Prognostic Models for Mortality in Elderly Patients with Stenotrophomonas Maltophilia Bacteremia.

Background: This study was to determine risk factors and prognostic models for mortality in elderly patients with Stenotrophomonas maltophilia bacteremia.

Objective: The aim of this study was to address this gap, we conducted this study to investigate the predictors of mortality and develop prognostic models for clinical practice.

Methods: A retrospective study was conducted on 195 patients ≥ 60 years of age (median age 78 (68-85) years, 59.5 % male) at Thong Nhat National Teaching Hospital in Vietnam between January 1st, 2017 and December 31st, 2022. Patients who were treated in the hospital with the first positive blood culture for Stenotrophomonas maltophilia bacteremia were chosen for enrolment in this study. This investigation evaluated demographic and clinical characteristics and prognostic models for mortality.

Results: The mortality rate was 37.4 %. Multivariate analysis showed that the significant independent risk factors for mortality were age (aOR, 1.08; 95 % CI, 1.04-1.13; p < 0.001), SOFA score (aOR, 1.38; 95 % CI, 1.14-1.68; p < 0.001), and APACHE II score (aOR, 1.10, 95 % CI, 1.03-1.17; p = 0.005). Bayesian model averaging method identified four clinically applicable models: age combined with both SOFA score and APACHE II score (AUC 0.884, R2 0.564), age combined SOFA score (AUC 0.874, R2 0.516), age combined APACHE II score (AUC 0.800, R2 0.340), SOFA score combined APACHE II (AUC 0.846, R2 0.507).

Conclusion: Stenotrophomonas maltophilia bacteremia was severe in elderly patients with high mortality. Risk factors for mortality included age, SOFA, and APACHE II scores. The model comprising age, SOFA, and APACHE II scores has the best predictive ability. However, the model including age and SOFA score was also clinically valid and simple.