More than one third of adults intubated for non-pulmonary conditions in intensive care units across Northern Italy developed ventilator-associated pneumonia within 15 days, according to research published on October 13, 2026, in Open Forum Infectious Diseases and covered by Medscape.
Researchers tracked 406 adults across eight Italian ICUs between 2021 and 2024 to measure how frequently secondary pneumonia struck patients who needed mechanical ventilation for reasons other than lung disease. Out of the total cohort, 148 patients developed ventilator-associated pneumonia during the 15-day window. The median time to onset was six days, and the overall incidence rate reached 43.2 per 1,000 ventilator-days at risk.
Patient Risk Factors and Clinical Variables
Adjusted analyses revealed distinct clinical variables associated with a lower risk of developing the infection. Female sex was linked to a lower risk compared with male sex, yielding an adjusted hazard ratio of 0.52. Patients admitted for a non-neurologic diagnosis faced roughly half the risk of those admitted for neurologic conditions, with an adjusted hazard ratio of 0.51.
Administering antibiotics during the first two days of ventilation also correlated with a reduced hazard ratio of 0.65. Antibiotic administration later in the hospital stay showed no statistically significant association with pneumonia risk. Among 107 endotracheal isolates gathered from 78 patients who contracted pneumonia, the predominant pathogens identified were Staphylococcus aureus, Klebsiella species, and Haemophilus influenzae. Multidrug-resistant organisms appeared in only four patients.
Study Design Limitations and Unresolved Questions
The prospective cohort study was originally designed to analyze lung microbiota rather than isolate specific risk factors. Consequently, the research was underpowered to detect certain subgroup differences, particularly regarding individual antibiotic classes. Investigators diagnosed ventilator-associated pneumonia clinically, and roughly half of those episodes lacked microbiological confirmation.
Furthermore, researchers did not document the specific clinical indication for each individual antibiotic prescription, meaning confounding by indication cannot be ruled out. Laura Alagna of the Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico in Milan led the investigation.
Although our study did not investigate mechanistic pathways, [the] findings support consideration of sex in VAP risk stratification,
the study authors wrote.
Frequently Asked Questions
Which patients faced the highest vulnerability in the Italian cohort?
Patients admitted with neurologic diagnoses and male patients experienced higher rates of ventilator-associated pneumonia compared to female patients and those admitted for non-neurologic reasons.
What bacteria caused the most infections?
Staphylococcus aureus, Klebsiella species, and Haemophilus influenzae were the most common pathogens found in endotracheal isolates from patients who developed pneumonia.
How quickly did infections typically appear after intubation?
The median time to the onset of ventilator-associated pneumonia was six days, with the vast majority of tracked cases developing within the initial 15-day observation window.
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