Background Patients with COVID-19 present with a variety of clinical manifestations, ranging from mild or asymptomatic disease to severe illness and death. Whilst previous studies have clarified these and several other aspects of COVID-19, one of the ongoing challenges regarding COVID-19 is to determine which patients are at risk of adverse outcomes of COVID-19 infection. It is hypothesized that this is the result of insufficient inhibition of the immune response, with the vagus nerve being an important neuro-immuno-modulator of inflammation. Vagus nerve activity can be non-invasively indexed by heart-rate-variability (HRV). Therefore, we aimed to assess the prognostic value of HRV, as a surrogate marker for vagus nerve activity, in predicting mortality and intensive care unit (ICU) referral, in patients hospitalized with COVID-19. Methods A retrospective cohort study including all consecutive patients (n = 271) diagnosed and hospitalized with COVID-19 between March 2020 and May 2020, without a history of cardiac arrhythmias (including atrial and ventricular premature contractions), pacemaker, or current bradycardia (heart rate <50 bpm) or tachycardia (heart rate >110 bpm). HRV was based on one 10s ECG recorded at admission. 3-week survival and ICU referral were examined. Results HRV indexed as standard deviation of normal to normal heartbeat intervals (SDNN) predicted survival (H.R. = 0.53 95%CI: 0.31–0.92). This protective role was observed only in patients aged 70 years and older, not in younger patients. HRV below median value also predicted ICU referral within the first week of hospitalization (H.R = 0.51, 95%CI: 0.29–0.90, P = 0.021). Conclusion Higher HRV predicts greater chances of survival, especially in patients aged 70 years and older with COVID-19, independent of major prognostic factors. Low HRV predicts ICU indication and admission in the first week after hospitalization.
【초록키워드】 COVID-19, Inflammation, immune response, Hospitalized, Mortality, intensive care, Hospitalization, intensive care unit, risk, adverse outcomes, ICU, ECG, Cardiac arrhythmia, adverse outcome, clinical manifestations, survival, COVID-19 infection, pacemaker, Patient, death, Prognostic factors, Mild, Premature, heart rate, Asymptomatic disease, Admission, predict, marker, bradycardia, independent of, vagus nerve, retrospective cohort study, cardiac arrhythmias, Standard deviation, Tachycardia, Prognostic value, Older, Previous studies, younger patients, protective role, previous study, median value, HRV, independent, Premature contractions, Result, greater, predicted, examined, diagnosed, determine, variety, interval, recorded, bpm, consecutive patient, patients hospitalized, ventricular, with COVID-19, 【제목키워드】 COVID-19, outcome, predict, HRV,