Impact of nosocomial infections in trauma: does age make a difference?

The effect of age and infection on outcome after trauma is unknown. We evaluated the incidence and impact that nosocomial infection (NI) and age have on morbidity and mortality. Several risk factors were identified and analyzed for correlation with infection.

Prospective data were collected on patients admitted for > or = 3 days over a 2-year period. Each patient was followed by an infectious disease specialist throughout their hospitalization. Centers for Disease Control and Prevention guidelines were used to diagnose infection.

Of the 3,254 patients admitted, 88% were < 65 and 12% were > or = 65 years of age. Injury Severity Score was not significantly different (older vs. younger). Five hundred one (17.4%) of the younger patients developed an NI with a significantly higher hospital length of stay (LOS), intensive care unit (ICU) LOS, and mortality compared with the noninfected group. One hundred forty-seven (39%) of the older group developed an NI and also had significant increases in hospital LOS, ICU LOS, and mortality. Older infected patients had the highest hospital LOS, ICU LOS, and mortality. The greatest relative risk of mortality was demonstrated with the combination of increased age and NI. Once infected, however, younger patients with penetrating trauma had a greater relative risk of mortality in the group-specific comparison. Many risk factors were associated with infection. Only chronic obstructive pulmonary disease in elderly trauma patients was a significant independent risk factor for infection.

NI significantly increases hospital LOS, ICU LOS, and mortality after injury. Age increases risk of infection matched for injury severity, with a significantly higher hospital LOS, ICU LOS, and mortality. Once infected, however, younger patients with penetrating trauma have the greatest risk of mortality. Chronic obstructive pulmonary disease in elderly trauma patients was found to be an independent predictor of infection.