Vaccination Status and Number of Vaccine Doses Are Independently Associated with the PaO2/FiO2 Ratio on Admission in Hospitalized COVID-19 Patients.

INTRODUCTION: Coronavirus Disease-19 (COVID-19) vaccines reduce the risk of severe disease and mortality. However, the association between vaccination status and number of doses and the PaO2/FiO2 ratio, a clinical measure of hypoxemia associated with an increased risk of intensive care treatment and mortality, has not been investigated. METHODS: We retrospectively assessed a consecutive series of 116 patients admitted to hospital with a primary diagnosis of COVID-19 between January and April 2022. Demographic, clinical, and laboratory data were collected within 24 h from admission. RESULTS: There was a significant positive relationship between the number of vaccine doses and the PaO2/FiO2 ratio (r = 0.223, p = 0.012). This association remained significant after adjusting for confounders. Vaccinated patients had significantly higher PaO2/FiO2 ratios than the unvaccinated (median: 250; IQR: 195-309 vs. 200; IQR: 156-257, p = 0.013). CONCLUSION: These results highlight the importance of the number of vaccine doses received in reducing the degree of hypoxia on admission in hospitalized COVID-19 patients.

Comparison of Clinical Features, Complete Blood Count Parameters, and Outcomes between Two Distinct Waves of COVID-19: A Monocentric Report from Italy.

BACKGROUND: Since the beginning of the SARS-CoV-2 pandemic, the ability to predict the trajectory of the disease has represented a major challenge for clinicians. There is recent evidence that complete blood cell count (CBC)-derived inflammation indexes have predictive value in COVID-19. We aimed to describe any changes in the clinical features, CBC-derived ratios, and outcomes of patients admitted to our hospital across two temporally distinct waves. METHODS: We retrospectively assessed and compared the clinical characteristics and blood cell count values of patients hospitalized during the second and fourth waves of COVID-19, and explored any outcome differences in terms of the level of respiratory support required and transfer to intensive care. RESULTS: We observed that fourth-wave patients were older, less male-predominant, and carried more comorbidities compared to the second-wave patients but, nevertheless, experienced more favorable outcomes. A strong internal correlation was documented for both waves between outcomes and CBC-derived ratios, with the fourth-wave cases displaying lower admission values of the neutrophil-to-lymphocyte ratio (NLR), derived NLR (dNLR), platelet-to-lymphocyte ratio (PLR), and systemic inflammation index (SII). No significant differences were found for lymphocyte-to-monocyte ratio (LMR), systemic inflammation response index (SIRI), and aggregate index of systemic inflammation (AISI). CONCLUSIONS: We observed that both admission values of CBC-derived indexes and adverse respiratory outcomes decreased from the second to the fourth wave of COVID-19. These data represent a contribution to the existing knowledge on the role of CBC-derived indexes as a potential tool to help clinicians to quickly differentiate in-hospital patients at increased risk of serious illness and death.

A systematic review and meta-analysis of the association between the neutrophil, lymphocyte, and platelet count, neutrophil-to-lymphocyte ratio, and platelet-to-lymphocyte ratio and COVID-19 progression and mortality.

BACKGROUND AND AIMS: Severe manifestations of coronavirus disease 2019 (COVID-19) are associated with alterations in blood cells that regulate immunity, inflammation, and hemostasis. We conducted an updated systematic review and meta-analysis of the association between the neutrophil, lymphocyte, and platelet count, neutrophil-to-lymphocyte ratio (NLR), and platelet-to-lymphocyte ratio (PLR), and COVID-19 progression and mortality. METHODS: A systematic literature search was conducted in PubMed, Web of Science, and Scopus for studies published between January 2020 and June 2022. RESULTS: In 71 studies reporting the investigated parameters within 48 hours of admission, higher NLR (HR 1.21, 95% CI 1.16 to 1.27, p < 0.0001), relative neutrophilia (HR 1.62, 95% CI 1.46 to 1.80, p < 0.0001), relative lymphopenia (HR 1.62, 95% CI 1.27 to 2.08, p < 0.001), and relative thrombocytopenia (HR 1.74, 95% CI 1.36 to 2.22, p < 0.001), but not PLR (p = 0.11), were significantly associated with disease progression and mortality. Between-study heterogeneity was large-to-extreme. The magnitude and direction of the effect size were not modified in sensitivity analysis. CONCLUSIONS: NLR and neutrophil, lymphocyte, and platelet count significantly discriminate COVID-19 patients with different progression and survival outcomes. (PROSPERO registration number: CRD42021267875).

