Subset of COVID-19 patients have increased bleeding risk

February 01, 2021

The human body strives to keep itself in homeostasis, or balance. When blood clots are created, the body's innate response is to break the clots down to prevent significant health problems from arising.

Research has found that patients with COVID-19 are prone to serious blood clotting. This is why many patients receive high dose anticoagulants as part of their treatment.

But a new study in Scientific Reports, led by senior author Daniel Lawrence, Ph.D., a Professor of Basic Research in Cardiovascular Medicine at Michigan Medicine, found that aside from this heightened clotting risk, some COVID-19 patients have an unbalanced ability to break down clots as well, which is linked to a potential clinical biomarker seen in later stages of the disease.

This abnormal process of breaking down clots can contribute to a high bleeding risk, raising concerns about the current practice of giving COVID-19 patients high dose anticoagulants throughout the duration of their disease course.

This finding may be consistent with the NIH's recent decision to pause enrollment of critically ill COVID-19 patients in the Antithrombotic Therapy to Ameliorate Complications of COVID-19 (ATTACC) trial, because "a potential for harm in this sub-group could not be excluded."

"Pathological blood clotting in COVID-19 patients has been studied extensively, but recognizing and addressing the high bleeding risk in a subgroup of patients is equally important," says first author Yu (Ray) Zuo, M.D., M.S.C.S., a rheumatologist at Michigan Medicine.

Zuo, Lawrence and their colleagues sought to understand the balance between COVID-19 coagulation and the breakdown of clots to help inform approaches to treatment.

The study included 118 COVID-19 patients and 30 healthy controls. In the COVID-19 patients, the team expected to see high levels of plasminogen activator-inhibitor-1, a molecule associated with stabilizing blood clots. However, they didn't expect high levels of tissue-type plasminogen activator, the molecule responsible for removing the clots.

According to the researchers, almost half of the study's patients were supported by a ventilator and a quarter breathed just room air. Compared with the patients breathing room air, patients that required supplemental oxygen had significantly higher levels of plasminogen activator-inhibitor-1, but not of tissue-type plasminogen activator.

High levels of both tissue-type plasminogen activator (tPA) and plasminogen activator-inhibitor-1 (PAI-1) were associated with worse lung function, but high tPA independently correlated with mortality. The levels of either molecule can increase independently of the other, but the research also found a change in one can have consequences on the other.

The team asked whether COVID-19 plasma with the highest tPA levels might correlate with an enhanced, spontaneous breaking down of clots, as compared with low tPA COVID-19 plasma or control plasma.

Michigan Medicine - University of Michigan

Related Blood Clots Articles from Brightsurf:

New cause of COVID-19 blood clots identified
A new study reveals that COVID-19 triggers production of antibodies circulating through the blood, causing clots in people hospitalized with the disease.

Children who take steroids at increased risk for diabetes, high blood pressure, blood clots
Children who take oral steroids to treat asthma or autoimmune diseases have an increased risk of diabetes, high blood pressure, and blood clots, according to Rutgers researchers.

COVID-19 may cause deadly blood clots
COVID-19 may increase the risk of blot cots in women who are pregnant or taking estrogen with birth control or hormone replacement therapy, according to a new manuscript published in the Endocrine Society's journal, Endocrinology.

New evidence for how blood clots may form in very ill COVID-19 patients
Neutrophil Extracellular Traps (NETs) have been implicated in causing excessive clotting in cancer patients.

Researchers find new way to detect blood clots
Researchers in the Department of Biomedical Engineering at Texas A&M University are working on an entirely new way to detect blood clots, especially in pediatric patients.

High rate of blood clots in COVID-19
COVID-19 is associated with a high incidence of venous thromboembolism, blood clots in the venous circulation, according to a study conducted by researchers at Brighton and Sussex Medical School (BSMS), UK.

New tool helps distinguish the cause of blood clots
A new tool using cutting-edge technology is able to distinguish different types of blood clots based on what caused them, according to a study published today in eLife.

Hookah smoke may be associated with increased risk of blood clots
In a new study conducted in mice, researchers found that tobacco smoke from a hookah caused blood to function abnormally and be more likely to clot and quickly form blood clots.

Reducing the risk of blood clots in artificial heart valves
People with mechanical heart valves need blood thinners on a daily basis, because they have a higher risk of blood clots and stroke.

New study provides insight into the mechanisms of blood clots in cancer patients
Researchers have identified a potential new signaling pathway that may help further the understanding of blood clot formation in cancer patients and ultimately help prevent this complication from occurring.

Read More: Blood Clots News and Blood Clots Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.