Evaluation of qSOFA as a Predictor of Mortality Among ICU Patients With Positive Clinical Cultures-A Retrospective Cohort Study

Objective: To compare the discriminative value of the quick-sequential organ failure assessment score (qSOFA) to SOFA in a critically ill population, in which a microbial pathogen was isolated within 48 hours of admission to intensive care.

Design: Retrospective cohort study.

Setting: Academic tertiary referral center from July 2008 to June 2017.

Patients: Hospitalized patients admitted to intensive care unit.

Interventions: None.

Measurements and main results: The primary outcome was in-hospital mortality for all patients with confirmed positive microbiological cultures within 48 hours of admission to intensive care unit (ICU). Subgroup analysis was performed on patients with pathogenic bacteremia or positive cultures in cerebrospinal fluid. Of the 11 415 patients analyzed with positive microbiology specimens within 48 hours of admission, 2933 (25.7%) had a qSOFA ≥2. Of these, 16.6% reached the primary outcome of in-hospital mortality. Unsurprisingly, the discriminative value of qSOFA on admission was significantly worse than that of SOFA (0.73 vs 0.76; P = .0004), despite observing a significant association between qSOFA category and in-hospital mortality (P < .0001). In secondary analyses, similar observations were found using qSOFA within 6 and 24 hours of ICU admission. When analysis was focused on patients with pathogenic bacteremia or positive cerebrospinal fluid (CSF) cultures (n = 1646), there was no significant difference between the discriminative value of qSOFA and SOFA (0.75 vs 0.78; P = .17).

Conclusions: Quick-sequential organ failure assessment score at admission was not superior to SOFA in predicting in-hospital mortality in patients with positive clinical cultures within 48 hours of admission to ICU. Quick-sequential organ failure assessment score at admission to the ICU was associated with mortality and showed reasonable calibration and discrimination. When the analysis was focused on patients with pathogenic bacteremia or positive CSF cultures, qSOFA performed similarly to SOFA in discriminatory those who will die from sepsis.