The Adaptive Role of Entorhinal Cortical Thickness in Post-COVID 19 Cognitive Impairment.

Introduction: Only limited information is still available concerning cognitive dysfunctions and cortical thickness in individuals who recovered from mild COVID-19 infections and did not require hospitalization. Our aim was to evaluate if the highly adaptive potential of cortical thickness might play a critical role in COVID-19-related cognitive disorder in a compensatory manner. Methods: Fifteen individuals with no history of medical, neurological, or psychiatric disease and with positive COVID-19 test results, and sixteen healthy age and education-matched healthy controls identified from the official hospital health system were evaluated in terms of cognitive scores using Alzheimer Disease's Assessment Scale-cognitive subscale (ADAS-Cog) and brain MRI cortical thickness measurements using FreeSurfer, Version 7.4.0. Results: An increased cortical thickness in the right entorhinal cortex (EC) and impaired cognition (increased ADAS score) were observed in the post-COVID 19 group as compared to the controls confirmed by the student's t test (respectively, p=0.006, p<0.001).The apparent correlation observed between cognitive impairment and increased entorhinal cortical thickness in our COVID-19 patients might suggest a continuum pathophysiology between healthy and COVID-19 affected brains that was not evident in previous COVID-19 cases with cognitive impairment. Conclusion: Our findings of increased entorhinal cortical thickness, together with impaired cognitive scores, may indicate a flexible role of EC thickness in compensatory mechanisms of cognition.