Study Finds New Reason Why COVID-19 Harms More Men Than Women

Men are more likely to catch COVID-19 and develop serious symptoms than women because of their blood. That is according to a new study that found high levels of a special enzyme in men’s blood, which allows the novel coronavirus to infect more cells and cause infections. 

The study, published in the European Heart Journal, shows that high concentrations of angiotensin-converting enzyme 2 (ACE2) in the blood make men more vulnerable to COVID-19. With more ACE2, the virus could invade healthy cells easier than in women. 

The findings come from the analysis of blood samples from more than 3,700 heart failure patients from 11 countries across Europe. ACE2 can be found in the lungs, the heart, kidneys and the tissues lining blood vessels.

But high levels of the enzyme also appeared in the testes of men. Researchers said that potentially caused their higher ACE2 concentrations and why men are more vulnerable to COVID-19.

“ACE2 is a receptor on the surface of cells. It binds to the coronavirus and allows it to enter and infect healthy cells after it has been modified by another protein on the surface of the cell, called TMPRSS2,” Adriaan Voors, lead researcher and a professor of cardiology at the University Medical Center Groningen in the Netherlands, said in a statement. “High levels of ACE2 are present in the lungs and, therefore, it is thought to play a crucial role in the progression of lung disorders related to COVID-19.”

The study also shows that patients who took drugs like angiotensin-converting enzyme (ACE) inhibitors or angiotensin receptor blockers (ARBs) did not have higher concentrations of the enzyme in their blood.

Earlier studies suggested that such medications could increase ACE2 in the blood of patients with heart problems. That means people who take the drugs are more likely to catch COVID-19.

“Our findings do not support the discontinuation of these drugs in COVID-19 patients as has been suggested by earlier reports,” Voors said. “We found no evidence that ACE inhibitors and ARBs were linked to increased ACE2 concentrations in plasma.”

However, the team noted the study has some limitations. They only focused on blood samples from heart failure patients and the patients who did not have COVID-19.

Researchers also only used plasma and not tissues to determine levels of ACE2 in patients. The presence of the enzyme in lung tissues mainly contributes to viral infection of the lungs and not those found in the blood.

Coronavirus & COVID-19 An artist's representation of the novel coronavirus that causes the COVID-19 disease. Pixabay