PR96675

VIENNA, June 25, 2022 /PRNewswire=KYODO JBN/ --

COVID-19 positive outpatients are at an increased risk of neurodegenerative

disorders compared with individuals who tested negative for the virus, a new

study presented today at the 8th European Academy of Neurology (EAN) Congress

has shown.

The study, which analysed the health records of over half of the Danish

population, found that those who had tested positive for COVID-19 were at an

increased risk of Alzheimer's disease, Parkinson's disease, and ischaemic

stroke.

Out of the 919,731 individuals that tested for COVID-19 within the study,

researchers found that the 43,375 people who tested positive had a 3.5 times

increased risk of being diagnosed with Alzheimer's disease, 2.6 times with

Parkinson's disease, 2.7 times with ischaemic stroke and a 4.8 times increased

with intracerebral haemorrhage. While neuroinflammation may contribute to an

accelerated development of neurodegenerative disorders, the authors highlighted

implications of the scientific focus on long-term sequelae after COVID-19.

The study analysed Danish in- and outpatients between February 2020 and

November 2021, as well as influenza patients from the corresponding

pre-pandemic period. Researchers used statistical techniques to calculate

relative risk, and results were stratified for hospitalisation status, age,

sex, and comorbidities.

Dr Pardis Zarifkar, lead author from the Department of Neurology,

Rigshospitalet, Copenhagen, Denmark, explained, "More than two years after the

onset of the COVID-19 pandemic, the precise nature and evolution of the effects

of COVID-19 on neurological disorders remained uncharacterised. Previous

studies have established an association with neurological syndromes, but until

now it is unknown whether COVID-19 also influences the incidence of specific

neurological diseases and whether it differs from other respiratory infections".

The increased risk of most neurological diseases was, however, no higher in

COVID-19 positive patients than in people who had been diagnosed with influenza

or other respiratory illnesses. COVID-19 patients did have a 1.7 times

increased risk of ischaemic stroke in comparison to influenza and bacterial

pneumonia in patients over 80 years of age.

The frequency of other neurodegenerative illnesses such as multiple sclerosis,

myasthenia gravis, Guillain-Barré syndrome and narcolepsy did not increase

after COVID-19, influenza, or pneumonia.

Dr Pardis Zarifkar added, "These findings will inform our understanding of the

long-term effect of COVID-19 on the body and the role that infections play in

neurodegenerative diseases and stroke."

SOURCE : EAN Congress 2022