Gender impact on the outcomes of critically ill patients with nosocomial infections

Objectives. To investigate gender impact on the outcomes of severe nosocomial infections (pneumonia, bacteremia, catheter-related bloodstream infections, poststernotomy mediastinitis, urinary infections) occurring in a large cohort of patients hospitalized in a medical-surgical intensive care unit. Highly controversial data exist regarding gender-related differences in outcomes of severe nosocomial infections, reflecting potential confounders related to case-mixes or heterogeneity of populations evaluated. Design: Retrospective study of patients admitted to our intensive care unit. Multivariable logistic regression-analysis was used to control for confounders in the evaluation of gender impact on intensive care unit death post nosocomial infections. Setting. An 18-bed tertiary referral medical-surgical intensive care unit in a teaching hospital. Patients. Mixed population of patients who developed nosocomial infections in the intensive care unit. Measurements and Main Results. Among the 5081 patients admitted to our intensive care unit from 1995 to 2004, 1341 (34% women) developed nosocomial infections. Pneumonia and mediastinitis were more frequent in men (51% vs. 44%, p = .01 and 29% vs. 22%, p = .01, respectively) whereas urinary infections predominated for women (46% vs. 24%, p < .001). Durations of mechanical ventilation and intensive care unit stays and treatment intensity did not differ between genders. However, intensive care unit mortality was higher for women (37% vs. 32%, p = .06) and this excess mortality was statistically significant (odds ratio = 1.50, 95% Confidence Interval = 1.11-2.03), after controlling for other independent risk factors of intensive care unit death. Compared with those observed for men of the same subgroup, crude ICU death rates were significantly higher for women who developed pneumonia, who were <50 yrs old or had undergone heart surgery before intensive care unit admission. However, multivariable analyses retained feminine gender as significantly associated with mortality only for the last subgroup. Conclusions. Female intensive care unit patients developing nosocomial infections seem to be at increased risk of intensive care unit mortality, after carefully controlling for other prognostic factors. Further studies are needed to elucidate the pathophysiology underlying this gender-related difference, to devise tailored gender-specific therapies that might improve Outcomes. (Crit Care Med 2009; 37:2506-2511)