Cognitive and behaviorial features of a cohort of patients in COVID-19 post-acute phase

Background and aims: Our study aimed to assess EEG findings and their clinical and neuropsychological correlates in patients with recent COVID-19. Methods: We enrolled 55 adult patients with recent COVID-19, good recovery and objective and/or selfreported cognitive disturbances, observed at follow-up neurological evaluation (2 months after discharge). Sameday basal EEG and neuropsychological testing battery were performed. EEG were assessed for background activity, individual alpha frequency (IAF), presence/location of focal slowing, epileptiform abnormalities and seizures. Correlations with neuropsychological and clinical variables were assessed using linear/logistic regression. Results: We evaluated 55 patients (70.9% males, mean age 60.5±13.3 years);13/55 (23.6%) had needed ventilatory support (12 NIV, one intubation). Mean adjusted Montreal Cognitive Assessment (MoCA) score was 21.3±2.8. Modest EEG background-activity alteration was observed in 5/55 (9.1%) patients. Prevailing fronto-temporal focal slowwave activity (SWA) was observed in 6/55 (10.9%) patients. Brief (<5 sec) anterior theta/alpha activity sequences were recorded in 10/55 (18.2%) subjects. No epileptiform/seizure discharges were recorded. 41/55 (74.5%) patients had experienced mild neurological symptoms during acutephase COVID-19. Only confusion/disorientation was associated with EEG parameters, particularly with anterior theta/alpha activity. IAF did not correlate with acute-phase respiratory severity scores or neuropsychological findings. Presence of anterior theta-alpha activity was associated with lower executive-function scores at frontal assessment battery and symbol-digit modalities test. Executive-function impairment was not associated with background-activity alteration or SWA. Conclusion: EEG alterations after COVID-19 might be independent of acute infection severity and suggest a link with ongoing neuro-psychiatric symptoms. Further followup data is needed to confirm the reversibility and/or evolution of our findings.