October 8, 2024

expert reaction to study on MRI scans and brain damage/long-lasting Covid-19 symptoms

A study published in Brain looks at MRI scans and brain damage associated with long lasting Covid-19 symptoms. 

Prof Paul Mullins, Professor in Neuroimaging, University of Bangor, said:

Does the press release accurately reflect the science?

“The press release is a fairly good reflection of the science, although it does over sell the ability of the data to explain long COVID.

Is this good quality research?  Are the conclusions backed up by solid data?

“This is a piece of research using sophisticated imaging techniques to provide data not available from clinical imaging scanners. The imaging is good and shows that there are differences in the brain stem of patients who were hospitalised with COVID-19, with greater changes in patients with more severe COVID.

How does this work fit with the existing evidence?

“This fits with some earlier work showing a change in the specific measure, QSM, from this group, and also other work showing long term changes on such sophisticated brain scanning. This finding adds to our knowledge about which regions of the brain COVID impacts, showing change in those regions involved in respiration and other autonomic functions.

Have the authors accounted for confounders?  Are there important limitations to be aware of?

“The authors have attempted to account for most confounders, however, there is some limitation with the small number of patients scanned, and the use of a single time point. This is understandable considering that the study took place during the first waves of the pandemic with associated lockdowns and complications. 

What are the implications in the real world?  Is there any overspeculation? 

“This data shows that there may be an increase in iron deposition within the brain stem regions – which likely reflects inflammation – however the technique is not able to determine if this is ongoing inflammation, or the result of past inflammations, so it is likely too early for the authors to conclude that persistent inflammation is present in the brain stem, and that this is the cause of long covid, from this data set alone.

Does this study conclusively prove what causes long COVID?

“While this study does not conclusively prove the causes of long COVID, it does point a finger at one possible suspect for some of the symptoms experienced.

What does this tell us about how long COVID should be treated now and in the future?

“It is not clear that this shows much in the way of possible treatments for long COVID once it has occurred, but it perhaps does point to the need to reduce inflammatory responses during initial COVID infection and response, as lower inflammation was related to smaller changes in the QSM measure used.”

‘7-Tesla quantitative susceptibility mapping in COVID-19: brainstem effects and outcome associations.’ by Catarina Rua et al. was published in Brain at 0:01 UK time on Tuesday 08 October 2024.

DOI: 10.1093/brain/awae215

Declared interests

Prof Paul Mullins “is a professor in neuroimaging at Bangor University and the Director of the Masters in Neuroimaging degree at Bangor University, has received European funding for the use of Neuroimaging in ageing and dementia studies in the past, and has received UKRI funding for research into the use of nutraceuticals for brain health. Professor Mullins researches brain metabolism and physiology, and the brain’s response to environmental stresses, including hypoxia as might be experienced during server acute COVID-19 infections.”