title: Does gender difference influence outcome?
abstract: BACKGROUND
  Recent laboratory studies have demonstrated that immune responses differ between male and female rodents, and some clinical studies have suggested gender differences regarding incidence and mortality from sepsis. The differences appear because of both deleterious testosterone and beneficial estrogen effects; clinical trials of testosterone blockage and/or estrogen administration for male subjects have been suggested. We evaluated the effect of gender on various outcomes in trauma patients.
  
  
  METHODS
  Trauma patients over a 52-month period were identified from the trauma registry. Early deaths were excluded. Outcomes included mortality, pneumonia (> or = 10 colony-forming units/mL in bronchoalveolar lavage effluent), acute respiratory distress syndrome, bacteremia, ventilator days, and intensive care unit and hospital length of stay. Patients were stratified by injury mechanism, gender, age (assuming women < or = 40 were premenopausal and those > 50 were postmenopausal), and injury severity.
  
  
  RESULTS
  There were 18,133 patients identified, and 544 were excluded because of early death. There were 12,756 (73%) men and 4,833 (27%) women. There were no outcome differences after penetrating injury with respect to gender and age group. There was a survival advantage for women < or = 40 in the Injury Severity Score 16 to 24 group, but these patients had statistically less severe injury. Overall, men tended to have more infectious complications, but women had lower survival in the face of infection. Logistic regression did not identify gender as an independent predictor of mortality.
  
  
  CONCLUSIONS
  Although there was a survival advantage for women in subgroup analysis, there was no overall difference in mortality. Women with pneumonia, however, had a higher mortality than men. Further understanding of potential mechanisms is necessary before hormonal manipulation studies.
authors.affiliation: Department of Surgery, University of Tennessee Health Science Center, Memphis 38163, USA. mcroce@utmem.edu
authors.forename: Martin A
authors.initials: MA
authors.lastname: Croce
authors.forename: Timothy C
authors.initials: TC
authors.lastname: Fabian
authors.forename: Ajai K
authors.initials: AK
authors.lastname: Malhotra
authors.forename: Tiffany K
authors.initials: TK
authors.lastname: Bee
authors.forename: Preston R
authors.initials: PR
authors.lastname: Miller
mesh_terms: D000328:Adult; D016009:Chi-Square Distribution; D004967:Estrogens / Q000494:pharmacology*; D005260:Female; D006801:Humans; D015601:Injury Severity Score; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D017063:Outcome Assessment, Health Care; D012727:Sex Characteristics; D016019:Survival Analysis; D014947:Wounds and Injuries / Q000401:mortality*
chemical_list: D004967:Estrogens