Spectrum of EEG Abnormalities in COVID-19 Patients

Purpose: Neurologic involvement is commonly reported in coronavirus disease (COVID-19) patients. The published literature regarding the COVID-19–related neurophysiological findings, including the EEG findings, is still quite limited. The objective of this study was to evaluate the EEG findings in patients with a COVID-19 infection and look for a possible correlations and prognosis. Methods: This is an inpatient hospital-based retrospective observational study. All admitted COVID-19 patients undergoing an EEG study between January 1, 2020 and June 30, 2021 were included in this study. EEG was ordered by the primary intensive care physician or a neurologist taking part in the clinical care of patients. Results: Sixty-six EEG studies in 57 patients were included. Mean age was 62.2 ± 16.3 years with male predominance (65%). Encephalopathy (70%) was the most common indication for an EEG. Background EEG abnormalities were seen in most of the patients (92.4%) with severe abnormalities correlating with the prognosis of the patient. Epileptiform discharges were only seen in 7.5% of the EEGs, with majority of the discharges arising from the frontal region. Mortality reported was high (47%). Conclusions: Nonspecific diffuse background EEG abnormalities are commonly seen in COVID-19 patients. Epileptiform discharges are less common but mostly originate from frontal region. Most of these patients also had an abnormal neuroimaging. The significance of this peculiar finding needs further research. Significance: Nonspecific background EEG changes are common in COVID-19 patients. Among epileptiform discharges, focal epileptiform discharges arising from the frontal region were common, usually associated with an abnormal neuroimaging.