Risk factors for in-hospital mortality in older patients with acute respiratory distress syndrome due to COVID-19: a retrospective cohort study

BACKGROUND: Advancing age is associated with an increase in mortality among patients with acute respiratory distress syndrome (ARDS) due to coronavirus disease 2019 (COVID-19). This study aimed to determine risk factors for in-hospital mortality in patients over 60 years old with COVID-19-related ARDS (C-ARDS).

METHODS: This was an observational, analytical, retrospective study conducted on a cohort that included all patients aged 60 years or older diagnosed with COVID-ARDSwho were admitted to a high-complexity hospital in Bogotá, Colombia, between March 2020 and July 2021.

RESULTS: A total of 1563 patients were included in the analysis, with a median age of 73 years (interquartile range [IQR]: 67-80) and 811 deaths (51.8%). Independent risk factors for in-hospital mortality were identified as follows: patients aged 71-80 [OR 1.87 (95% CI 1.33-2.64)], age > 80 [OR 8.74 (95% CI 5.34-14.31)], lactate dehydrogenase (LDH) [OR 1.009 (95% CI 1.003-1.0015)], severe C-ARDS [OR 2.16 (95% CI 1.50-3.11)], use of invasive mechanical ventilation (IMV) [OR 12.94 (95% CI 9.52-17.60)], and use of steroids [OR 1.49 (95% CI 1.09-2.03)]. In patients over 80 years of age (n = 388), the primary risk factor associated with in-hospital mortality was the use of IMV (n = 76) [OR 6.26 (95% CI 2.67-14.69)], resulting in an in-hospital mortality rate of 89.4% (n = 68) when this therapy was implemented.

CONCLUSIONS: The primary risk factors for in-hospital mortality in patients older than 60 years were age, the use of IMV, the severity of C-ARDS, use of steroids and elevated LDH values. Among patients older than 80 years, the main risk factor for in-hospital mortality was the use of IMV. In cases of C-ARDS in older patients, the decision to initiate IMV should always be individualized; therefore, the use of alternative oxygen delivery systems as the first-line approach can be considered.