Combined Blood Indexes of Systemic Inflammation as a Mirror to Admission to Intensive Care Unit in COVID-19 Patients: A Multicentric Study

Abstract

Background The Coronavirus 2019 is a pandemic that has spread worldwide, threatening human health. The main cause of death in patients with COVID-19 is a systemic pro-inflammatory mechanism that quickly progresses to acute respiratory distress syndrome. Hematological ratios as affordable indicators of inflammatory response were studied in COVID-19 patients. The study aimed to study the importance of the blood cell indexes of the systemic inflammatory response, as the Aggregate Index of Systemic Inflammation (AISI), neutrophils lymphocyte to platelet ratio (NLPR), systemic immune-inflammation index (SII) and, systemic inflammation response index (SIRI) in predicting intensive care unit (ICU) admission of COVID-19 patients. Methods 495 COVID-19 patients managed in four tertiary centers; divided into non-ICU and ICU groups. Results Total leucocyte count (TLC), AISI, NLPR, SII, and SIRI were more elevated in the ICU group (P < 0.001 for all except AMC P = 0.006), while this group had less absolute lymphocyte count (ALC) (P = 0.047). We estimated the optimal cut-off values of the hematological ratio; AISI (729), NLPR (0.0195), SII (1346), and SIRI (2.5). SII had the highest specificity (95.6%), while NLPR had the highest sensitivity (61.3%). Age, AISI, CRP, D-dimer, and oxygen aid were the independent predictors for ICU admission in COVID-19 in multivariate logistic regression. Conclusion AISI is a predictor for severity and ICU admission in COVID-19 patients, SII is a predictor of survival, while NLPR and SIRI have an additive role that needs further evaluation.

The Role of Inflammatory Parameters in the Prognosis of Patients with COVID-19

“…AISI, NLPR, SII, and SIRI were associated with admission to ICU in the study by Hamad et al (22). Similar to this study, NLRP sensitivity was the highest index (cut-off >0.0195, 61.3%) (22).…”

Chest CT Severity Score and Systemic Inflammatory Biomarkers as Predictors of the Need for Invasive Mechanical Ventilation and of COVID-19 Patients’ Mortality

“…Regarding hematological indices, NLR and SII have been analyzed in numerous articles published recently [ 19 , 22 , 23 , 56 , 65 , 66 ]. Thus, Moisa et al [ 56 ] demonstrated that a basal value of NLR > 11 (HR:4.6; 95% CI:2.80–7.56; p < 0.001), MLR >0.64 (HR:2.38; 95% CI:1.70–3.33; p < 0.001), and SII > 3700 (HR:2.44; 95% CI:1.68–3.54; p < 0.001) are independent prognostic factors of mortality for the 272 patients diagnosed with COVID-19 [ 56 ].…”

“…Similarly, Kudlinsky et al published an article in which they proved the prognostic impact of NLR > 11.57 ( p = 0.0008) and SII > 2058 ( p = 0.02) in COVID-19 patients’ death [ 65 ]. In a cohort study involving 411 COVID-19 patients, Regolo et al discovered a correlation between baseline NLR values greater than 11.38 and the necessity for ICU admission ( p < 0.0001) [ 19 ].…”

Neutrophil Counts, Neutrophil-to-Lymphocyte Ratio, and Systemic Inflammatory Response Index (SIRI) Predict Mortality after Off-Pump Coronary Artery Bypass Surgery

“…Most recently, Zinellu et al (2021) underlined its prognostic significance to predict poor outcomes in idiopathic pulmonary fibrosis [ 72 ]. Furthermore, Hamad and coworkers (2021) also studied its importance in patients suffering from COVID-19 [ 23 ]. Although it was significant in univariate analysis, like SII, it did not convey a sufficient prognostic value in the multivariate analysis.…”

“…Numerous novel inflammatory markers have been described that involve the systemic inflammatory response index (SIRI—the quotient of neutrophils and monocytes, divided by lymphocyte count), the aggregate index of systemic inflammation (AISI—the quotient of neutrophils, monocytes, and platelets, divided by lymphocyte count), and the systemic inflammatory index (SII), composed of the quotient of neutrophils and platelets divided by lymphocyte counts [ 23 ]. These three indices have been presented as possible mortality prognostic factors in different cardiovascular and non-cardiovascular diseases [ 24 , 25 , 26 , 27 , 28 ].…”