(1448) SOFA Scores and 30-Day Mortality in Critically Ill Patients With Sepsis

Introduction: The current Sepsis-3 criteria utilize the Sequential Organ Failure Assessment (SOFA) score to identify infection-induced organ dysfunction. SOFA score sepsis onset shows promise in predicting 30-day mortality. We hypothesized that measuring the SOFA score several days after the onset of sepsis would provide a more accurate prediction of mortality, considering the common delay between the onset of organ dysfunction and the laboratory results used to define it.

Methods: We conducted a prospective, observational clinical study at a quaternary care academic medical center. The study included 147 adults with sepsis who presented with acute respiratory failure and required critical care therapy in a medical intensive care unit (MICU). Sequential SOFA scores were measured every 48 hours, totaling 14 days from admission to either death (n=?) or hospital discharge (n=?). Our main independent variables were SOFA, delta SOFA (changes between two consecutive 48-hour periods), and the area under the curve (AUC) for SOFA score over time. The primary outcome was 30-day mortality. We externally validated our results using the MIMIC-IV data from 73,163 patients.

Results: The highest Pearson correlations were observed between the day 3 SOFA score (r=0.34) and SOFA AUC between days 1-3 (r=0.34), and 30-day mortality using the MICU dataset. Logistic regression analysis based on SOFA days 1 and 3 revealed that, for each unit increase in SOFA (on day 3), log-odds likelihood of mortality increased by 0.09 (p=0.024). MIMIC-IV data confirmed a Pearson correlation of r=0.34 between SOFA day 3 and mortality. SOFA day 3 was associated with a mortality odds ratio of 1.28 (95% CI 1.27-1.29). While logistic regression models based on SOFA days 1 and 3 were significantly associated with mortality, MIMIC-IV data also supported the use of logistic regression models for predicting survival that were based both on SOFA AUC and delta SOFA between days 1 and 3.

Conclusions: While the SOFA on day 1 is required to diagnose sepsis according to Sepsis-3 criteria, SOFA values measured on subsequent days of septic illness may be more closely associated with sepsis-related 30-day mortality. Among the SOFA scores measured during the first 14 days of sepsis, the SOFA score on day 3 appears best suited for predicting 30-day mortality rates.