Covid-19 and the brain: neurological symptoms experienced in even mild coronavirus cases.

The list of neurological symptoms suffered in the wake of Covid-19 infection is growing.

Until recently, the focus was largely on respiratory damage caused by the virus.

But more and more evidence is now emerging of neurological and psychiatric symptoms that can develop after contracting it, these ongoing symptoms are described as ‘long covid’.

Research cited in a new report in the scientific journal, Nature [1], describes:

Altered mental states

A UK-wide study of 125 Covid-19 patients [2] revealed 31% experienced altered mental states (encephalopathy), such as prolonged unconsciousness or confusion.

More widely, delirium is being reported as an effect of infection, with patients becoming agitated, confused and disorientated. [3]

Other symptoms included:

• Executive dysfunction
• Memory loss
• Loss of alertness
• Poor judgement
• Emotional irregularity
• Impaired perception
• Psychosis

In one of the first cases of its type, a woman in her 50s with no psychiatric history developed psychosis after contracting Covid-19. [4] She was ‘seeing’ lions and monkeys in her house and became disoriented and aggressive towards others.

In the UK-wide study [2], ten people with altered mental states developed psychosis.

  The neurological symptoms are only becoming scarier.   

- Alysson Muotri, University of California neuroscientist. [1] 

Stroke

Over 60% of the participants in the UK study [2] experienced damage to the brain’s blood supply, such as strokes and haemorrhages.

A research review in The Lancet [5] confirmed “unexpectedly” acute cerebrovascular disease was, indeed, emerging as a Covid-19 complication.

It pointed to cohort studies in which in 2–6% of patients hospitalised with COVID-19 also suffered a stroke.

A separate report [6] revealed haemorrhagic strokes have been seen in Covid-19 patients aged in their 50s to 80s in the UK while, in the USA, ischaemic strokes have been reported in people in their 30s and 40s.

Encephalitis

Some 6% of Covid-19 patients admitted to hospital with neurological problems are likely to develop encephalitis (inflammation of the brain), according to the UK study. [2]

Along with stroke, encephalitis was also one of the most common symptoms revealed in a study of 43 people with Covid-19 by neurology researchers at University College London (UCL). [4]

In some cases, it developed into acute disseminated encephalomyelitis, with symptoms resembling those of multiple sclerosis.

   This was the brain being hit as their main disease.   

- UCL neurologist, Michael Zandi . [1]

Peripheral nerve damage

Less commonly, peripheral nerve damage may occur following Covid-19 infection. [6] [7]

Symptoms may be similar to those of Guillain-Barre Syndrome, a very rare neurological disorder that mainly affects the hands, feet and limbs, causing weakness, numbness and pain.

Back to basics

Neuro OTs, like other health workers, will, no doubt, be aware of symptoms already having known links to Covid-19 infection [8], including:

• Fatigue
• Headache
• Loss of smell (anosmia)
• Loss of taste (dysgeusia)
• Post-traumatic stress disorder
• Anxiety
• Fear
• Depression
• Muscle weakness
• Neuropathy

But, in a new study [9], researchers warn they could find ‘no significant difference in the frequency of neurological symptoms’ between severe and non-severe Covid-19 cases.

‘Neurological symptoms are frequent in COVID-19. Care should be taken to identify them early.’ [9]

Researchers at the US’s Yale School of Medicine echoed the advice to ID symptoms as promptly as possible.

In a scoping review of the evidence [10], they also found stroke, impairment of consciousness, seizure, and encephalopathy among the shared symptoms.

‘Neurologic and cognitive assessment of individuals after recovery from COVID-19 will be crucial to…monitor for any long-term neurologic sequelae.’ [10]

Rapid response

The race to find a vaccine for Covid-19 is running parallel with another at present: the race to discover why, in some cases, the virus damages the brain.

There seem to be two schools of thought for now:

• That Covid-19 invades and infects the brain, via the olfactory system, disrupting the nerve cells, as other viruses can.
• That the immune system goes into overdrive in response to the virus, causing brain inflammation and other secondary disorders

Krysalis is tracking Covid-19 developments, particularly those linked to brain injury and how neuro occupational therapists can assist survivors to ensure that symptoms do not become chronic in nature or impact on performance and participation for longer than necessary. Check back for updates.

Related articles

Occupational Therapists lead an urgent global search for long-covid rehabilitation evidence

Keeping brain injury survivors safe during the easing of lockdown rules

BBC news. Long Covid: 'My fatigue was like nothing I've experienced before'

References

The Spectrum of Neurologic Disease in the Severe Acute Respiratory Syndrome Coronavirus 2 Pandemic Infection: Neurologists Move to the Frontlines, Pleasure, S. J. et al, Jama Neurology, April 2020

COVID-19 presenting as stroke, Avulaa, A. et al, Brain, Behaviour and Immunity, April 2020

Neurological and Radiographic Findings Associated With COVID-19 Infection in Children, Abdel-Mannan, O. et al, Jama Neurology, July 2020

[1] Marshall, M. “How COVID-19 can damage the brain,” Nature, September 2020.
[2] Varatharaj, A. et al. “Neurological and neuropsychiatric complications of COVID-19 in 153 patients: a UK-wide surveillance study,” The Lancet Neurology, June 2020.
[3] Kotfis, K. et al. “COVID-19: ICU delirium management during SARS-CoV-2 pandemic,” Critical Care, April 2020.
[4] Paterson, R. W. et al. “The emerging spectrum of COVID-19 neurology: clinical, radiological and laboratory findings,” Brain: []A Journal of Neurology, July 2020.
[5] Ellul, M. A. et al. “Neurological associations of COVID-19,” The Lancet Neurology, July 2020.
[6] Wilson, B. A. et al. “Neuropsychological Consequences of Covid-19,” Neuropsychological Rehabilitation, July 2020.
[7] Nanda, S. et al. “Covid-19 associated Guillain-Barre Syndrome: Contrasting tale of four patients from a tertiary care centre in India,” Science Direct, September 2020.
[8] Mishra, R. et al. “Neurological Anomalies Caused by SARS-CoV-2,” Frontiers in Immunology, September 2020.
[9] Makda A, et al. “The Frequency of Neurological Symptoms in COVID-19 Patients at a Tertiary Care Hospital in Pakistan,” Cureus, September 2020.
[10] Zubair, A. S. “Neuropathogenesis and Neurologic Manifestations of the Coronaviruses in the Age of Coronavirus Disease 2019: A Review,” Jama Neurology, May 2020.