Effect of Sepsis-3 Definition on the Classification of Patients with Sepsis or Septic Shock in South Korea.

Background: Little is known about differences in patient characteristics before and after implementation of the new definition of sepsis (Sepsis-3) and whether the new definition is affecting clinical practice in intensive care units.

Objective: To examine and compare the clinicoepidemiologic characteristics of patients with sepsis or septic shock before and after implementation of Sepsis-3.

Methods: In this population-based cohort study, a nationwide registration database in South Korea was used to identify patients with sepsis or septic shock. Patients admitted to hospitals from 2012 to 2015 constituted the Sepsis-2 group, and patients admitted from 2017 to 2020 constituted the Sepsis-3 group.

Results: The study involved 443 217 patients, of whom 170 660 (38.5%) were in the Sepsis-2 group and 272 557 (61.5%) were in the Sepsis-3 group. The mean (SD) age was 73.3 (14.5) years in the Sepsis-2 group and 75.5 (14.5) years in the Sepsis-3 group. The intensive care unit admission rate was higher in the Sepsis-2 group (34.6%, 59 081 of 170 660) than in the Sepsis-3 group (21.3%, 57 997 of 272 557). Multivariable Cox regression analysis showed that 1-year all-cause mortality was 21% lower in the Sepsis-3 group than in the Sepsis-2 group (hazard ratio, 0.79; 95% CI, 0.78-0.79; P < .001).

Conclusions: Implementation of the Sepsis-3 definition was associated with an increased number of patients with sepsis. Other findings suggested that patients in the Sepsis-2 group had more severe illness, with increased 1-year all-cause mortality, compared with those in the Sepsis-3 group.