The following is a summary of “Altered intrinsic brain activity and functional connectivity in COVID-19 hospitalized patients at 6-month Follow-up,” published in the August 2023 issue of Infectious Diseases by Li et al.

In the retrospective study, researchers aimed to explore the long-term changes in local and regional brain activity and the connection and interaction between different brain regions in patients who have recovered from COVID-19. The patients who recovered from SARS-CoV-2 infection in the short run and the long-term effects of COVID-19 on the brain remain explored. Functional MRI (fMRI) can help to examine people experiencing long COVID symptoms.

The study enrolled 35 people who had been hospitalized due to COVID-19 before. Besides this, 36 healthy people who didn’t have COVID-19 were also enrolled. Further, their particular regional brain activity was assessed using the amplitude of low-frequency fluctuation (ALFF) and seed-based functional connectivity (FC) and compared the results. They analyzed the impact of disruptions in specific brain areas on parts of the brain’s functioning. At last, they performed Spearman correlation analyses to find the connectivity between brain function changes and clinical variables.

At 6- months of follow-up, only six people out of 35 had fewer neuro symptoms (7.14%) compared to when they were hospitalized due to COVID-19 (21/35, 60%). Both groups’ brain activity was compared. People who recovered from COVID-19 had some parts of the brain that were more active (higher ALFF in the right precuneus, middle temporal gyrus, middle and inferior occipital gyrus). In comparison, others were less active(lower ALFF in the right middle frontal gyrus and bilateral inferior temporal gyrus). Additionally, they observed some abnormal activity in some regions of the brain. High FC was observed between the right middle occipital gyrus and the left inferior occipital gyrus. On the other hand, low FC was observed between the right inferior occipital gyrus and right inferior temporal gyrus/bilateral fusiform gyrus and between the right middle frontal gyrus and right middle frontal gyrus/ supplementary motor cortex/ precuneus. Furthermore, the irregular ALFF and FC were connected to clinical factors.

The study concluded that COVID-19 neurological symptoms can resolve naturally with time. Recovered patients showed changes in brain function, particularly in frontal, temporal, and occipital lobes, with altered interactions between nearby brain regions.

Source: bmcinfectdis.biomedcentral.com/articles/10.1186/s12879-023-08331-8