Recently, new research from Yale University has shown that the injury to the cells that line blood vessels, which are also known as endothelial cells, maybe the reason for severe coronavirus infection or death. The findings, which appear in the journal The Lancet Haematology, are important as they may explain blood clotting in patients, a complication related to death due to severe form of coronavirus.
In addition, the research can also help health professionals in conducting prior testing for endothelial damage, also called endotheliopathy. This step can help in predicting whether a patient will develop a severe form of COVID-19 as well as the chances of survival.
To investigate the key drivers of COVID-19 severity, the researchers looked at a total of sixty-eight patients, all of whom were admitted to Yale-New Haven Hospital after testing positive for coronavirus infection. Out of these, forty-eight had a severe form of coronavirus, twenty had chronic COVID-19 and thirteen were part of the control group.
In the observed patients, the researchers examined specific factors that indicate endothelial damage in order to compare it with the severity of the infection and predict survival chances. In patients with both severe and non-severe forms of the infection, endothelial damage markers were high.
Nearly all critically-ill patients had endothelial damage. On the other hand, over eighty-percent of the patients who did not have a severe form of coronavirus had signs of endothelial injury as well. The higher levels of damage in the patients were seen to be associated with lower chances of hospital discharge as well as survival.
Prior to this research, other studies had found evidence of a higher blood clotting risk in patients with severe COVID-19. For instance, a Dutch study concluded that nearly thirty-one percent of the studied patients who were in the intensive care unit had blood clotting. Many of these patients had high levels of clotting even though they were already given doses of blood thinner medication
In addition, doctors at Mt. Sinai in New York as well as LSU found blood clotting in the lungs of patients who tested positive for coronavirus along with a high incidence of stroke among the younger patients.
Dr. Alfred Lee, who is an associate professor of medicine (hematology) and director of the hematology/oncology fellowship program at Yale and one of the senior investigators of the study explains “Recognizing this increase in blood clotting risk, at the time that we began our study, a couple small autopsy series had found evidence of endothelial cell infection or inflammation in the lungs,”
“Our study is the first to measure specific markers of endothelial injury in the blood and demonstrate that endotheliopathy is common in COVID-19, especially when patients are critically ill.” He added.
Dr. Hyung Chun, who is the co-author of the new paper and an associate professor and director of translational research in the Yale Pulmonary Vascular Disease Program, explains that most doctors do not test coronavirus positive patients for endothelial damage.
The findings of the study highlight that testing for endothelial injury, specifically in patients with a severe form of coronavirus can be beneficial in decreasing the chances of related complications including blood clotting, stroke, and the risk of death.
Now, there is a need for understanding the mechanisms that damage the endothelial cells. After finding the causes of the damage, medicinal interventions can help in reducing the risk of injury.