COVID-19 associated pneumonia versus non-COVID-19 viral pneumonia: a comparison of hospitalization outcomes (retrospective cohort study with pseudo-randomization)

Introduction. The COVID-19 pandemic has exposed the inadequacy of treatment strategies for viral pneumonia, highlighting the need for new treatment approaches.

Objective. To compare hospitalization outcomes between patients with COVID-19 pneumonia and those with non-COVID viral pneumonia.

Materials and methods. This retrospective cohort study compared hospitalization outcomes of patients with COVID-19 pneumonia treated in Intensive Care Unit of Demikhov Hospital, 2019–2020, with those of patients with non-COVID viral pneumonia (data from the eICU-CRD database). Propensity score matching (PSM) was used to adjust for confounding factors, including age, sex, and comorbidities. Assessed outcomes included hospital length of stay, duration of MV, ventilator-free days, and incidence of complications.

Results. A total of 511 patients were included, with 104 patients matched in each group after PSM. Hospital mortality was higher among patients with COVID-19 pneumonia (41.3 vs. 6.7 %, p<0.001), especially in those requiring MV (87.8 vs. 8.8 %, p<0.001). The median hospital and ICU lengths of stay were longer in the COVID-19 group (15.5 and 7.1 days vs. 5.0 and 3.8 days, p<0.001 and p=0.002, respectively). Among survivors, the duration of MV was longer in the COVID-19 group (10.0 vs. 4.0 days; p=0.039).

Conclusions. COVID-19 pneumonia is associated with greater severity, higher mortality and prolonged hospitalization. Mortality among MV was ten times higher and complications occurred more frequently.

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