Anxiety, depression may indicate COVID-19 impact on central nervous system, brain

COVID-19 comes with many symptoms. The most common ones that people look out for are sore throat, fever and breathing issues. But experts have seen that new symptoms keep coming up at regular intervals. Rashes and muscle aches, headache, altered mental status, acute cerebrovascular disease and epilepsy are fast becoming common symptoms of COVID-19 patients. In fact, some time back, a study at Istanbul University-Cerrahpasa showed that nearly 50 per cent of all COVID-19 patients, who were in the intensive care unit (ICU), had brain abnormalities on MRI scans. This was published in Radiology. It is now proven that this disease affects the central nervous system.

According to a new study at the University of Cincinnati in the US, depressed mood or anxiety exhibited in COVID -19 patients may possibly be a sign that the virus affects the central nervous system. The findings, published in the journal The Laryngoscope, reveals that these two psychological symptoms were most closely associated with a loss of smell and taste rather than the more severe indicators of the novel coronavirus such as shortness of breath, cough or fever. Researchers say that the unexpected results that the potentially least worrisome symptoms of COVID-19 may be causing the greatest degree of psychological distress could potentially reveal something about the disease.

Loss of smell and taste accompanied by depression and anxiety

For the study, the research team conducted a prospective, cross-sectional telephone questionnaire study, which examined characteristics and symptoms of 114 patients who were diagnosed with COVID-19 over a six-week period at Kantonsspital Aarau in Aarau, Switzerland. The severity of the loss of smell or taste, nasal obstruction, excessive mucus production, fever, cough and shortness of breath during COVID-19 were assessed. At the time of enrollment in the study, when participants were experiencing COVID-19, 47.4 per cent of participants reported at least several days of depressed mood per week while 21.1 per cent reported depressed mood nearly every day. In terms of severity, 44.7 per cent of participants reported expressing mild anxiety while 10.5 per cent reported severe anxiety.

Virus may enter central nervous system via the olfactory tract

According to researchers, these findings suggest the possibility that psychological distress in the form of depressed mood or anxiety may reflect the penetration of SARS-CoV-2, the virus that causes COVID-19, into the central nervous system. Researchers have long thought that the olfactory tract may be the primary way that coronaviruses enter the central nervous system. Studies using mouse models of that virus have shown that the olfactory tract, or the pathway for communication of odours from the nose to the brain, was a gateway into the central nervous system and infection of the brain.

Indication of infection of olfactory neurons

According to researchers, these symptoms of psychological distress, such as depressed mood and anxiety are central nervous system symptoms if they are associated only with how diminished your sense of smell is. This may indicate that the virus is infecting olfactory neurons, decreasing the sense of smell, and then using the olfactory tract to enter the central nervous symptom.