Brain fog is one of the most common health complications that coronavirus patients experience post-recovery. Although it is not dangerous and potentially fatal like other side effects of the infection, it can still affect the quality of life significantly.
For instance, the majority of the people having the issue report an inability to concentrate or think clearly. As a result, it also affects their works or school performance. Sometimes, brain fog may even make it difficult to perform everyday tasks.
Although it has been identified as an associated health outcome of COVID-19, the primary cause for the complication is still unclear. Now, new research, which appears in the journal Cancer Cell, shows that the reason for brain fog may be inflammation.
More specifically, the scientists from the Memorial Sloan Kettering Cancer Center (MSK) in New York found particles of inflammation in the cerebrospinal fluid of eighteen cancer patients who also had coronavirus infection.
These patients had been hospitalized due to having severe symptoms of neurological damage while having the infection. To investigate more on the neurological impact, they then underwent a number of brain tests including electroencephalogram (EEG) monitoring, Magnetic Resonance Imaging (MRI), and Computerized Tomography (CT) scans.
Thirteen out of eighteen of the patients also had a spinal tap, which is a procedure done to get a sample of cerebrospinal fluid.
After examining all reports and test results, the scientists discovered that cytokines, which are the signaling molecules responsible for causing inflammation were present in the cerebrospinal fluid of the patients even weeks after getting infected and even after recovery.
Additionally, these patients were also compared to cancer patients who receive CAR T treatment. In this therapy, the cytokines are removed by immune cells but there are also a number of side effects including a delay in neurological functions.
Therefore, the patients getting CAR T as a treatment for cancer had issues similar to cancer patients with COVID-19.
Although the reports identified inflammatory particles in the cerebrospinal fluid, they did not find any SARS-CoV-2 viruses in it. Research conducted prior to the new study concluded that the virus itself caused neurological symptoms leading to associated effects after recovery.
While there is some evidence the SARS-CoV-2 virus can indeed affect the brain in severe forms of the infection, the new findings show that this is not always necessary. Inflammation alone can be the reason for neurological signs and post-recovery complications such as brain fog.
Another interesting finding of the research was that immune cells are able to enter the Central Nervous System (CNS) via the brain-blood barrier, unlike other cells. The presence of cytokines in the cerebrospinal fluid is sufficient evidence to support this theory.
Consequently, not only can these results add to the general understanding of the health outcomes of COVID-19 but may also help in learning more about how cancerous cells spread to the brain of a patient.
Further investigation in the future may then result in finding a way to prevent neurological effects of coronavirus such as brain fog or in keeping cancer from reaching the brain.