Magnetic resonance imaging (MRI) study of changes in brain structure and function associated with SARS-CoV2 infection

Study code
DAA172

Lead researcher
Professor Ed Bullmore

Study type
Data only

Institution or company
University of Cambridge

Researcher type
Academic-led

Speciality area
COVID, Neurological Disorders

Summary

Brain complications can affect up to 20-30% of patients who have been hospitalised with severe COVID-19 due to SARS-CoV2 infection. There is growing evidence that COVID-19 is linked to ongoing impairment in people’s thinking ability (cognition), but the brain mechanisms that cause this cognitive deficit are not well understood.

Characterising these mechanisms would help to direct the use of current therapies and to identify potential targets for new therapeutics in the future. In the current project, we wish to determine if cognitive problems are linked to changes or damage in the brain. We will do this by looking at a broad range of magnetic resonance imaging (MRI) data and determine if these are related to changes in blood proteins and results from various cognitive tests. In addition, we want to determine whether there are specific changes in different brain areas (including in the cortex, white matter tracts, and cerebrovascular system). We will also include other clinical data, such as past medical history and findings from hospital records, questionnaires related to participants’ physical and mental health. Our assumption is that certain areas in the brain will have been negatively affected by the immune response to the participants’ SARS-CoV2 infection.

Patient benefit

The results from this study will help us to understand the brain mechanisms of cognitive impairment; a common and potentially disabling consequence of SARS-CoV2 infection. This greater understanding will be of immediate benefit in guiding the most effective use of existing treatments and will be of longer-term benefit by supporting the development of novel treatments for post-COVID cognitive and psychological symptoms.

Research publication

Wood, G.K., Sargent, B.F., Ahmad, ZUA. et al. Post-hospitalisation COVID-19 cognitive deficits at one year are global and associated with elevated brain injury markers and grey matter volume reduction. Nat Med (2024). 

https://doi.org/10.1038/s41591-024-03309-8

 

Main findings

The spectrum, pathophysiology, and recovery trajectory of persistent post-COVID-19 cognitive deficits are unknown, limiting our ability to develop prevention and treatment strategies. We report the one-year cognitive, serum biomarker, and neuroimaging findings from a prospective, national study of cognition in 351 COVID-19 patients who had required hospitalisation, compared to 2,927 normative matched controls. Cognitive deficits were global and associated with elevated brain injury markers, and reduced anterior cingulate cortex volume one year after COVID-19. The severity of the initial infective insult, post-acute psychiatric symptoms, and a history of encephalopathy were associated with greatest deficits. There was strong concordance between subjective and objective cognitive deficits. Longitudinal follow-up in 106 patients demonstrated a trend toward recovery. Together, these findings support the hypothesis that brain injury in moderate to severe COVID-19 may be immune-mediated, and should guide the development of therapeutic strategies.