Brains Under Stress: Unravelling the Effects of the COVID-19 Pandemic on Brain Ageing

Abstract

The impact of SARS-CoV-2 and the COVID-19 pandemic on cognitive and mental health is recognised, yet specific effects on brain health remain understudied. We investigated the pandemics impact on brain ageing using longitudinal neuroimaging data from the UK Biobank. Brain age prediction models were trained from hundreds of multi-modal imaging features using a cohort of 15,334 healthy participants. These models were applied to an independent cohort of 1,336 participants with two MRI scans: either both before the pandemic (Controls) or one before and one after the pandemic onset (Pandemic group). Our findings reveal that, even with matched brain age gaps initially, the pandemic significantly accelerated brain ageing. The Pandemic group showed on average 11-month higher deviation of predicted brain age vs. chronological age (brain age gap) at the second time point compared with controls. Accelerated brain ageing was more pronounced in males and those from deprived socio-demographic backgrounds, with average increases of 3.3 and 7 months, respectively. These deviations existed regardless of SARS-CoV-2 infection. However, accelerated brain ageing correlated with reduced cognitive performance only in COVID-infected participants. Our study highlights the pandemics significant impact on brain health, beyond direct infection effects, emphasising the need to consider broader social and health inequalities.