COVID-19 Pandemic Impacts on STRESS, PTSD, and Prefrontal Cortical Thickness in Pre-Pandemic Trauma Survivors

<b>Background/Objectives</b>: The COVID-19 pandemic increased psychiatric symptoms in patients with pre-pandemic mental health conditions. However, the effects of pandemic on the brain, stress, and mental illness remain largely conjectural. Our objective was to examine how the pandemic affected prefrontal cortical thicknesses (CTs), stress, and PTSD symptoms in people with pre-pandemic trauma histories. <b>Methods</b>: Fifty-one survivors from a pre-pandemic trauma study who had completed a pre-pandemic PTSD Checklist-5 (PCL) to assess PTSD symptoms and a sMRI scan to measure prefrontal CTs were re-recruited after the pandemic. They subsequently completed the COVID Stress Scale (CSS) to assess stress, the Clinician Administered PTSD Scale-5 (CAPS) to diagnose PTSD, and a second sMRI scan. COVID-19 infection was self-reported. Associations between stress and symptom assessments and post-pandemic CTs, differences in CTs in PTSD vs. non-PTSD groups, and changes in pre- to post-pandemic CTs were examined. <b>Results</b>: Pre-pandemic PCL scores were positively associated with CSS scores which, in turn, were higher in the PTSD group. Thicker IFG-opercularis CTs were associated with COVID-19 infection. Post-pandemic rMFG and IFG-orbitalis CTs were positively associated with CAPS scores. rACC CTs were negatively associated with CSS scores. Pre- to post-pandemic rMFG and frontal pole CTs thickened in the PTSD group but thinned in the non-PTSD group, whereas rACC CTs thinned in the PTSD group but thickened in the non-PTSD group. <b>Conclusions</b>: These findings provide novel evidence that the COVID-19 pandemic had diverse effects involving prefrontal cortex structure, stress, and PTSD symptoms in subjects with pre-pandemic trauma history and suggest that treatments are needed to counter these diverse effects.