What Severe COVID-19 Does to the Brain

What you need to know

COVID-19 causes a wide range of symptoms that affect many different organs and systems of the body. For many people who become infected, one of the first signs is a bad headache. A new study shows that this is just one of many common neurological effects of the disease.

What did the researchers do?

The study analyzed health information from 3,744 people who had been hospitalized with COVID-19. Participants were identified through the Global Consortium Study of Neurologic Dysfunction in COVID-19 and the European Academy of Neurology’s (EAN) Neuro-COVID Registry (ENERGY).

The researchers looked at the participants’ hospitalization records for many possible neurological effects, including self-reported symptoms — such as headache and loss of taste or smell — and symptoms observed by hospital staff, such as fainting, coma, seizure, encephalopathy (brain damage), meningitis, and aphasia (difficulty remembering words).

What did they learn?

Neurological effects were extremely common, appearing in about 80% of patients who had been hospitalized with COVID-19. The most common symptoms reported by patients were headache, which affected 37% of participants, and loss of taste or smell, which affected 26%. The most common neurological problems observed in patients by hospital staff were acute encephalopathy (affecting 49% of patients), coma (17%), and stroke (6%).

Patients whose neurological symptoms were observed by hospital staff were more likely to die in the hospital than people with self-reported neurological symptoms — likely because symptoms reported by hospital staff occur in more severe cases of COVID-19. The researchers also found that people with preexisting neurological conditions such as chronic migraines, brain or nerve diseases, or dementia were more likely to have neurological symptoms of COVID-19 than other people were.

Why is this research important?

Understanding how COVID-19 affects the brain may help researchers better understand how the disease works, how to spot symptoms earlier, and how to treat it and any lasting effects the disease may cause.

Where can I go to learn more?

Sniffing Out COVID-19

• Loss of taste or smell is a common neurological symptom of COVID-19. New tests may use this symptom to help identify infections more quickly.

Coronavirus and the Nervous System

• The National Institute of Neurological Disorders and Stroke shares current research on the effects of COVID-19 on the brain and nervous system.

Symptoms of COVID-19

• The Centers for Disease Control and Prevention provides information on common symptoms of COVID-19.

Sources

Chou, S. H. Y., Beghi, E., Helbok, R., Moro, E., Sampson, J., Altamirano, V., Mainali, S., Bassetti, C., Suarez, J. I., & McNett, M. (2021). Global Incidence of Neurological Manifestations Among Patients Hospitalized With COVID-19 — A Report for the GCS-NeuroCOVID Consortium and the ENERGY Consortium. JAMA Network Open, 4(5), e2112131. https://doi.org/10.1001/jamanetworkopen.2021.12131