Impact of long‐COVID on the local and global efficiency of brain networks

Abstract

AbstractBackground and purposeSubjective cognitive complaints post‐COVID‐19, known as long‐COVID, have unclear effects on neural activity. This study explores the neural basis of these cognitive impairments by comparing resting‐state functional networks of long‐COVID individuals to a control group.MethodsForty‐two individuals with cognitive complaints persisting 24 weeks post COVID‐19 infection and 43 age‐, sex‐ and education‐matched healthy controls without a history of infection were studied using resting‐state functional MRI (rs‐fMRI) and the Uniform Data Set (UDS‐3) neurocognitive test battery (NCT). Neuropsychological scores were adjusted to the mean and grouped into seven cognitive composites. The rs‐fMRI data were partitioned into seven distinct functional neural networks—Salience/Ventral Attention, Dorsal Attention, Default, Frontoparietal, Visual, Somatomotor, and Limbic—and their efficiency, largest connected component, and modularity (Q) were studied.ResultsThe NCT scores yielded statistically significant differences in long‐COVID subjects compared to controls at attention, language, memory, executive, and global composites. We observed significant differences (p < .001) in the global and mean local efficiency of the Salience/Ventral Attention and Global networks, and to a lesser extent (p < .005 and p < .01) in the Default and Dorsal Attention networks.ConclusionsOur findings reveal significant group‐level differences in executive, attentional, language, and memory outcomes, alongside less efficient and organized connections among Salience/Ventral Attention and Global networks.