The COVID-19 Pandemic Is Associated With Accelerated Brain Aging

The COVID-19 pandemic is associated with accelerated brain aging, even among individuals who were not infected with SARS-CoV-2. These findings were published in Nature Communications.

Researchers used longitudinal neuroimaging data from the UK Biobank to examine the relationship between brain aging and the COVID-19 pandemic. They used pre-pandemic magnetic resonance images (MRIs) from 15,334 healthy adults, aged 45 years and older, to train gender-specific models that predict brain age based on gray and white matter. The models were applied to longitudinal MRI data from 996 participants, of whom the mean (SD) age was 58.8 (6.2), and 552 were women. Participants were divided into 2 groups: the pandemic group, consisting of 432 participants, had scans before and after March 2020, while the control group, with 564 participants, had 2 scans before March 2020.

The researchers observed no significant difference in brain age gap (BAG) between the pandemic and control groups in the first MRI scans. However, in the second scans, the rate of change in BAG (R_BAG) was significantly higher in the pandemic group compared with controls for both gray matter (d, 0.606; P <.0001) and white matter (d, 0.697; P <.0001).

To determine whether accelerated brain aging was linked to SARS-CoV-2 infection, the pandemic group was divided into 2 subgroups: those who had COVID-19 (n=134) and those who did not (n=298) before the second scan. The R_BAG was significantly higher in both the infection (d, gray matter: 0.65; white matter: 0.693) and no infection (d, gray matter: 0.518; white matter: 0.599) subgroups relative to controls, indicating that brain aging occurred independent of direct effects from COVID-19 infection.

Incorporating chronological age into the models showed accelerated brain aging in older adults, with each additional year corresponding to a 3-day acceleration in gray (P =.0027) and white matter aging (P =.002) for the control group. The pandemic cohort experienced a higher rate of BAG acceleration, with each additional year of age corresponding to a 7-day acceleration in gray matter aging (P =.0048) and an 8-day acceleration in white matter aging (P =.0005). However, the fastest BAG acceleration was observed among individuals who had COVID-19 prior to their second scan, with each additional year of age corresponding to a 9-day increase in gray matter aging (P =.004) and a 10-day increase in white matter aging (P =.0069).

Further, a significant gender interaction was observed for COVID-19-related gray matter aging (P =.036), with more accelerated aging among men.

The cognitive effects of accelerated brain aging were observed only in individuals who had COVID-19, manifesting as worse performance on the trail making test.

Study limitations include the use of only 2 time points, which prevented the exploration of potential reversibility.

“Our findings highlight the need to address health and socio-economic inequalities in addition to lifestyle factors to mitigate accelerated brain ageing,” the authors concluded.

Disclosures: Some study authors declared affiliations with biotech, pharmaceutical, and/or device companies. Please see the original reference for a full list of authors’ disclosures.