Blood tests could be early indicator of COVID-19 severity: study
Blood samples are seen in this file photo. (Henrik Dolle/Istock.com)
TORONTO -- A new study says that blood tests may be the key for doctors to get an idea of what to expect when treating COVID-19 patients.
Often, when a COVID-19 patient is admitted to the hospital, there’s no clear indicator of how severe their disease may become, if they’ll require ventilation, if their stay will be days or weeks, or if they’ll make it out alive. A new test aims to answer those questions once patients arrive at the hospital.
The study, published Friday in Blood Advances, found that certain elevated “biomarkers,” which are an indicator of disease, could predict a diseases’ severity, but researchers say further study is needed.
The biomarkers researchers looked at are called neutrophils, a type of white blood cell that fights infections and can be associated with inflammatory diseases, such as obesity and diabetes.
"Patients with high levels of these markers were much more likely to require care in the intensive care unit, require ventilation, or die due to COVID-19," said lead study author and Yale professor Dr. Hyung Chun in a press release.
Previous studies looking to identify markers of severity of COVID-19 had looked at various levels of biomarkers indicating levels of blood coagulation and inflammation.
The study screened multiple proteins in the blood from 100 COVID-19 patients and looked at clinical data from 3,000 patients in Yale’s hospital system.
The findings show that five proteins associated with neutrophils, a type of white blood cell that fights infections, were elevated in the patients with COVID-19 who later became critically ill, the study said. Neutrophils are normally associated with obesity and inflammatory disorders – this is the first time they have been linked to COVID-19 or other viruses.
Elevated neutrophil levels were present in patients before any onset of severe symptoms, researchers found.
“Inflammation sets the stage for ARDS, acute respiratory distress syndrome. Any condition that increases inflammation is going to increase risk,” Toronto physician and clinical researcher Dr. Iris Gorfinkel told CTVNews.ca in a phone interview on Saturday.
Doing activities to promote the reduction of inflammation in the body will be beneficial for COVID-19 outcomes, including losing weight, quitting smoking, getting a proper sleep and regular exercise, Gorfinkel said.
All of the patients in the study who had elevated neutrophil markers ended up in the ICU, while those with low neutrophil markers did not- and none of those with lower markers died.
"If a diagnostic test could be ordered early, it could give us a better sense of who is more likely to become critically ill and will benefit from a higher level of care and consideration for therapies that affect the immune system early on in their hospitalization," said Chun in the press release.
While this study is a great “jumping off point” and knowing disease severity before it happens could save lives, Gorfinkel said more research needs to be conducted to determine if neutrophils are independent markers for COVID-19 severity.
“We need a way to predict who is going to wind up in hospital,” she said.
Researchers noted they plan to expand their study into the relationship between biomarkers and COVID-19 by looking at patients who have recovered from acute illnesses.
The study also underscores the connection between COVID-19 and obesity, researchers said. The U.S. Centers for Disease Control and Prevention notes that obesity and severe obesity increase risk of severe illness from COVID-19, with triple the risk of hospitalization from the disease.