Hemogram-derived ratios as prognostic markers of ICU admission in COVID-19

Abstract

Background The vast impact of COVID-19 call for the identification of clinical parameter that can help predict a torpid evolution. Among these, endothelial injury has been proposed as one of the main pathophysiological mechanisms underlying the disease, promoting a hyperinflammatory and prothrombotic state leading to worse clinical outcomes. Leukocytes and platelets play a key role in inflammation and thrombogenesis, hence the objective of the current study was to study whether neutrophil-to-lymphocyte ratio (NLR), platelets-to-lymphocyte ratio (PLR), the systemic immune-inflammation index (SII) as well as the new parameter neutrophil-to-platelet ratio (NPR), could help identify patients who at risk of admission at Intensive Care Units. Methods A retrospective observational study was performed at HM Hospitales including electronic health records from 2245 patients admitted due to COVID-19 from March 1 to June 10, 2020. Patients were divided into two groups, admitted at ICU or not. Results Patients who were admitted at the ICU had significantly higher values in all hemogram-derived ratios at the moment of hospital admission compared to those who did not need ICU admission. Specifically, we found significant differences in NLR (6.9 [4–11.7] vs 4.1 [2.6–7.6], p < 0.0001), PLR (2 [1.4–3.3] vs 1.9 [1.3–2.9], p = 0.023), NPR (3 [2.1–4.2] vs 2.3 [1.6–3.2], p < 0.0001) and SII (13 [6.5–25.7] vs 9 [4.9–17.5], p < 0.0001) compared to those who did not require ICU admission. After multivariable logistic regression models, NPR was the hemogram-derived ratio with the highest predictive value of ICU admission, (OR 1.11 (95% CI: 0.98–1.22, p = 0.055). Conclusions Simple, hemogram-derived ratios obtained from early hemogram at hospital admission, especially the novelty NPR, have shown to be useful predictors of risk of ICU admission in patients hospitalized due to COVID-19.

Dynamic Changes of the Neutrophil-to-Lymphocyte Ratio, Systemic Inflammation Index, and Derived Neutrophil-to-Lymphocyte Ratio Independently Predict Invasive Mechanical Ventilation Need and Death in Critically Ill COVID-19 Patients

“…NLR is the most studied hematological index in COVID-19 patients and higher values were correlated with disease severity and progression [ 12 , 13 , 23 , 24 , 25 ], death [ 13 , 14 , 22 , 24 , 26 ], and treatment response [ 27 ]. Our observations are in agreement for NLR but also for PLR, MLR, SII, and dNLR and are correlated with results from other studies [ 11 , 12 , 13 , 14 , 15 , 23 , 24 , 25 , 26 , 28 , 29 , 30 , 31 ]. In our study, dynamic changes of these hematological indices had stronger correlations and better predictive value for progression to IMV in non-intubated patients and death compared with ICU admission values.…”

“…In our study, this was highlighted by the change in the discriminative power (value of AUC) of these indices over time. AUC values for the derived hematological indices, even the ICU admission values, are roughly in line with the AUC reported in other studies [ 12 , 15 , 23 , 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 ], but different cut-off values were taken. For example, the cut-off value range for NLR as a predictor for disease severity or death is very wide—from 3.3 to 15.2 [ 12 , 15 , 24 , 27 , 32 ]—making it difficult to establish a final cut-off value.…”

The effects of antihypertensive medications on severity and outcomes of hypertensive patients with COVID-19

“…The results of various studies have shown a link between values of blood factors with high blood pressure [ 29 – 31 ] and COVID-19 [ 32 ]. Meanwhile, these factors can be considered as predictors of hypertension [ 33 ] or severity of COVID-19 [ 34 ].…”

Platelet‐derived immuno‐inflammatory indices show best performance in early prediction of COVID‐19 progression

“…Another research revealed that neutrophil‐to‐platelet ratio (NPR) had the highest predictive value at ICU admission among COVID‐19 patients in multivariable logistic regression models with NLR, PLR, and SII. 38 Similarly, a study by López‐Escobar et al 8 ( n = 2808) showed NLR and NPR to be significantly and independently associated with in‐hospital mortality of COVID‐19 patients in complex adjusted multivariable regression models.…”