How COVID-19 Affects the Brain
COVID-19 is mostly known for affecting the respiratory system, causing symptoms like cough, fever, and difficulty breathing. However, research has shown that the virus can also impact other parts of the body, including the brain. A team of doctors and scientists from Columbia University and other medical institutions investigated how COVID-19 might cause neurological problems, and their findings are concerning. Even patients with mild symptoms have reported issues such as memory loss, confusion, and "brain fog," which is difficulty concentrating and thinking clearly.
How COVID-19 Enters the Brain
COVID-19 is caused by the SARS-CoV-2 virus, which primarily enters the body through the respiratory system. It uses a specific receptor on the surface of cells, called the angiotensin-converting enzyme 2 (ACE2), to enter and infect cells. While ACE2 receptors are mainly found in the lungs, they are also present in other organs, including the brain. This discovery led scientists to believe that the virus can infect the brain by traveling through the bloodstream or by entering directly through the nose.
One possible way the virus enters the brain is through the olfactory nerve, which is responsible for our sense of smell. This could explain why many COVID-19 patients experience a loss of smell early in their infection. The virus may also cross the blood-brain barrier, a protective layer that usually prevents harmful substances from reaching the brain. Once inside, the virus can cause inflammation and damage to blood vessels, leading to a range of neurological symptoms.
What the Researchers Found
The study revealed that a significant number of COVID-19 patients, even those who only had mild respiratory symptoms, experienced neurological problems. These issues ranged from mild symptoms like brain fog and difficulty concentrating to more severe problems such as seizures, hallucinations, and, in some cases, suicidal thoughts. What’s alarming is that these symptoms often lasted long after the respiratory symptoms had resolved, showing that the virus’s impact on the brain could persist for months.
Follow-up studies in Germany and the United Kingdom found that between 20% and 70% of COVID-19 patients experienced neurological symptoms that continued for weeks or even months after recovering from the virus. This shows that COVID-19 may have lasting effects on the brain, especially in younger people who may not have had severe respiratory issues.
Implications for COVID-19 Survivors
These findings have significant implications for people recovering from COVID-19. Many survivors, especially those who had more severe infections, might need long-term medical care to manage their neurological symptoms. Doctors are now being advised to monitor COVID-19 patients for any signs of brain-related problems, even if their respiratory symptoms have improved. This could involve regular check-ups to assess cognitive function or mental health.
Some treatments are being explored to help manage these symptoms. Anti-inflammatory drugs may help reduce brain inflammation, and therapy could be useful for patients struggling with anxiety, depression, or cognitive difficulties.
What’s Next in Research?
The research into how COVID-19 affects the brain is still in its early stages. Scientists are continuing to study whether the brain can fully recover from the damage caused by the virus and what treatments are most effective for those experiencing long-term neurological symptoms. Future research will focus on developing therapies that can protect the brain and reduce the harmful effects of the virus.
This work is crucial because it could help millions of COVID-19 survivors who are struggling with brain-related issues. As more is understood about how the virus affects the brain, doctors will be better equipped to treat patients and prevent long-term damage.
Citation: Boldrini, M., Canoll, P. D., & Klein, R. S. (2021). How COVID-19 Affects the Brain. JAMA Psychiatry, 78(6). https://doi.org/10.1001/jamapsychiatry.2021.0500