Chronic neurological diseases and COVID-19: Associations and considerations

So many months after the start of the COVID-19 pandemic, scientists are still studying what the disease is capable of. Doctors already know a lot about what the condition does to the lungs, kidneys, and gastrointestinal tract. What about the brain? More and more detailed reports of brain diseases occur in people with relatively mild respiratory infections, critical conditions, and those in the recovery phase. While COVID-19 is still primarily a respiratory illness, many other diseases accompany it, including thromboembolism in the central nervous system. The occurrence of neurological symptoms such as anosmia, agenesis, and headache in most patients indicates that the virus invades the brain. This indication is supported by acute stroke-related disorders and decreased or altered consciousness in some coronavirus disease patients. 

Moreover, many recent studies show that viral RNA is found in the brain and cerebrospinal fluid. All these effects of a new coronavirus on a person’s brain and nervous system can cause long-term damage, even more so if a person has already suffered from neuralgic diseases before becoming infected. Scientists around the world say chronic neurological problems double the danger of COVID-19. However, scientists need more data on what happens to the nervous system of people with the coronavirus before making final predictions. 

How does the coronavirus attack the brain?

The coronavirus can affect the nervous system in different ways, and this is not only about the loss of taste and smell.

After coronavirus disease, patients often have problems with the central nervous system. Several cases of encephalitis (inflammation of the brain), as well as Guillain-Barré syndrome, have already been described: the patient’s immune system begins to attack its nerve cells, which leads to muscle weakness, and in severe cases, to paralysis.

In addition, a person with chronic cerebral vascular insufficiency with coronavirus has an increased risk of developing dementia, which grows more slowly without it. Also, after an illness, chronic neurological disorders may occur, accompanied by drowsiness, apathy, convulsions, or loss of consciousness. The cause lies in the insufficient supply of oxygen to the brain due to pulmonary insufficiency.

Specialists also pay attention to diseases of the spinal cord due to an infection. So, in elderly patients, due to coronavirus, Alzheimer’s or Parkinson’s disease is exacerbated.

According to preliminary data, coronavirus can provoke blood clots in patients as a side effect of inflammation. As a result, this leads to a critical violation of cerebral circulation, affecting the brain’s functioning.

Basically, neurological disorders are observed in patients with a severe stage of COVID-19. In such cases, neurological symptoms may remain in patients after a seemingly complete recovery from the coronavirus.

With coronavirus infection, the peripheral nervous system often suffers, and young people are also at risk. Als o at risk are people with chronic neurological diseases who receive immune-suppressing therapy.

Neurologists recommend following the doctor’s instructions on the primary diagnosis if, nevertheless, a person with neurological diseases contracted the coronavirus.

Why are neurological diseases progressing with COVID-19 dangerous?

The most serious diseases that can complicate the acute period of COVID-19, as well as be considered as its consequence, are cerebral stroke (ischemic strokes are more common, less often hemorrhagic), infectious diseases of the central nervous system (meningitis, meningoencephalitis), and autoimmune lesions (in particular the syndrome Guillain-Barre). The development of these complications aggravates the course of the coronavirus infection itself and poses an additional threat to the restoration of neurological functions and even the patient’s life.

The development of ischemic or hemorrhagic strokes in coronavirus disease is facilitated by the patient’s existing risk factors: arterial hypertension, atherosclerosis, diabetes mellitus, heart disease, lipid spectrum disorders, etc., that the stroke developed during the latent phase of infection. In general, coronavirus strokes occur due to endothelial dysfunction and systemic inflammatory response, which contribute to the occurrence of disseminated intravascular coagulation, a shift in hemostasis to a procoagulant state (characterized by increased blood clotting), and the occurrence of thrombosis and hemorrhages.

Other complications of COVID-19 are infectious processes: meningitis and meningoencephalitis, which also aggravate the course of the underlying disease and require specific therapy.

The SARS-CoV-2 virus can also cause damage to the peripheral nervous system.

Do people with chronic neurological diseases take COVID-19 harder? 

Today, there is no evidence that, for example, Parkinson’s disease or multiple sclerosis worsens the course of COVID-19. The severity of the disease is most likely also associated with the characteristics of the individual immune response and the patient’s risk factors. Let’s say a person has arterial hypertension, diabetes mellitus, overweight. These factors can already seriously complicate the course of coronavirus infection. At the same time, there are cases when patients with neurological diseases suffered from COVID-19 in an asymptomatic and mild form. The patient may have Parkinson’s disease, but he has good immunity, and the infection is relatively easy. In general, it is crucial to follow up with patients with neurological conditions who have suffered from coronavirus disease to understand the potential for delayed nervous system effects of this infection.

Coronavirus infection can be devastating to the brain. This statement is reported by the journal Nature concerning specialists from the University of Liverpool, University College London, Yale University, and the Icon School of Medicine. According to them, in 62% of patients who experienced neurological and psychiatric complications, the blood supply to the brain was damaged. At the same time, 31% had confusion and prolonged unconsciousness. Chronic neurological diseases of any form – dementia, Alzheimer’s disease, migraine, brain, and spinal cord or central nervous system lesions – double the danger of COVID-19.