Abstract
Septic shock survival rate and host immune response are intimately interlaced. In the last years, biological and pre-clinical studies demonstrated sex-specific differences in the immune response to infection. In the hypothesis that survival rate is related to the hormonal framework, the aim of the present study was to observe sex-specific differences in 28-day mortality rate between women of childbearing potential and same-age men. This multicenter study was conducted in six Italian intensive care units (ICUs). We enrolled consecutive patients ≤ 55 years old admitted to the Intensive Care Unit from January 2011 to January 2020, who were diagnosed with septic shock at the time of ICU admission or during the ICU stay. We gathered baseline characteristics and outcomes. The primary outcome was 28-day mortality; secondary outcomes included ICU mortality, in-hospital mortality and length of stay in the ICU and in the hospital. Moreover, data from >55 years old patients were collected and analyzed. We enrolled 361 young patients with septic shock: 215 were males (60%) and 146 females (40%). While baseline and ICU characteristics were similar between the two groups, males had a higher 28-day mortality rate (39.5% vs. 29%, p = 0.035), ICU mortality rate (49%vs. 38%, p = 0.040) and hospital mortality rate (61% vs. 50%, p = 0.040) as compared to females. Findings were confirmed in patients with septic shock at ICU admission. Young adult females developed septic shock less frequently than young males, displaying a reduced mortality rate as compared to that of their same-age male counterpart. These findings may stimulate future research and therapies.