Brain long distance functional connectivity mediates the relationship between fatigue and PTSD after COVID-19 infection.

Motivation: Brain network alterations in acute phase of coronavirus disease 2019 patients (acute-COVID) with fatigue has not yet been elucidated. Goal(s): Our goal was to determine the characteristics of alterations in brain network and the neurobiological mechanisms in acute-COVID patients with fatigue. Approach: We utilized graph theory analysis to assess brain network alterations in COVID-19 patients. Results: Results demonstrated the abnormalities in brain network in acute-COVID patients with fatigue, involing left insular gyrus and right inferior frontal gyrus. Morever, the normalized characteristic path length of global brain in acute phase of COVID-19 could predict the development of chronic symptoms. Impact: Our functional MRI findings highlight abnormal brain network metrics in acute phase COVID-19 patients with fatigue, offering valuable neuroimaging marker for early clinical intervention in long-COVID patients.