Study: Covid less likely to cause brain complications than vaccination

LONDON: According to a study conducted by the University of Oxford in Great Britain, Covid-19 is more likely to cause very rare neurological diseases than vaccination with the protective agents AstraZeneca or Pfizer.

Covid is more likely to cause brain complications than vaccination

There have been reports of rare neurological complications related to SARS-CoV-2 infection and the Oxford-AstraZeneca or Pfizer-BioNTech Covid-19 vaccines.

The study, published Monday in the journal Nature Medicine, analyzed the anonymized medical records of more than 32 million people across England.

The researchers assessed the risk of developing neurological complications within 28 days of an initial dose of the AstraZeneca vaccine, known in India as Covishield, or a prophylactic Pfizer, or within 28 days of testing positive for Covid-19.

They found an increased risk of rare neurological diseases, Guillain-Barré syndrome and Bell’s palsy after a first dose of AstraZeneca vaccine and an increased risk of hemorrhagic stroke after the first dose of Pfizer, albeit a low one.

However, according to the researchers, having Covid-19 was associated with a higher risk of developing neurological complications than having any vaccine.

“This analysis provides important information about neurodegenerative diseases that could be associated with vaccination or infection with Covid-19,” said Professor Carol Copeland from the University of Nottingham in the UK and one of the researchers involved in the study.

Overall, the results of this study show that the risks of hospitalization due to nervous system complications associated with Covid-19 infection are greater than the risks associated with Covid-19 vaccines.

The researchers found different risks for different types of neurodegenerative diseases depending on which vaccine people got.

However, these were well below the risks associated with a positive Covid-19 PCR test.

For example, we estimate an additional 145 cases of Guillain-Barré syndrome per 10 million people in the 28 days after testing positive for SARS-CoV-2, compared to 38 per 10 million for those who received the AstraZeneca vaccine, said Martina Patton of the University of Oxford and co-lead author of the study. studying.

The researchers found that early clinical trials of vaccines were not large enough to detect very rare neurological adverse events — those affecting less than 1 in 10,000 people.

The latest study, they said, did just that by looking at real-world data from more than 32 million health records in England.

A so-called “autonomous case series (SCCS)” design was used in the study.

SCSS compares how often adverse events — in this case, neurological complications — occur in different time periods.

The authors note several limitations of the study, including that only the risks associated with the first dose of the vaccine were examined.

Data on outcomes after the second doses were limited at the time of this study as the UK vaccination program is still ongoing.

The researchers were also unable to switch between species due to the way medical records were encoded Guillain-Barré syndromes Distinguish.