Prognostic Factors for Mortality in ICU Patients With Healthcare-Associated Infections: A Five-Year Institutional Analysis.

Background Healthcare-associated infections (HAIs) represent a major challenge in intensive care units (ICUs), leading to increased morbidity, prolonged hospitalization, and high mortality. Critically ill oncology patients are particularly vulnerable because of immunosuppression and frequent exposure to invasive devices. Objective This study aims to describe the epidemiology and microbiological profile of HAIs among oncology ICU patients over a five-year period and to identify independent risk factors for ICU mortality using multivariable analysis. Methods We conducted a single-center retrospective cohort study in the anesthesiology ICU of a tertiary oncology hospital between January 1, 2020, and December 31, 2024. Among 1,766 ICU admissions, 259 adult patients who developed at least one HAI (343 episodes in total) and met the inclusion criteria were analyzed. Data on demographics, comorbidities, infection characteristics, microbiology, and outcomes were retrieved from the hospital infection control surveillance system and medical records. Comparative analyses between survivors and non‑survivors were performed, and a parsimonious multivariable logistic regression model was constructed to identify independent predictors of ICU mortality. Model performance was assessed by the area under the receiver operating characteristic (ROC) curve (AUC) and the Hosmer-Lemeshow test. Results The median ICU length of stay (LOS) was 29 days (interquartile range (IQR): 17-49), and ICU mortality was 81.1% (n = 210). Pneumonia (including ventilator‑associated and hospital‑acquired pneumonia) was the most common HAI (45.1%, n = 117), followed by central line‑associated bloodstream infection (CLABSI) (35.1%, n = 91) and catheter‑associated urinary tract infection (CAUTI) (11.6%, n = 30).