An older age is associated with severe progression and poor prognosis in coronavirus disease 2019 (COVID-19), and mechanical ventilation is often required. The specific characteristics of older patients undergoing mechanical ventilation and their prognostic factors are largely unknown. We aimed to identify potential prognostic factors in this group to inform treatment decisions. This retrospective cohort study collected data from patients with COVID-19 at 22 medical centers. Univariate and multivariate Cox regression analyses were performed to assess factors that influence mortality. We allocated 434 patients in geriatric (≥80 years) and elderly (65–79 years) groups. The former group scored significantly higher than the elderly group in the clinical frailty scale and sequential organ failure assessment, indicating more severe organ dysfunction. Significantly lower administration rates of tocilizumab and extracorporeal membrane oxygenation and higher intensive care unit (ICU) and in-hospital mortality were noted in the geriatric group. The factors associated with ICU and in-hospital mortality included high creatinine levels, the use of continuous renal replacement therapy, prone positioning, and the administration of life-sustaining treatments. These results highlight significant age-related differences in the management and prognosis of critically ill older patients with COVID-19. Increased mortality rates and organ dysfunction in geriatric patients undergoing mechanical ventilation necessitate age-appropriate treatment strategies to improve their prognoses.

COVID-19 pandemic was accompanied by many healthcare-related issues. Concrete national data regarding the care performance of critical ill cases of COVID-19 does not exist in Korea. The current study aimed to describe the treatment outcome and healthcare resource utilization of critically ill COVID-19 patients. Our multicenter retrospective cohort study enrolled critically ill COVID-19 patients from 22 tertiary care hospitals in Korea. Inclusion criteria: (1) patients aged 19 years or older, (2) patients with laboratory-confirmed SARS-CoV-2 infection who received at least one of following initial treatments such as high-flow oxygen therapy (HFOT) or noninvasive ventilation (NIV) or invasive mechanical ventilation (IMV) or extracorporeal membrane oxygenation. During the study wave, a total of 1358 eligible participants were enrolled, with 21 institutions participating in the study. Among them, data from 1113 patients were available and analyzed. Of 921 (82.7%), 621 (55.8%) were supported by IMV. Of the 921 patients supported by HFOT or NIV, 438 (47.6%) recovered without IMV, 429 (46.6%) required IMV, and 54 died who DNR after NIV was applied. Prone position ventilation was administered to 163 (33.1%) patients with IMV and 25 (6.2%) patients with HFOT. Extracorporeal membrane oxygenation was administered to 128 (20.6%) patients treated with IMV. The overall mortality rate was 26.4%. In South Korea, mortality rates for patients with severe COVID-19 pneumonia have been shown substantial fatality, with the highest mortality rates observed in wave 3. The increased mortality rate in wave 3 could be associated with the rapid escalation of critically ill COVID-19 patients and the consequent saturation of intensive care unit capacities. Patients received NIV therapy and prone position ventilation more frequently in wave 3 as the number of cases increased.