An interdisciplinary team of 40 scientists from Germany has found possible causes for more severe Covid-19 courses in patients with high blood pressure. The researchers also found that ACE inhibitors could possibly have a positive effect on the course of infection with Sars-CoV-2. The study was published in the journal Nature Biotechnology at the end of December. The well-known Charité virologist Christian Drosten was also involved.
High blood pressure affects a lot of people. According to the Robert Koch Institute, around 9.4 million deaths worldwide are due to high blood pressure, also known as hypertension. The most important risk factors for high blood pressure are a lack of exercise, obesity, an unhealthy diet, stress and increased alcohol consumption.
Since the beginning of the pandemic, high blood pressure has been a relevant risk factor. This also affects a lot of people in Germany. According to estimates by an RKI report, around 20 to 30 million people in this country have high blood pressure.
Often a severe course of Covid-19 with high blood pressure
But why do people with high blood pressure often get more severe from Covid-19 and therefore also have a higher risk of death? For their findings, the research team took a detailed look at the immune response of some patients. They examined 114,761 cells from 48 patients – 32 of them Covid-19 sufferers and 16 healthy people as a control group. All of them had high blood pressure.
The result: The cause of a complicated Covid-19 course is often an excessive reaction of the immune system. And this reaction is probably promoted by the fact that the immune cells are already noticeably pre-activated by the high blood pressure. High blood pressure patients usually show increased levels of inflammation in the blood, which, according to the study, can have fatal consequences in the case of a Sars CoV-2 infection. “Regardless of the cardiovascular status, increased inflammation levels are always a warning signal that the Covid 19 disease will be severe,” said Prof. Ulf Landmesser from the Berlin Charité in a statement.
Medication: antihypertensive drugs as therapy in the pandemic?
Up until now, there have been concerns among medical professionals that people who receive drugs such as ACE inhibitors or angiotensin receptor blockers to lower high blood pressure may have more ACE2 receptors on their cell surfaces – and that patients could become more easily infected with Sars-CoV-2 as a result . The Charité researchers are now giving the all-clear with regard to their investigations. “Our study does not provide any indications that treatment with drugs to lower blood pressure increases the risk of infection for the novel coronavirus,” says Landmesser. The agent is unlikely to make it easier for the virus to enter the cells.
Instead, the results of the study suggest that treating high blood pressure with ACE inhibitors could actually be beneficial for patients who contract Covid-19 and reduce the risk of a serious course of the disease. They could contain the viral load more quickly and the host cells could become more resistant. The study showed that cardiovascular patients who received ACE inhibitors had almost the same risk as the Covid-19 patients without a risk factor. The effect could not be observed to the same extent with angiotensin receptor blockers. However, the researchers admit that further studies are necessary in order to be able to present clear results.
More data is needed for therapeutic approaches
According to other experts, the data are not yet conclusive enough to have a concrete influence on the treatment of high blood pressure patients in the pandemic. “The number of study participants was too small and the study wasn’t even designed to be able to compare different antihypertensive therapies with regard to their ‘anti-Covid-19 potential'”, says Prof. Ulrich Wenzel, chairman of the board of the German Society for Hypertension and Prevention, in One Communication.
The main finding of the study for him is that high blood pressure is an independent risk factor for severe Covid-19 courses if he is not treated and the increased inflammatory reaction found could be responsible. “We hope that this central message will motivate patients to take their blood pressure medication consistently,” appeals Wenzel.