Systemic Inflammatory Index Is a Novel Predictor of Intubation Requirement and Mortality after SARS-CoV-2 Infection

Abstract

Coronavirus disease 2019 (COVID-19), with an increasing number of deaths worldwide, has created a tragic global health and economic emergency. The disease, caused by severe acute respiratory syndrome coronavirus 2019 (SARS-CoV-19), is a multi-system inflammatory disease with many of COVID-19-positive patients requiring intensive medical care due to multi-organ failures. Biomarkers to reliably predict the patient’s clinical cause of the virus infection, ideally, to be applied in point of care testing or through routine diagnostic approaches, are highly needed. We aimed to probe if routinely assessed clinical lab values can predict the severity of the COVID-19 course. Therefore, we have retrospectively analyzed on admission laboratory findings in 224 consecutive patients from four hospitals and show that systemic immune inflammation index (SII) is a potent marker for predicting the requirement for invasive ventilator support and for worse clinical outcome of the infected patient. Patients’ survival and severity of SARS-CoV-2 infection could reliably be predicted at admission by calculating the systemic inflammatory index of individual blood values. We advocate this approach to be a feasible and easy-to-implement assay that may be particularly useful to improve patient management during high influx crisis. We believe with this work to contribute to improving infrastructure availability and case management associated with COVID-19 pandemic hurdles.

Can prognostic nutritional index and systemic immune‐inflammatory index predict disease severity in COVID‐19?

“…16,17 However, there are a few studies investigating the predictive role of SII in the prognosis of COVID-19. 20,33 In those studies, the SII levels were high in patients who died at the hospital and who developed ARDS. In our study, SII was significantly specificity for prediction of the disease severity in COVID-19.…”

Comparison of Systemic Immune-Inflammation Index (SII), Early Warning Score (ANDC) and Prognostic Nutritional Index (PNI) in Hospitalized Patients with Malignancy, and Their Influence on Mortality from COVID-19

“…Their retrospective study, including 119 patients showed that higher SII values were associated with increased mortality rate [14]. Another retrospective study yielded similar results for SII indicating that it was a powerful marker for calling for an invasive ventilator support and preparing for a worse clinical outcome for the COVID-19 patients [13]. In our study, NLR, PLR, MLR and SII did not differ in two groups which were matched according to the age, gender and comorbidities using propensity score matching.…”

Comparison of systemic immune-inflammation index (SII), early warning score (ANDC) and prognostic nutritional index (PNI) in hospitalized patients with malignancy, and their influence on mortality from COVID-19

“…Their retrospective study, including 119 patients showed that higher SII values were associated with increased mortality rate. Another retrospective study yielded similar results for SII indicating that it was a powerful marker for calling for an invasive ventilator support and preparing for a worse clinical outcome for the COVID-19 patients [ 13 ]. In our study, NLR, PLR, MLR and SII did not differ in two groups which were matched according to the age, gender and comorbidities using propensity score matching.…”

“…Several studies have reported that the SII is associated with the prognosis of patients with malignancies. However, few studies demonstrated that SII index could have helped in predicting the clinical progression of the patient with COVID-19 [ 13 , 14 ].…”