“…Recent reports showed an important variability in COVID-19 mortality rate in Italy for hospitalized patients depending on individual prognostic factors and also depending on the pandemic wave, being at a lower risk of death patients hospitalized after the first wave [ 30 ]. Older age seems to have, in general, an important impact on mortality in COVID-19 patients as reported in previous studies and meta-analyses [ 9 , 31 , 32 ] and, more specifically, some studies reported a correlation with older age and a negative prognosis in COVID-19 patients with PNX [ 15 , 33 ]. In our cohort the elevated rate of mortality may partly be explained by the older age of the patients (median age in PNX group 81 years) and partly by the severity of illness at admission.…”