Performance of CURB-65 and ISARIC 4C mortality scores for hospitalized patients with confirmed COVID-19 infection in Saudi Arabia

Comparison of the Predictive Capacity of Oxygenation Parameters, Oxygenation Indices, and CURB-65 to Mortality, Mechanical Ventilation, and Vasopressor Support in Community-Acquired Pneumonia at Different Altitudes

Background: Populations residing at high altitudes display distinct physiological adaptations that are essential for understanding respiratory diseases. However, there is limited research on how these adaptations affect the assessment and prognosis of community-acquired pneumonia (CAP). Methods: A prognostic validation nested within a retrospective cohort was conducted on subjects with pneumonia admitted to two high-complexity institutions in Colombia at different altitudes above sea level. The receiver operating characteristic (ROC) curves were calculated for SaO2, PaO2, SpO2, A-a O2 gradient, a-A index, PaO2/FiO2, SpO2/FiO2, and the CURB-65 score to predict 30-day mortality, requirement for invasive mechanical ventilation (IMV), and need for vasopressor support. Results: 3467 were selected for analysis, with 73.7% (2557/3467) residing at high altitudes and 26.2% (910/3467) at low altitudes. The CURB-65 score  ≥ 2 showed a performance in predicting mortality of 0.707 (95% CI: 0.653-0.761; p < 0.001) at low altitudes and 0.737 (95% CI: 0.709-0.765; p < 0.001) at high altitudes. The PaO2/FiO2 ≤ 300 showed a performance in predicting the need for IMV and vasopressor support of 0.734 (95% CI: 0.685-0.783; p < 0.001) and 0.724 (0.674-0.775; p < 0.001) at high altitudes, respectively. The SpO2/FiO2 ≤ 350 showed a performance in predicting the need for IMV of 0.679 (0.507-0.85; p < 0.001) at low altitudes. The A-a O2 gradient ≥ 10 showed a performance in predicting the need for vasopressor support of 0.686 (95% CI: 0.537-0.835; p=0.06) at low altitudes. Conclusion: In patients with CAP at altitudes above 2500 m above sea level, PaO2/FiO2, SpO2/FiO2, and the A-a O2 gradient show a greater predictive capacity for 30-day mortality, need for IMV, and vasopressor requirements. The CURB-65 score showed a good predictive performance.

The SpO2/FiO2 Ratio Combined with Prognostic Scores for Pneumonia and COVID-19 Increases Their Accuracy in Predicting Mortality of COVID-19 Patients

Background: Identifying high-risk COVID-19 patients is critical for emergency department decision-making. Our study's primary objective was to identify new independent predictors of mortality and their predictive utility in combination with traditional pneumonia risk assessment scores and new risk scores for COVID-19 developed during the pandemic. Methods: A retrospective study was performed in two Italian University Hospitals. A multivariable logistic model was used to locate independent parameters associated with mortality. Results: Age, PaO2/FiO2, and SpO2/FiO2 ratios were found to be independent parameters associated with mortality. This study found that the Pneumonia Severity Index (PSI) was superior to many of the risk scores developed during the pandemic, for example, the International Severe Acute Respiratory Infection Consortium Coronavirus Clinical Characterisation Consortium (ISARIC 4C) (AUC 0.845 vs. 0.687, p < 0.001), and to many of the risk scores already in use, for example, the National Early Warning Score 2 (NEWS2) (AUC 0.845 vs. 0.589, p < 0.001). Furthermore, our study found that the Pneumonia Severity Index had a similar performance to other risk scores, such as CRB-65 (AUC 0.845 vs. 0.823, p = 0.294). Combining the PaO2/FiO2 or SpO2/FiO2 ratios with the risk scores analyzed improved the prognostic accuracy. Conclusions: Adding the SpO2/FiO2 ratio to the traditional, validated, and already internationally known pre-pandemic prognostic scores seems to be a valid and rapid alternative to the need for developing new prognostic scores. Future research should focus on integrating these markers into existing pneumonia scores to improve their prognostic accuracy.

Utility of the 4C ISARIC mortality score in hospitalized COVID-19 patients at a large tertiary Saudi Arabian center

Background

The International Severe Acute Respiratory and Emerging Infections Consortium (ISARIC) 4C mortality score has been used before as a valuable tool for predicting mortality in COVID-19 patients. We aimed to address the utility of the 4C score in a well-defined Saudi population with COVID-19 admitted to a large tertiary referral hospital in Saudi Arabia.

Methods

A retrospective study was conducted that included all adults COVID‑19 patients admitted to the Armed Forces Hospital Southern Region (AFHSR), between January 2021 and September 2022. The receiver operating characteristic (ROC) curve depicted the diagnostic performance of the 4C Score for mortality prediction.

Results

A total of 1,853 patients were enrolled. The ROC curve of the 4C score had an area under the curve of 0.73 (95% CI: 0.702-0.758), p<0.001. The sensitivity and specificity with scores >8 were 80% and 58%, respectively, the positive and negative predictive values were 28% and 93%, respectively. Three hundred and sixteen (17.1%), 638 (34.4%), 814 (43.9%), and 85 (4.6%) patients had low, intermediate, high, and very high values, respectively. There were significant differences between survivors and non-survivors with regard to all variables used in the calculation of the 4C score. Multivariable logistic regression analysis revealed that all components of the 4C score, except gender and O2 saturation, were independent significant predictors of mortality.

Conclusions

Our data support previous international and Saudi studies that the 4C mortality score is a reliable tool with good sensitivity and specificity in the mortality prediction of COVID-19 patients. All components of the 4C score, except gender and O2 saturation, were independent significant predictors of mortality. Within the 4C score, odds ratios increased proportionately with an increase in the score value. Future multi-center prospective studies are warranted.