“Bad” cholesterol (LDL) has been the target of doctors for decades, who believe that reducing it will have a direct positive impact on reducing cardiovascular risk and premature death.
But a new US scientific study disproves this belief, as it shows that in practice most research to date has not confirmed these expected benefits.
Cholesterol-lowering drugs – the most popular statins in the world – are prescribed to millions of people around the world. Those with poor cardiovascular health, those with “bad” cholesterol above 190 mg / dl, those with diabetes and those with a risk of more than 7.5% for a heart attack or stroke within the next decade are considered to be the most potential beneficiaries. a number of risk factors such as age, family history, smoking, etc.)
But while lowering LDL cholesterol is considered a key component of preventative treatment, a new study published in the British medical journal BMJ Evidence Based Medicine, led by Dr. Robert DiBroff of the Department of Cardiology at the University of New Mexico, does not confirmed this.
The study systematically evaluated all published clinical trials – a total of 35 – comparing placebo with one of the three classes of cholesterol drugs (statins, ezetimibe, PCSK9). It was found that more than three quarters of clinical trials had no positive effect (reduction) on the risk of cardiovascular death, while almost half did not show any positive effect (reduction) on the risk of future cardiovascular disease.
Of the 35 clinical trials tested, 13 managed to bring LDL to the desired low levels, but only one study reported a positive effect (reduction) on the risk of death. Of the remaining 22 clinical trials that did not meet the LDL reduction target, only four reported a reduction in the risk of premature death.
In addition, the degree of reduction in “bad” cholesterol did not appear to be related to cardiovascular benefits, and even very small changes in LDL levels in the blood were associated with greater reductions in the risk of heart attack or death, and vice versa, ie large reductions in LDLs are associated with only a small reduction in cardiovascular risk.
Therefore, according to the researchers, focusing on “bad” cholesterol is an ineffective strategy, which fails to identify many high-risk people, while instead leading to prescribing drugs to low-risk people who do not actually need treatment.
Because LDL is thought to be essential for cardiovascular disease, “reducing it seems reasonable,” according to the researchers. But they add: