Abstract

Background: Klebsiella pneumoniae pneumonia is a significant threat to elderly populations, but prospective data from high-prevalence regions like Vietnam are scarce. Objective: To identify risk factors for multidrug-resistant (MDR) infection and independent predictors of in-hospital mortality in elderly Vietnamese patients. Methods: A prospective cohort study was conducted at a tertiary geriatric center in Vietnam, enrolling 293 consecutive patients aged ≥60 years with culture-confirmed K. pneumoniae pneumonia. Multivariable logistic regression models were used to identify risk factors for MDR and independent mortality predictors. Results: The median age was 81 years (IQR 72-87), with in-hospital mortality of 25.3% and MDR prevalence of 38.6%. Multivariable analysis identified ICU admission (AOR 4.29), proton pump inhibitor (PPI) use (AOR 2.15), and COPD (AOR 2.03) as independent MDR risk factors, while appropriate initial antibiotic therapy was strongly protective (AOR 0.15). The strongest independent mortality predictors were invasive mechanical ventilation (AOR 11.07), severe pneumonia (AOR 3.73), and APACHE II score (AOR 1.08). The mortality model demonstrated excellent discrimination (AUC = 0.904, pHosmer-Lemeshow = 0.462). Conclusion: In-hospital mortality for K. pneumoniae pneumonia in elderly Vietnamese patients is high. ICU admission, PPI use, and COPD are key independent risk factors for MDR infection. Invasive mechanical ventilation, severe pneumonia, and a high APACHE II score are the most critical independent determinants of death. The high-performance mortality prediction model developed here may serve as a practical tool for risk stratification.

Key words: lebsiella pneumoniae, pneumonia, aged, risk factors, mortality.