Serum hydroxybutyrate dehydrogenase and COVID-19 severity and mortality: a systematic review and meta-analysis with meta-regression.

Alterations in cardiac and renal biomarkers have been reported in coronavirus disease 19 (COVID-19). We conducted a systematic review and meta-analysis to investigate serum concentrations of hydroxybutyrate dehydrogenase (HBDH), a combined marker of myocardial and renal injury, in hospitalized COVID-19 patients with different disease severity and survival status. We searched PubMed, Web of Science and Scopus, between December 2019 and April 2021, for studies reporting HBDH in COVID-19. Risk of bias was assessed using the Newcastle-Ottawa scale, publication bias was assessed with the Begg's and Egger's tests, and certainty of evidence was assessed using GRADE. In 22 studies in 15,019 COVID-19 patients, serum HBDH concentrations on admission were significantly higher in patients with high disease severity or non-survivor status when compared to patients with low severity or survivor status (standardized mean difference, SMD = 0.90, 95% CI 0.74 to 1.07, p < 0.001; moderate certainty of evidence). Extreme between-study heterogeneity was observed (I2 = 93.5%, p < 0.001). Sensitivity analysis, performed by sequentially removing each study and re-assessing the pooled estimates, showed that the magnitude and the direction of the effect size were not substantially modified. A significant publication bias was observed. In meta-regression, the SMD of HBDH concentrations was significantly associated with markers of inflammation, sepsis, liver damage, non-specific tissue damage, myocardial injury, and renal function. Higher HBDH concentrations were significantly associated with higher COVID-19 severity and mortality. This biomarker of cardiac and renal injury might be useful for risk stratification in COVID-19. (PROSPERO registration number: CRD42021258123).

The PaO2/FiO2 ratio on admission is independently associated with prolonged hospitalization in COVID-19 patients.

INTRODUCTION: The early identification of factors that predict the length of hospital stay (HS) in patients affected by coronavirus desease (COVID-19) might assist therapeutic decisions and patient flow management. METHODOLOGY: We collected, at the time of admission, routine clinical, laboratory, and imaging parameters of hypoxia, lung damage, inflammation, and organ dysfunction in a consecutive series of 50 COVID-19 patients admitted to the Respiratory Disease and Infectious Disease Units of the University Hospital of Sassari (North-Sardinia, Italy) and alive on discharge. RESULTS: Prolonged HS (PHS, >21 days) patients had significantly lower PaO2/FiO2 ratio and lymphocytes, and significantly higher Chest CT severity score, C-reactive protein (CRP) and lactic dehydrogenase (LDH) when compared to non-PHS patients. In univariate logistic regression, Chest CT severity score (OR = 1.1891, p = 0.007), intensity of care (OR = 2.1350, p = 0.022), PaO2/FiO2 ratio (OR = 0.9802, p = 0.007), CRP (OR = 1.0952, p = 0.042) and platelet to lymphocyte ratio (OR = 1.0039, p = 0.036) were significantly associated with PHS. However, in multivariate logistic regression, only the PaO2/FiO2 ratio remained significantly correlated with PHS (OR = 0.9164; 95% CI 0.8479-0.9904, p = 0.0275). In ROC curve analysis, using a threshold of 248, the PaO2/FiO2 ratio predicted PHS with sensitivity and specificity of 60% and 91%, respectively (AUC = 0.780, 95% CI 0.637-0.886 p = 0.002). CONCLUSIONS: The PaO2/FiO2 ratio on admission is independently associated with PHS in COVID-19 patients. Larger prospective studies are needed to confirm this finding.

