Risk Factors of 90-Day Mortality in Patients with Critical Covid-19 Infection

Aim: Mortality risk factors and effective treatment approaches are still uncertain for the SARS-CoV-2. In this study, we aimed to determine risk factors of 90-day mortality critically ill patients with COVID-19 infection. Materials and Methods: All patients hospitalized in the intensive care unit of the university hospital with the diagnosis of COVID-19 pneumonia between 15 March and 30 November 2020 were reviewed in this retrospective study. The primary endpoint was 90-day mortality, while the secondary endpoints were in-hospital mortality, therapy responses for tocilizumab and corticosteroid treatments, duration of mechanical ventilation (MV), and length of hospital stay. Results: A total of 145 patients, 105 (73%) men and 40 (27%) women were included in the study. Median age was 71.0 (58-79.50) years. In-hospital mortality was 62.8%, 28-day mortality was 60%, and 90-day mortality was 66.9% for the whole study population. In-hospital mortality was 58.4% (n=52) and 90-day mortality was 64.0% (n=57) in patients receiving corticosteroid treatment. Both in-hospital and 90-day mortality was found as 60% (n=12) in patients receiving tocilizumab. Age and duration of invasive mechanical ventilation were determined as independent risk factors on logistic regression analysis performed for 90-day mortality (OR 1.060 (1.018-1.103), p=0.005 and OR 1.057 (1.004-1.113, p=0.035), respectively). Conclusions: Early and late mortality is high in patients with severe COVID 19 infection. Our results showed advanced age and duration of mechanical ventilation are independent risk factors for 90-day mortality. However long-term effect of corticosteroid and tocilizumab treatments on survival could not be demonstrated in this study.