Hospital-Acquired Infections in Elderly Versus Younger Patients in an Acute Care Hospital

Abstract

Background: A growing number of elderly patients are hospitalized for various causes and age has been described inconsistently as a risk factor for acquiring nosocomial infections with a subsequent higher mortality rate compared to younger patients. Objectives: To describe the incidence, type, and microbiological characteristics of nosocomial infections in elderly and non-elderly patients. Patients and Methods: Retrospective analysis of all hospital-acquired infections (HAIs) in an academic community hospital. Patients were stratified into two groups: non-elderly (18 - 64 years) and elderly (> 65 years). Results: A total of 18469 patients were included (108555 hospital days) in this study. About 79.6% of HAI were infected non-elderly and 20.3% elderly (P < 0.0001) patients. Higher infection rates for ventilator-associated pneumonia (VAP), secondary bacteremia, and catheter-associated urinary tract infections were noted for elderly as well as a higher frequency of positive cultures for Gram-negative bacteria, particularly Klebsiella spp. and fungal infections (P > 0.05). Hospital mortality increased with every HAI diagnosed per patient. Conclusions: The study showed that HAIs were more frequent in elderly population predominately with respect to VAP and infections by Gram-negative pathogens. Overall mortally was greater in the elderly group although the odds ratio for death was higher in younger patients and increased with every HAI diagnosed.