- UOC researchers have reviewed scientific studies on the effect of SARS-CoV-2 on the central nervous system
- They found that delirium is a key symptom to look out for, especially in older Covid-19 patients
- According to the research team, the virus has the ability to directly invade the brain
Delirium, accompanied by high fever, is a new potential early Covid-19 symptom to watch out for – particularly in elderly patients – researchers from the Universitat Oberta de Catalunya (UOC), Spain, announced.
"Delirium is a state of confusion in which the person feels out of touch with reality, as if they are dreaming," UOC researcher Javier Correa, who carried out this study at the University of Bordeaux (France), explained in a UOC release.
Correa and his colleague Diego Redolar Ripoll’s scientific research review was published in the open-access Journal of Clinical Immunology and Immunotherapy.
The team added that, together with the loss of the senses of taste and smell and headaches that occur in the days prior to the manifestation of coughing and breathing difficulties, some patients also develop delirium.
"We need to be on the alert, particularly in an epidemiological situation like this, because an individual presenting certain signs of confusion may be an indication of infection," said Correa.
Headaches, delirium, psychotic episodes
Correa and Ripoll looked at the effects of Covid-19 in relation to the central nervous system (CNS), and discovered that, apart from initial findings early on in the pandemic that focused on the damage caused to the lungs and other organs, more recent studies have been pointing to the effects it can have on the CNS.
They wrote that these effects result in neurocognitive alterations, including headaches and delirium, as well as psychotic episodes.
How does this happen?
"The main hypotheses which explain how the coronavirus SARS-CoV-2 affects the brain point to three possible causes: hypoxia or neuronal oxygen deficiency, inflammation of brain tissue due to cytokine storm; and the fact that the virus has the ability to cross the blood-brain barrier to directly invade the brain," explained Correa.
Any of these three factors, he commented, has the potential to cause delirium.
Correa also explained that hypoxia-related brain damage has been found in autopsies on people who who died from Covid-19, where researchers have been able to separate the virus from the cerebral tissue.
Earlier research on Covid-19 and delirium
Health24 reported on a study published in the Nature Public Health Emergency Collection earlier this year that found that "delirium is not inevitable; rather, it is preventable,” the Italian authors wrote, adding:
"Delirium prevention programmes are even more crucial in the era of Covid-19 and cannot be allowed to wither despite the challenges of integrating delirium prevention with Covid-19 care."
In a more recent study, published in Seizure: European Journal of Epilepsy, altered mental status, including delirium, coma or confusion were found in 61.7% of patients studied.
The lead author of the study stressed that the findings demonstrate a need for EEG (electroencephalogram) on a wider range of Covid-19 patients, as well as other types of brain imaging, such as MRI or CT scans, that will give doctors a closer look at the frontal lobe of patients, as they found that "half of status epilepticus and focal slowing originated in the frontal lobes".
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