Highly sensitive biomarkers for brain injury were found elevated in patients with severe COVID-19
Certain blood-based biomarkers which indicate injury to the brain were found raised in moderate to severe COVID-19 patients, according to a new study. Findings were published in the journal Neurology.
Some people infected with the coronavirus SARS-CoV-2 get only mild, cold-like symptoms, while others become severely ill and require hospital treatment.
Although the neurological symptoms associated with COVID-19 have received much less attention than the lung symptoms, most studies suggest that they are common among people with severe illness. Most common neurological symptoms include headache, dizziness, altered levels of consciousness, uncoordinated muscle movements, seizures, and strokes.
Confusion and an inability to wake up or stay awake, has been listed by CDC as a warning sign of emergency in COVID-19 patients.
NfL (neurofilament light chain protein), which is also seen in brain injury was found elevated in most of the patients who required ventilator treatment
In this study, researchers collected blood samples from 47 patients with mild, moderate and severe COVID-19 in the course of their hospital stay. These samples were analyzed by means of highly sensitive biomarkers for brain injury. The results were compared with those from a healthy control group comprising 33 people matched by age and sex.
A biomarker, known as GFAP (glial fibrillary acidic protein), which is normally present in brain cells called astrocytes, but leaks out in the event of astrocytic injury or overactivation, was raised even in moderate COVID-19 – that is, in patients admitted to hospital but not in need of ventilator support.
The second biomarker investigated was NfL (neurofilament light chain protein), which is also seen in brain injury was found elevated in most of the patients who required ventilator treatment, and there was a marked correlation between how much they rose and the severity of the disease.
“The increase in NfL levels, in particular, over time is greater than we’ve seen previously in studies connected with intensive care, and this suggests that COVID-19 can in fact directly bring about a brain injury. Whether it’s the virus or the immune system that’s causing this is unclear at present, and more research is needed, added the authors.
“Blood tests for biomarkers associated with brain injury could be used for monitoring patients with moderate to severe COVID-19, to reduce the risk of brain injury. It would be highly interesting to see whether the NfL increase can be slowed down with new therapies, such as the new dexamethasone treatment that’s now been proposed,” said Magnus Gisslén, Professor of Infectious Diseases at Sahlgrenska Academy.