Development and Validation of the RCOS Prognostic Index: A Bedside Multivariable Logistic Regression Model to Predict Hypoxaemia or Death in Patients with SARS-CoV-2 Infection

Gerardo Alvarez-Uria; Sumanth Gandra; Venkata R Gurram; Raghu P Reddy; Manoranjan Midde; Praveen Kumar; Ketty E Arce

doi:10.1155/2022/2360478

Development and Validation of the RCOS Prognostic Index: A Bedside Multivariable Logistic Regression Model to Predict Hypoxaemia or Death in Patients with SARS-CoV-2 Infection

Interdiscip Perspect Infect Dis. 2022 Apr 20:2022:2360478. doi: 10.1155/2022/2360478. eCollection 2022.

Authors

Gerardo Alvarez-Uria¹, Sumanth Gandra², Venkata R Gurram³, Raghu P Reddy⁴, Manoranjan Midde¹, Praveen Kumar⁵, Ketty E Arce⁶

Affiliations

¹ Department of Infectious Diseases, Rural Development Trust Hospital, Bathalapalli, AP, India.
² Division of Infectious Diseases, Department of Internal Medicine, Washington University School of Medicine, St. Louis, Missouri, USA.
³ Department of General Medicine, Rural Development Trust Hospital, Bathalapalli, AP, India.
⁴ Department of Microbiology, Rural Development Trust Hospital, Bathalapalli, AP, India.
⁵ Department of Orthopaedics, Rural Development Trust Hospital, Bathalapalli, AP, India.
⁶ Department of Emergency Medicine, Rural Development Trust Hospital, Bathalapalli, AP, India.

Abstract

Introduction: Previous COVID-19 prognostic models have been developed in hospital settings and are not applicable to COVID-19 cases in the general population. There is an urgent need for prognostic scores aimed to identify patients at high risk of complications at the time of COVID-19 diagnosis.

Methods: The RDT COVID-19 Observational Study (RCOS) collected clinical data from patients with COVID-19 admitted regardless of the severity of their symptoms in a general hospital in India. We aimed to develop and validate a simple bedside prognostic score to predict the risk of hypoxaemia or death.

Results: 4035 patients were included in the development cohort and 2046 in the validation cohort. The primary outcome occurred in 961 (23.8%) and 548 (26.8%) patients in the development and validation cohorts, respectively. The final model included 12 variables: age, systolic blood pressure, heart rate, respiratory rate, aspartate transaminase, lactate dehydrogenase, urea, C-reactive protein, sodium, lymphocyte count, neutrophil count, and neutrophil/lymphocyte ratio. In the validation cohort, the area under the receiver operating characteristic curve (AUROCC) was 0.907 (95% CI, 0.892-0.922), and the Brier Score was 0.098. The decision curve analysis showed good clinical utility in hypothetical scenarios where the admission of patients was decided according to the prognostic index. When the prognostic index was used to predict mortality in the validation cohort, the AUROCC was 0.947 (95% CI, 0.925-0.97) and the Brier score was 0.0188.

Conclusions: The RCOS prognostic index could help improve the decision making in the current COVID-19 pandemic, especially in resource-limited settings with poor healthcare infrastructure such as India. However, implementation in other settings is needed to cross-validate and verify our findings.