ELECTROPHYSIOLOGICAL CHANGES IN THE PARTICIPANTS OF THE LIQUIDATION OF THE CONSEQUENCES OF THE CHORNOBYL ACCIDENT AND THE MILITARY PERSONNEL OF THE UKRAINIAN DEFENSE FORCES RECOVERING FROM CORONAVIRUS DISEASE (COVID-19)
Authors:   State Institution «National Research Center for Radiation Medicine, Hematology and Oncology of the National Academy of Medical Sciences of Ukraine», Bazyka D. A. , Kuts K. V. ,   State Institution «National Research Center for Radiation Medicine, Hematology and Oncology of the National Academy of Medical Sciences of Ukraine», Perchuk I. V. ,   State Institution «National Research Center for Radiation Medicine, Hematology and Oncology of the National Academy of Medical Sciences of Ukraine», Kreinis G. Y. ,   State Institution «National Research Center for Radiation Medicine, Hematology and Oncology of the National Academy of Medical Sciences of Ukraine», Antipchuk K. Y. ,   State Institution «National Research Center for Radiation Medicine, Hematology and Oncology of the National Academy of Medical Sciences of Ukraine», Vasylenko Z. L. ,   State Institution «National Research Center for Radiation Medicine, Hematology and Oncology of the National Academy of Medical Sciences of Ukraine», Hryhorenko M. S. ,   State Institution «National Research Center for Radiation Medicine, Hematology and Oncology of the National Academy of Medical Sciences of Ukraine»
Published: December 2024

Objective: to conduct a clinical and neurophysiological study of Chornobyl clean-up workers and military personnel of the Armed Forces of Ukraine (AFU) with previous coronavirus disease (COVID-19) and individuals of the comparison groups to study the impact of long-term effects of ionizing radiation, psychoemotional stress and previous coronavirus infection on cerebral functioning.
Materials and methods. A prospective clinical study of Chornobyl clean-up workers and servicemen of the Armed Forces of Ukraine (AFU) who had coronavirus disease (COVID-19) and individuals of the comparison groups. The main group – 30 males participated in liquidating the consequences of the Chornobyl Nuclear Power Plant (ChNPP) accident with previously verified COVID-19 (Chornobyl clean-up workers). As a nosological control group (NCG), 24 men with verified chronic cerebrovascular disorder (CVD) not exposed to radiation sources, war-associated psychoemotional stress, and COVID-19 were examined in 2020–2022. Depending on the history of COVID-19, the AFU servicemen were divided into 2 subgroups: «COVID+» and «COVID-». The diagnosis of neuropsychiatric disorders was established according to ICD-10. Visual and spectral EEG analyses assessed cerebral functions in passive wakefulness (rsEEG).
Results. Chornobyl clean-up workers «COVID+» and NCG groups did not differ significantly in clinical neuropsychiatric features, except for a higher frequency of organic personality disorder (F07) in the group of the Chornobyl clean workers «COVID+» (p < 0.001). In the group of the Chornobyl clean workers «COVID+» relative ( %) spectral deltapower of EEG was significantly diffusely increased as well as absolute spectral delta-power in the left posterior-temporal area compared to NCG (p < 0.05). A significant diffuse increase in relative spectral theta-power with a bilateral excess in parietal areas (p < 0.05 – 0.01), as well as a significant increase in absolute spectral theta-power bilaterally in frontal areas (p < 0.05) was found in the group AFU «COVID+», compared to the group AFU «COVID-».
Conclusions. For the first time, a pronounced diffuse slowing of cerebral bioelectrical activity to delta-frequencies was detected in the Chornobyl clean-up workers being COVID-19 recuperates compared to the comparison group with chronic CVD. The AFU servicemen with previous COVID-19 have moderate persistent cerebral dysfunction. These changes require further observation and study.
Key words: Chornobyl disaster; Chornobyl clean-up workers; post-traumatic stress disorder; Armed Forces of Ukraine; quantitative electroencephalography (QEEG); COVID-19.