At multivariable analysis, having haematological malignancy [OR4.76, p < 0.001], chronic corticosteroid therapy [OR3.65, p = 0.004], prior infections [OR57.7, p = 0.006], thrombocytopenia [OR3.03, p < 0.001] and neutropenia [OR31.1, p = 0.001], low albumin levels [OR3.1, p = 0.001] and ≥ 10 days from hospital admission to respiratory worsening [OR3.3, p = 0.002] were independently associated with mortality. This evidence concerns the gene ALB and neutropenia.