Sex differences in children with severe health conditions: Causes of admission and mortality in a Pediatric Intensive Care Unit

Based on the existing sex differences in mortality rates in children, we would like to explore whether girls and boys respond differently under severe health conditions, in terms of mortality and cause of admission.We analyzed demographic characteristics (age and sex), causes of admission, clinical parameters, and mortality in a sample of 2,609 patients from a Pediatric Intensive Care Unit (PICU) in a children's hospital in Barcelona, Spain.PICU admittance was significantly higher in boys (57.5% vs. 42.5%) whereas PICU mortality was significantly higher in girls (4.9% vs. 3.3%). Female sex was a risk factor for PICU in-hospital mortality (OR = 1.55, P = 0.033), while increasing age had a protective effect (OR = 0.808, P = 0.021). In cases of PICU mortality, girls died from a broader range of causes and boys were more affected by respiratory and polytraumatic injuries. Boys were affected by polytraumatic injuries throughout the year, less frequently in winter, while girls showed a higher occurrence in holiday months.Although more boys were admitted to the PICU, a significantly higher number of girls died. Younger age and higher occurrence of nosocomial infection among girls could explain this finding. More frequent polytraumatic injuries in boys could reflect an increased exposure to risky activities and/or more careless behavior.