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Published on: October 23, 2020
Development and Validation of a Survival Calculator for Hospitalized Patients with COVID-19
Insights
A new calculator predicts 7-day survival in hospitalized coronavirus disease 2019 (COVID-19) patients using six routine factors. The NOCOS Calculator (Northwell COVID-19 Survival) aids in assessing patient outcomes.
Area of Science:
- Critical Care Medicine
- Infectious Diseases
- Biostatistics
Background:
- Predicting severe coronavirus disease 2019 (COVID-19) outcomes is crucial for patient management.
- Existing survival calculators lack generalizability and simplicity, particularly for US patient populations.
- A need exists for a validated clinical tool to estimate short-term survival in hospitalized COVID-19 patients.
Approach:
- A retrospective and prospective cohort study was conducted across thirteen acute care hospitals in the New York City area.
- Data from 11,095 adult patients hospitalized with confirmed COVID-19 between March and May 2020 were analyzed.
- Least Absolute Shrinkage and Selection Operator (LASSO) regression identified optimal predictors from demographic, laboratory, and clinical data.
Key Points:
- The NOCOS Calculator identifies six key predictors of 7-day survival: serum blood urea nitrogen, age, absolute neutrophil count, red cell distribution width, oxygen saturation, and serum sodium.
- The calculator demonstrated strong performance with area under the curve (AUC) values of 0.86 for internal validation, 0.82 for prospective validation, and 0.82 for external validation.
- Routine factors available at hospital admission are utilized, simplifying clinical application.
Conclusions:
- The NOCOS Calculator provides a simple and generalizable tool for predicting 7-day survival in hospitalized COVID-19 patients.
- The calculator is publicly accessible, facilitating its use in clinical practice and research.
- This tool can aid clinicians in risk stratification and management decisions for COVID-19 patients.
Background:
Chinese studies reported predictors of severe disease and mortality associated with coronavirus disease 2019 (COVID-19). A generalizable and simple survival calculator based on data from US patients hospitalized with COVID-19 has not yet been introduced.
Objective:
Develop and validate a clinical tool to predict 7-day survival in patients hospitalized with COVID-19.
Design:
Retrospective and prospective cohort study.
Setting:
Thirteen acute care hospitals in the New York City area.
Participants:
Adult patients hospitalized with a confirmed diagnosis of COVID-19. The development and internal validation cohort included patients hospitalized between March 1 and May 6, 2020. The external validation cohort included patients hospitalized between March 1 and May 5, 2020.
Measurements:
Demographic, laboratory, clinical, and outcome data were extracted from the electronic health record. Optimal predictors and performance were identified using least absolute shrinkage and selection operator (LASSO) regression with receiver operating characteristic curves and measurements of area under the curve (AUC).
Results:
The development and internal validation cohort included 11 095 patients with a median age of 65 years [interquartile range (IQR) 54-77]. Overall 7-day survival was 89%. Serum blood urea nitrogen, age, absolute neutrophil count, red cell distribution width, oxygen saturation, and serum sodium were identified as the 6 optimal of 42 possible predictors of survival. These factors constitute the NOCOS (Northwell COVID-19 Survival) Calculator. Performance in the internal validation, prospective validation, and external validation were marked by AUCs of 0.86, 0.82, and 0.82, respectively.
Limitations:
All participants were hospitalized within the New York City area.
Conclusions:
The NOCOS Calculator uses 6 factors routinely available at hospital admission to predict 7-day survival for patients hospitalized with COVID-19. The calculator is publicly available at https://feinstein.northwell.edu/NOCOS.
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