Outcome in elderly patients with severe infection is influenced by sex hormones but not gender

Objective: The influence of gender as a prognostic variable in patients with severe infections is still controversial. Sex steroid hormones have an important impact on the immune system and vice versa, and prospective studies on the hormonal changes during severe infection are lacking. The objective was to compare the influences of gender and adrenal sex steroid hormone levels on hospital mortality rate in patients with infections. Design: Prospective observational study conducted between January 1995 and December 2000. Setting: University-based level I intensive care unit. Patients: Included were 208 males and 100 females with severe infection at admission to the ICU. Interventions: None. Measurements and Main Results: Mortality rate during hospitalization was analyzed for correlation to gender and the levels of testosterone, 17 beta-estradiol, and progesterone; source and clinical signs of infection; Acute Physiology and Chronic Health Evaluation II score; or age. There were no differences in demographic or infectious characteristics between males and females; the survival rate was similar. Males had significantly reduced testosterone levels. Elevation of the steroid hormones 17 beta-estradiol (1.5-fold), progesterone (5-fold), and cortisol (1.5-fold) occurred in both genders to the same extent. In addition, testosterone was elevated in septic females and correlated with 17 beta-estradiol. Nonsurvivors of both genders had significantly elevated 17p-estradiol levels. Progesterone was particularly high in nonsurviving males, whereas testosterone was elevated in nonsurviving females. Mortality rate was correlated with high 17p-estradiol and progesterone in males but with 17 beta-estradiol and testosterone in females. Cortisol or dehydroepiandrostenedione sulfate levels were not associated with mortality rates. Conclusions: In elderly patients with infections, mortality was not dependent on gender but was correlated with elevated 17 beta-pestradiol in both genders, with elevated progesterone in males and elevated testosterone in females. Although the latter sex hormones may derive from the adrenals, cortisol levels were only moderately increased and not associated with survival. The high 17 beta-estradiol concentrations implicate an increased aromatase activity. Therefore, other pathways of sex steroid production must be involved.