Cholesterol and Triglyceride Concentrations, COVID-19 Severity, and Mortality: A Systematic Review and Meta-Analysis With Meta-Regression.

Lipid profile alterations have been observed in patients with coronavirus disease 2019 (COVID-19) in relation to disease severity and mortality. We conducted a systematic review and meta-analysis with meta-regression of studies reporting total, HDL, and LDL-cholesterol, and triglyceride concentrations in hospitalized patients with COVID-19. We searched PubMed, Web of Science and Scopus, between January 2020 and January 2021, for studies describing lipid concentrations, COVID-19 severity, and survival status (PROSPERO registration number: CRD42021253401). Twenty-two studies in 10,122 COVID-19 patients were included in the meta-analysis. Pooled results showed that hospitalized patients with severe disease or non-survivor status had significantly lower total cholesterol (standardized mean difference, SMD = -0.29, 95% CI -0.41 to -0.16, p < 0.001), LDL-cholesterol (SMD = -0.30, 95% CI -0.41 to -0.18, p < 0.001), and HDL-cholesterol (SMD = -0.44, 95% CI -0.62 to -0.26, p < 0.001), but not triglyceride (SMD = 0.04, 95% CI -0.10 to -0.19, p = 0.57), concentrations compared to patients with milder disease or survivor status during follow up. Between-study heterogeneity was large-to-extreme. In sensitivity analysis, the effect size of different lipid fractions was not affected when each study was in turn removed. The Begg's and Egger's t-tests did not show evidence of publication bias, except for studies investigating LDL-cholesterol. In meta-regression, significant associations were observed between the SMD of LDL-cholesterol and age and hypertension, and between the SMD of triglycerides and study endpoint and aspartate aminotransferase. In our systematic review and meta-analysis, lower total, HDL, and LDL-cholesterol, but not triglyceride, concentrations were significantly associated with COVID-19 severity and mortality. Cholesterol concentrations might be useful, in combination with other clinical and demographic variables, for risk stratification and monitoring in this group. Systematic Review Registration: PROSPERO registration number: CRD42021253401.

INR and COVID-19 severity and mortality: A systematic review with meta-analysis and meta-regression.

OBJECTIVES: D-dimer elevations, suggesting a pro-thrombotic state and coagulopathy, predict adverse outcomes in coronavirus disease 2019 (COVID-19). However, the clinical significance of other coagulation markers, particularly the international normalized ratio (INR), is not well established. We conducted a systematic review and meta-analysis of the INR in COVID-19. METHODS: A literature search was conducted in PubMed, Web of Science and Scopus, between January 2020 and February 2021, for studies reporting INR values, measures of COVID-19 severity, and mortality (PROSPERO registration number: CRD42021241468). RESULTS: Thirty-eight studies in 7440 COVID-19 patients with low disease severity or survivor status during follow up (50 â€‹% males, mean age 57 years) and 2331 with high severity or non-survivor status (60 â€‹% males, mean age 69 years) were identified. The INR was significantly prolonged in patients with severe disease or non-survivor status than in patients with mild disease or survivor status (standard mean difference, SMD, 0.60; 95 â€‹% confidence interval, CI 0.42 to 0.77; p â€‹< â€‹0.001). There was extreme between-study heterogeneity (I2 â€‹= â€‹90.2 â€‹%; p â€‹< â€‹0.001). Sensitivity analysis, performed by sequentially removing each study and re-assessing the pooled estimates, showed that the magnitude and direction of the effect size was not modified. The Begg's and Egger's t-tests did not show publication bias. In meta-regression, the SMD of the INR was significantly associated with C-reactive protein (p â€‹= â€‹0.048) and D-dimer (p â€‹= â€‹0.001). CONCLUSIONS: Prolonged INR values were significantly associated with COVID-19 severity and mortality. Both INR prolongation and D-dimer elevations can be useful in diagnosing COVID-19-associated coagulopathy and predicting clinical outcomes.

Cystatin C, COVID-19 severity and mortality: a systematic review and meta-analysis.

