European Journal of Cardiovascular Medicine

Sepsis is a complex, life-threatening condition characterized by acute organ dysfunction resulting from a dysregulated host response to infection. Despite advances in medical care, sepsis remains a major cause of morbidity and mortality worldwide, largely due to delayed recognition and inadequate early intervention. Over time, the clinical definitions and diagnostic criteria for sepsis have evolved in response to a deeper understanding of its underlying pathophysiology. Initially defined by the presence of suspected or confirmed infection alongside systemic inflammatory response syndrome (SIRS) criteria, the approach to diagnosing sepsis has shifted significantly. In 2016, the Third International Consensus Definitions for Sepsis and Septic Shock (Sepsis-3) redefined sepsis as life-threatening organ dysfunction caused by a dysregulated host response to infection, replacing SIRS with more accurate tools for early detection and prognosis [1]. The Sequential Organ Failure Assessment (SOFA) score, introduced by Sepsis-3, quantifies the extent of organ dysfunction across six physiological systems, making it a reliable tool for risk stratification and predicting mortality in ICU patients [2]. For patients outside the ICU, the quick SOFA (qSOFA) score was developed as a simplified bedside assessment tool, incorporating three clinical parameters: respiratory rate ≥ 22/min, altered mental status, and systolic blood pressure < 100 mmHg. A qSOFA score of ≥2 is associated with increased mortality and prompts further evaluation using the full SOFA score [3]. Given the practicality of qSOFA in resource-limited or emergency settings and the comprehensive accuracy of SOFA in ICU, this study aims to compare their predictive power for mortality in critically ill patients with sepsis admitted to a tertiary care ICU.

AIMS & OBJECTIVES:  The aim of this study is to compare the performance of the SOFA and qSOFA scores in predicting in-hospital mortality among critically ill patients with sepsis in an ICU setting at a tertiary care center. The primary objective is to validate the effectiveness of the qSOFA score for predicting in-hospital mortality in comparison to the more comprehensive SOFA score. The secondary objective is to assess the utility of qSOFA in predicting 28-day mortality outcomes in sepsis patients and compare its predictive accuracy with that of the SOFA score.

This study was conducted in the Department of Medicine at Kurnool Medical College, Kurnool, involving patients admitted to the ICU of Government General Hospital. The study period was 14 months, from November 2019 to January 2021. Ethical clearance was obtained from the institutional review board prior to starting the research. Adults aged over 18 years with suspected or confirmed infection admitted within 24 hours were included after providing written informed consent. Patients below 18 years, those who refused consent, had terminal malignancy (ECOG >3), or had cardiogenic shock due to heart failure were excluded. Sepsis was defined as life-threatening organ dysfunction caused by an abnormal immune response to infection. Two scoring systems were used: SOFA (Sequential Organ Failure Assessment), which evaluates dysfunction in six organ systems, and qSOFA (quick SOFA), which uses three simple criteria—systolic blood pressure <100 mmHg, respiratory rate >22/min, and altered mental status. A qSOFA score of 2 or more indicated a higher risk of poor outcome. Upon admission, patients were evaluated using a questionnaire to collect clinical data, and both qSOFA and SOFA scores were recorded. Patients were followed during hospitalization and up to 28 days post-admission to monitor outcomes, particularly mortality. Data were analyzed using statistical tools. Categorical data were expressed in percentages, and continuous variables were shown as mean or median. Tests like the Chi-square test, t-test, or Wilcoxon rank-sum test were applied based on the type of data. Predictive accuracy was assessed using AUROC values for both scoring systems. Baseline models included demographic and clinical factors available at admission to adjust and compare the scores' performance.

Fifty patients with a clinical diagnosis of confirmed or suspected sepsis who met the inclusion criteria and provided informed consent were enrolled in the study. They were followed from admission through discharge and up to 28 days post-discharge. The average age of the participants was 54 years, with 56% males and 44% females. The mean duration of symptoms before seeking medical care was 8.14 days. A high prevalence of comorbidities, especially diabetes mellitus (78%), was noted among the study population. Gender distribution was generally balanced, although males were predominant in the 57–70 age group. At the time of discharge, mortality was observed to be 22%, with 11 out of 50 patients succumbing to the illness. Of the remaining 39 patients, a 28-day post-discharge follow-up revealed an additional 9 deaths, raising the cumulative post-discharge mortality rate to 23.07%. This brought the total number of survivors at 28 days to 30.

Patients presented with a variety of clinical symptoms. Fever was the most common symptom (96%), followed by respiratory distress (64%). Altered sensorium was also noted in a significant subset of patients. Laboratory evaluations revealed a mean total WBC count of 18,104/mm³, with 85.71% neutrophil predominance. The average Procalcitonin level was 22.5 ng/mL, and the mean C-reactive protein (CRP) level was 66.39 mg/L, indicating systemic inflammation.

Figure 1: ROC curve of SOFA (vs) q-SOFA mortality using sensitivity and specificity at discharge

To assess the predictive value of clinical scoring systems, both the SOFA and qSOFA scores were analyzed in relation to patient outcomes. The SOFA scores ranged from 0 to 24, with a median value of 11. Patients were categorized based on this median, and mortality was found to be significantly higher in those with scores above 11. Among the 16 patients (Fig 1) with SOFA scores above 11, 8 died within 28 days of discharge.

