Gender differences in ECG markers of increased risk for malignant arrhythmias, peripheral blood parameters, and adverse outcomes in patients with COVID-19 pneumonia

Background: The available data on gender differences in a) markers of cardiac involvement, b) peripheral blood parameters, and c) clinical adverse outcomes related to COVID-19 pneumonia severity are limited in the literature.: Objectives: To investigate gender differences in ECG markers of increased risk for malignant arrhythmias. This includes T from peak to end (Tp-e) interval, corrected QT (QTc), transmural dispersion of repolarization (TDR)(Tp-e/QTc), and index of cardiac electrophysiological balance (iCEB)(QTc/QRS), peripheral blood parameters, and in-hospital adverse outcomes in patients with COVID-19 pneumonia. Methods: A cross sectional study enrolled patients with COVID-19 pneumonia admitted to hospital from August 20th, to September 30th, 2020. Results: A total of 197 patients were included. Ninety-six (47%) were men and 101 women. There were no significant gender related differences concerning comorbidities. Men had higher QRS values, Tp-e interval and TDR, and lower values of iCEB. No significant gender differences were observed in the distribution of QTc interval. Men stayed longer in the hospital and had more extensive lung injury than women. In men, prolonged QTc interval, low lymphocytes %, high platelet distribution width (PDW), and low hemoglobin (Hb) were the main predictors of adverse in-hospital outcome, while prolonged QTc interval, high PDW, and low platelet count were the main predictors of adverse in-hospital outcome for women. Conclusions: Men had higher TDR values, lower iCEB, stayed longer in the hospital, and had more extensive lung injury than women, suggesting that, despite that there was no significant difference in mortality incidents between the two genders, the difference in surrogate markers may indicate that men are at a higher risk for adverse outcomes.