BACKGROUND: Combined markers of renal dysfunction and inflammation, e.g., cystatin C, might assist with risk stratification and clinical decisions in patients with coronavirus disease 19 (COVID-19). We conducted a systematic review and meta-analysis with meta-regression of serum cystatin C in COVID-19. METHODS: We searched PubMed, Web of Science and Scopus, between January 2020 and February 2021, for studies reporting serum cystatin C concentrations, measures of clinical severity and survival outcomes in hospitalized COVID-19 patients (PROSPERO registration number: CRD42021245295). RESULTS: Thirteen studies in 2510 COVID-19 patients, 1972 with low severity or survivor status and 538 with high severity or non-survivor status during follow up, were included in the meta-analysis. The pooled results showed that serum cystatin C concentrations were higher in patients with high disease severity or non-survivor status (standard mean deviation, SMD, 1.71, 95% CI 0.95 to 2.46, p < 0.001). Extreme between-study heterogeneity was observed (I2 = 97.5%, p < 0.001). Sensitivity analysis, performed by sequentially removing each study and re-assessing the pooled estimates, showed that the magnitude and direction of the effect size was not substantially modified. The Begg's and Egger's t tests did not show publication bias. In meta-regression, the SMD of serum cystatin C was not associated with age, proportion of males, C-reactive protein, neutrophils, lymphocytes, aspartate aminotransferase, alanine aminotransferase, albumin, creatinine, creatine kinase-MB, lactate dehydrogenase, and proportion of patients with diabetes or hypertension. CONCLUSIONS: Higher concentrations of serum cystatin C were associated with higher COVID-19 severity and mortality.

B-Type Natriuretic Peptide Concentrations, COVID-19 Severity, and Mortality: A Systematic Review and Meta-Analysis With Meta-Regression.

Alterations in cardiac biomarkers have been reported in patients with coronavirus disease 2019 (COVID-19) in relation to disease severity and mortality. We conducted a systematic review and meta-analysis with meta-regression of studies reporting B-type natriuretic peptide (BNP) or N-terminal proBNP (NT-proBNP) plasma concentrations in COVID-19. We searched PubMed, Web of Science, and Scopus, between January 2020 and 2021, for studies reporting BNP/NT-proBNP concentrations, measures of COVID-19 severity, and survival status (PROSPERO registration number: CRD42021239190). Forty-four studies in 18,856 COVID-19 patients were included in the meta-analysis and meta-regression. In pooled results, BNP/NT-proBNP concentrations were significantly higher in patients with high severity or non-survivor status when compared to patients with low severity or survivor status during follow up (SMD = 1.07, 95% CI: 0.89-1.24, and p < 0.001). We observed extreme between-study heterogeneity (I 2 = 93.9%, p < 0.001). In sensitivity analysis, the magnitude and the direction of the effect size were not substantially modified after sequentially removing individual studies and re-assessing the pooled estimates, (effect size range, 0.99 - 1.10). No publication bias was observed with the Begg's (p = 0.26) and Egger's (p = 0.40) t-tests. In meta-regression analysis, the SMD was significantly and positively associated with D-dimer (t = 2.22, p = 0.03), myoglobin (t = 2.40, p = 0.04), LDH (t = 2.38, p = 0.02), and procalcitonin (t = 2.56, p = 0.01) concentrations. Therefore, higher BNP/NT-proBNP plasma concentrations were significantly associated with severe disease and mortality in COVID-19 patients.

Serum CK-MB, COVID-19 severity and mortality: An updated systematic review and meta-analysis with meta-regression.