Similarly, higher qSOFA scores (≥2) were associated with increased mortality. These findings highlight the value of SOFA and qSOFA scores in predicting adverse outcomes in sepsis and support their use in early risk stratification and clinical decision-making.

This prospective cohort study aimed to assess the predictive accuracy of mortality in sepsis using SOFA and qSOFA scoring systems and to determine their practical utility in real-world clinical settings. The appeal of the qSOFA score lies in its simplicity, as it requires no laboratory testing and can be rapidly applied at the bedside. This makes it potentially valuable in resource-limited settings for early risk stratification, timely interventions, and communicating prognosis to patients and families.

In our study, the mortality rate at discharge was 22%, with a 28-day post-discharge mortality rate of 23.07%. These figures are significantly lower than those reported in previous Indian studies, where mortality rates reached 51.6% and 63.6%, as seen in studies by Shankar et al. and Sinha et al. (4,5), likely reflecting improved intensive care services and early interventions in our cohort. The performance of the SOFA score in predicting mortality was superior to that of qSOFA in both in-hospital and post-discharge settings. A SOFA score >11 showed high sensitivity (81.8%) and specificity (97.4%) at discharge and similarly high predictive accuracy at 28 days (sensitivity 77.78%, specificity 100%). These findings are consistent with the results of Ferreira et al (6), who demonstrated that higher SOFA scores were closely linked to increased ICU mortality. In contrast, the qSOFA score showed a lower sensitivity of 63.6% and specificity of 56.4% at discharge, though its 28-day mortality predictive sensitivity matched SOFA at 77.78%, albeit with a lower specificity (66.7%). This aligns with studies by Raith et al(7) and Freund et al(8), which suggested that while qSOFA is a useful screening tool, it may not be as robust as SOFA in predicting outcomes.

Area Under the Receiver Operating Characteristic (AUROC) analysis further supported these observations, with SOFA consistently outperforming qSOFA in mortality prediction. Nevertheless, the comparable sensitivity of qSOFA at 28 days suggests that it remains valuable for initial triage and rapid clinical decisions, particularly when lab data are unavailable. In conclusion, while SOFA remains the more accurate tool for mortality prediction in sepsis, qSOFA serves as a practical alternative for early identification and management, especially in emergency or resource-limited contexts.

In conclusion, while the qSOFA score demonstrated moderate sensitivity in predicting mortality at discharge (63.6%) and at 28-day follow-up (70%), the SOFA score proved to be more reliable, with 81.82% of patients who died at discharge and 77.78% who died post-discharge having a SOFA score above 11. These findings highlight that although qSOFA can be a useful bedside tool for early assessment and initiation of treatment in sepsis, especially in settings without immediate access to laboratory results, the SOFA score remains the most accurate and robust predictor of mortality outcomes in sepsis patients.

LIMITATION: This study has several limitations, including a small sample size that may affect the reliability and generalizability of the findings. Being conducted in a single tertiary care center in South India, the results may not reflect the broader national scenario. The post-discharge follow-up period was relatively short, potentially missing long-term outcomes, and the specific causes of mortality in sepsis could not be clearly determined. Additionally, follow-up for many patients was conducted via telephone due to geographic constraints, which may have limited the accuracy and completeness of follow-up data.

1. Singer M, et al. (2016). The Third International Consensus Definitions for Sepsis and Septic Shock (Sepsis-3). JAMA, 315(8), 801–810.
2. Vincent JL, et al. (1996). The SOFA (Sepsis-related Organ Failure Assessment) score to describe organ dysfunction/failure. Intensive Care Med, 22(7), 707–710.
3. Seymour CW, et al. (2016). Assessment of Clinical Criteria for Sepsis: For the Third International Consensus Definitions for Sepsis and Septic Shock (Sepsis-3). JAMA, 315(8), 762–774.
4. Shankar-Hari M, Phillips GS, Levy ML, et al. Developing a New Definition and Assessing New Clinical Criteria for Septic Shock. JAMA. 2016;315(8):775-787.
5. Sinha S, Ray B, Patnaik R, et al. Predictors of mortality in adult patients with sepsis in a tertiary care hospital. Journal of Global Infectious Diseases. 2015;7(2):54–58.
6. Ferreira FL, Bota DP, Bross A, Mélot C, Vincent JL. Serial Evaluation of the SOFA Score to Predict Outcome in Critically Ill Patients. JAMA. 2001;286(14):1754–1758.
7. Raith EP, Udy AA, Bailey M, et al. Prognostic Accuracy of the SOFA Score, SIRS Criteria, and qSOFA Score for In-Hospital Mortality Among Adults With Suspected Infection Admitted to the Intensive Care Unit. JAMA. 2017;317(3):290–300.
8. Freund Y, Lemachatti N, Krastinova E, et al. Prognostic Accuracy of Sepsis-3 Criteria for In-Hospital Mortality Among Patients With Suspected Infection Presenting to the Emergency Department. JAMA. 2017;317(3):301–308.