The severity and risk factors for mortality in immunocompromised adult patients hospitalized with influenza-related pneumonia

Objective To explore disease severity and risk factors for 30-day mortality of adult immunocompromised (IC) patients hospitalized with influenza-related pneumonia (Flu-p). Method A total of 122 IC and 1191 immunocompetent patients hospitalized with Flu-p from January 2012 to December 2018 were recruited retrospectively from five teaching hospitals in China. Results After controlling for confounders, multivariate logistic regression analysis showed that immunosuppression was associated with increased risks for invasive ventilation [odds ratio: (OR) 2.475, 95% confidence interval (CI): 1.511-4.053, p < 0.001], admittance to the intensive care unit (OR: 3.247, 95% CI 2.064-5.106, p < 0.001), and 30-day mortality (OR: 3.206, 95% CI 1.926-5.335, p < 0.001) in patients with Flu-p. Another multivariate logistic regression model revealed that baseline lymphocyte counts (OR: 0.993, 95% CI 0.990-0.996, p < 0.001), coinfection (OR: 5.450, 95% CI 1.638-18.167, p = 0.006), early neuraminidase inhibitor therapy (OR 0.401, 95% CI 0.127-0.878, p = 0.001), and systemic corticosteroid use at admission (OR: 6.414, 95% CI 1.348-30.512, p = 0.020) were independently related to 30-day mortality in IC patients with Flu-p. Based on analysis of the receiver operating characteristic curve (ROC), the optimal cutoff for lymphocyte counts was 0.6 x 10(9)/L [area under the ROC (AUROC) = 0.824, 95% CI 0.744-0.887], sensitivity: 97.8%, specificity: 73.7%]. Conclusions IC conditions are associated with more severe outcomes in patients with Flu-p. The predictors for mortality that we identified may be valuable for the management of Flu-p among IC patients.