OBJECTIVES: We conducted a systematic review and meta-analysis with meta-regression of creatine kinase-MB (CK-MB), a biomarker of myocardial injury, in COVID-19 patients. METHODS: We searched PubMed, Web of Science and Scopus, for studies published between January 2020 and January 2021 that reported CK-MB, COVID-19 severity and mortality (PROSPERO registration number: CRD42021239657). RESULTS: Fifty-five studies in 11,791 COVID-19 patients were included in the meta-analysis. The pooled results showed that CK-MB concentrations were significantly higher in patients with high disease severity or non-survivor status than patients with low severity or survivor status (standardized mean difference, SMD, 0.81, 95% CI 0.61 to 1.01, p<0.001). The rate of patients with CK-MB values above the normal range was also significantly higher in the former than the latter (60/350 vs 98/1,780; RR â€‹= â€‹2.84, 95%CI 1.89 to 4.27, p<0.001; I2 â€‹= â€‹19.9, p â€‹= â€‹0.254). Extreme between-study heterogeneity was observed (I2 â€‹= â€‹93.4%, p<0.001). Sensitivity analysis, performed by sequentially removing each study and re-assessing the pooled estimates, showed that the magnitude and direction of the effect size was not modified (effect size range, 0.77 to 0.84). Begg's (p â€‹= â€‹0.50) and Egger's (p â€‹= â€‹0.86) t-tests did not show publication bias. In meta-regression analysis, the SMD was significantly and positively associated with the white blood count, aspartate aminotransferase, myoglobin, troponin, brain natriuretic peptide, lactate dehydrogenase, and D-dimer. CONCLUSIONS: Higher CK-MB concentrations were significantly associated with severe disease and mortality in COVID-19 patients. This biomarker of myocardial injury might be useful for risk stratification in this group.

Serum Complement C3 and C4 and COVID-19 Severity and Mortality: A Systematic Review and Meta-Analysis With Meta-Regression.

Activation of the complement system has been observed in coronavirus disease 19 (COVID-19). We conducted a systematic review and meta-analysis with meta-regression to investigate possible differences in the serum concentrations of two routinely measured complement components, C3 and C4, in COVID-19 patients with different severity and survival status. We searched PubMed, Web of Science and Scopus, between January 2020 and February 2021, for studies reporting serum complement C3 and C4, measures of COVID-19 severity, and survival. Eligibility criteria were a) reporting continuous data on serum C3 and C4 concentrations in COVID-19 patients, -b) investigating COVID-19 patients with different disease severity and/or survival status, c) adult patients, d) English language, e) ≥10 patients, and f) full-text available. Using a random-effects model, standardized mean differences (SMD) with 95% confidence intervals (CIs) were calculated to evaluate differences in serum C3 and C4 concentrations between COVID-19 patients with low vs. high severity or survivor vs. non-survivor status. Risk of bias was assessed using the Newcastle-Ottawa scale whereas publication bias was assessed with the Begg's and Egger's tests. Certainty of evidence was assessed using GRADE. Nineteen studies in 3,764 COVID-19 patients were included in the meta-analysis. Both C3 and C4 concentrations were significantly lower in patients with high disease severity or non-survivor status than patients with low severity or survivor status (C3 SMD=-0.40, 95% CI -0.60 to -0.21, p<0.001; C4 SMD=-0.29, 95% CI -0.49 to -0.09, p=0.005; moderate certainty of evidence). Extreme between-study heterogeneity was observed (C3, I2 = 82.1%; C4, I2 = 84.4%). Sensitivity analysis, performed by sequentially removing each study and re-assessing the pooled estimates, showed that the magnitude and direction of the effect size was not modified. There was no publication bias. In meta-regression, the SMD of C3 was significantly associated with white blood cell count, C-reactive protein (CRP), and pro-thrombin time, whereas the SMD of C4 was significantly associated with CRP, pro-thrombin time, D-dimer, and albumin. In conclusion, lower concentrations of C3 and C4, indicating complement activation, were significantly associated with higher COVID-19 severity and mortality. C3 and C4 might be useful to predict adverse clinical consequences in these patients. Systematic Review Registration: PROSPERO, Registration number: CRD42021239634.

Serum amyloid A concentrations, COVID-19 severity and mortality: An updated systematic review and meta-analysis.

