Intestinal bacteria affect the risks of heart attacks and strokes

Bacteria in the gut affect heart attack risk

It has long been known that a healthy intestinal flora makes an important contribution to the protection against infections, allergies and other diseases. Researchers have now found that intestinal bacteria also have an impact on the risk of heart attack and stroke.

Number of deaths increased by heart disease

According to health experts, the number of deaths from heart disease has increased in recent years. In acute heart attacks, however, there was a decline in mortality, reported the German Society of Cardiology - Cardiovascular Research e.V. at the beginning of the year. Nevertheless, around 280,000 people in Germany still suffer from a heart attack each year, and around 50,000 of them die as a result. Researchers have now shown that certain bacterial metabolites from the gut increase the risk of suffering a heart attack or stroke.

Researchers from Germany and the US have found that certain bacterial metabolites from the gut increase the risk of suffering a heart attack or stroke. (Image: Alex / fotolia.com)

Causes and Risk Factors for Heart Attack

Among the known heart attack causes include high blood pressure, high cholesterol levels in the blood, smoking, overweight, lack of exercise and an accumulation of heart attacks in the family.

Patients who have already suffered a "cardiovascular event", ie a heart attack or a stroke, are also at particular risk.

Researchers from Germany and the USA have now investigated a less well-known risk factor in two studies involving a total of more than 600 patients who have recently had a stroke: the so-called microbiome, the bacteria in the gut.

As the Berlin Institute of Health (BIH) reports in a communication, the study of BIH Professor Ulf Landmesser with colleagues from the Department of Cardiovascular Medicine of the Cleveland Clinic in Ohio and Professor Matthias Endres and colleagues of the Department of Neurology the Charité and performed by the Hannover Medical School.

The results were published in the journal "Arteriosclerosis, Thrombosis, and Vascular Biology".

Connection between inflammation and arteriosclerosis

In particular, the researchers measured the concentration of a metabolite of the bacteria, trimethylamine oxide, and compared it to risking a heart attack or stroke.

"We found that patients with a high concentration of trimethylamine oxide in the blood were twice to five times as likely to have a heart attack or stroke as patients with a low concentration of the metabolite," said Ulf Landmesser, director of the clinic for Cardiology at the Charité Campus Benjamin Franklin and Medical Director of the Charité Center for Cardiovascular and Vascular Medicine at the Charité - Universitätsmedizin Berlin.

Apparently, the trimethylamine oxide stimulates the cells on the inner layer of the blood vessels, the endothelial cells, to form factors that promote blood coagulation and vascular inflammation.

This in turn attracts pro-inflammatory blood cells, monocytes, which in turn promote atherosclerosis and thrombosis in the blood vessel walls.

According to Landmesser a completely new idea: "The idea that inflammation is associated with arteriosclerosis, goes back to Rudolf Virchow, who has already described 160 years ago here in Berlin."

New ways of prevention

However, the recognition that microbiome and heart attack or stroke are related, also offers completely new ways to prevent these diseases.

The Berlin physicians and their colleagues from the USA have set up an international transatlantic research network of excellence to look for substances that can inhibit the formation of harmful metabolites in the bacteria.

"Conventional drugs that inhibit blood clotting, while reducing the risk of heart attack, at the same time increase the risk of bleeding," said Landmesser.

"The interesting thing about this new approach is that by influencing the bacteria, you could lower the risk of heart attack and stroke without increasing the risk of bleeding. So maybe a particularly elegant way to achieve the goal. "

Lower heart attack risk by adding food

Landmesser plans to test the findings in the next three years in a clinical trial in patients.

But that's not all: "We found even more interesting metabolites in the microbiome, which positively influence the cholesterol metabolism, for example," says the expert.

"One could orally administer such a bacterial metabolite, as a nutritional supplement, and thus reduce the risk of heart attack."

Therefore, it would be completely wrong to demonize all the roommates in the intestine, said Professor Ulf Landmesser.

"We have more bacteria in us than we have body cells. And these bacteria also do many things that are good for us. And of course we also want to research them and possibly use them in preventive approaches. "(Ad)