Abstract, published in Epilepsia
Objective: There is evidence for central nervous system complications of COVID-19 infection, including encephalopathy (any brain disease that adversely affects brain function and/or structure). Encephalopathy caused by or arising from seizures, especially nonconvulsive seizures (NCS), often requires EEG monitoring for diagnosis, but the prevalence of seizures and other EEG abnormalities among COVID-19-infected patients is unknown. We thus sought to quantify this prevalence.
Methods: Medical records and EEG studies of patients hospitalized with confirmed COVID-19 infections over a 2-month period at a single US academic health system (four hospitals) were reviewed to describe the distribution of EEG findings including epileptiform abnormalities (seizures, periodic discharges, or nonperiodic epileptiform discharges).
Results: Of 111 patients monitored, most were male (71%), middle-aged or older (average age 64 years), admitted to an intensive care unit (ICU; 77%), and comatose (70%). Excluding 11 patients monitored after cardiac arrest, the most frequent EEG finding was moderate generalized slowing (57%), but epileptiform findings were observed in 30% and seizures in 7% (4% with NCS). Three patients with EEG seizures did not have epilepsy or evidence of acute or remote brain injury, although all had clinical seizures prior to EEG. Only having epilepsy or seizure(s) prior to EEG was independently associated with epileptiform EEG findings.
Significance: This study supports growing evidence that COVID-19 can affect the central nervous system, although seizures are unlikely a common cause of encephalopathy. Seizures and epileptiform activity on EEG did not occur often and having a history of epilepsy or seizure(s) prior to EEG testing was predictive of epileptiform findings. This has important implications for triaging EEG testing in this population.