtypes and other substances that are not measured and could help clinical decisions.
LDL-P (a type of LDL) is a more accurate indicator of risk and can be calculated by measuring a protein called APOB that is not included in conventional tests.
Another type of cholesterol that is not normally analyzed is lipoprotein A, the amount of which can also help decide which treatment to take in patients who are not clearly at high or low risk.
"The guidelines say that it should be determined at least once in a lifetime to verify cardiovascular risk, but this is not always possible," says Escribano.
As with many other tests, according to the autonomous community, primary care physicians can sometimes request this type of analysis and sometimes not.
“Sometimes it even depends on your trust in the laboratory technician, who some doctors ask as a personal favor for their patients.
There is no homogeneous criterion ”, he continues.
In any case, the person in charge of dyslipidemia at semFYC assures that for the majority of the population it is not necessary to nitpick and that, if you do not have major risk factors or some genetic predisposition to rare high cholesterol, diet and exercise should be the
medicine
for the majority who have not suffered a cardiovascular event.
As with mental health, perhaps more cholesterol pills are taken than necessary because the system, as a whole, fails to influence other, healthier and more effective pathways.