BACKGROUND AND OBJECTIVES: An excessive inflammatory response in patients with coronavirus disease 2019 (COVID-19) is associated with high disease severity and mortality. Specific acute phase reactants might be useful for risk stratification. A systematic review and meta-analysis was conducted of studies on serum amyloid A (SAA) in patients with COVID-19. METHODS: The PubMed, Web of Science, and Scopus databases were searched, covering the period January 2020 to December 2020, for studies reporting SAA concentrations, COVID-19 severity, and survival status. RESULTS: Nineteen studies involving 5617 COVID-19 patients were included in the meta-analysis. Pooled results showed that SAA concentrations were significantly higher in patients with severe disease and non-survivors (standard mean difference (SMD) 1.20, 95% confidence interval 0.91-1.49, P < 0.001). Extreme between-study heterogeneity was observed (I2 = 92.4%, P < 0.001). In the sensitivity analysis, the effect size was not significantly affected when each study was removed in turn (range 1.10-1.29). The Begg test (P = 0.030), but not the Egger test (P = 0.385), revealed the presence of publication bias. Pooled SMD values were significantly and positively associated with sex (t = 2.20, P = 0.047) and aspartate aminotransferase (t = 3.44, P = 0.014). CONCLUSIONS: SAA concentrations were significantly and positively associated with higher COVID-19 severity and mortality. This acute phase reactant might assist with risk stratification and monitoring in this group.

Serum Prealbumin Concentrations, COVID-19 Severity, and Mortality: A Systematic Review and Meta-Analysis.

Excessive inflammation and malnutrition are associated with coronavirus disease 2019 (COVID-19) severity and mortality. Combined biomarkers of malnutrition and inflammation, such as serum prealbumin, might be particularly attractive for early risk stratification. We conducted a systematic review and meta-analysis of studies reporting serum prealbumin in patients with COVID-19. We searched PubMed, Web of Science and Scopus, between January and November 2020, for studies reporting data on serum prealbumin, COVID-19 severity, defined as severe illness, prolonged viral load, receiving mechanical ventilation or admitted to intensive care unit (ICU), and mortality. Nineteen studies in 4,616 COVID-19 patients were included in the meta-analysis. Pooled results showed that serum prealbumin concentrations were significantly lower in patients with severe disease and non-survivors (standard mean difference, SMD, -0.92, 95% CI, -1.10 to -0.74, P < 0.001). Extreme heterogeneity was observed (I 2 = 77.9%; P < 0.001). In sensitivity analysis, the effect size was not significantly affected when each study was in turn removed (range between -0.86 and -0.95). The Begg's (P = 0.06) and Egger's t-tests (P = 0.26) did not show publication bias. Pooled SMD values were significantly and negatively associated with age (t = -2.18, P = 0.045) and C-reactive protein (t = -3.85, P = 0.002). In our meta-analysis, lower serum prealbumin concentrations were significantly associated with COVID-19 severity and mortality. This combined marker of malnutrition and inflammation might assist with early risk stratification and management in this group.

Therapeutic Potential of Resveratrol in COVID-19-Associated Hemostatic Disorders.

Coagulation disorders, endotheliopathy and inflammation are the most common hallmarks in SARS-CoV-2 infection, largely determining COVID-19's outcome and severity. Dysfunctions of endothelial cells and platelets are tightly linked in contributing to the systemic inflammatory response that appears to be both a cause and a consequence of COVID-19-associated coagulation disorders and thrombotic events. Indeed, elevated levels of circulating inflammatory cytokines are often associated with abnormal coagulation parameters in COVID-19 patients. Although treatments with low molecular weight heparin (LMWH) have shown beneficial effects in decreasing patient mortality with severe COVID-19, additional therapeutic strategies are urgently needed. Utilizing the anti-inflammatory and anti-thrombotic properties of natural compounds may provide alternative therapeutic approaches to prevent or reduce the risk factors associated with pre-existing conditions and comorbidities that can worsen COVID-19 patients' outcomes. In this regard, resveratrol, a natural compound found in several plants and fruits such as grapes, blueberries and cranberries, may represent a promising coadjuvant for the prevention and treatment of COVID-19. By virtue of its anti-thrombotic and anti-inflammatory properties, resveratrol would be expected to lower COVID-19-associated mortality, which is well known to be increased by thrombosis and inflammation. This review analyzes and discusses resveratrol's ability to modulate vascular hemostasis at different levels targeting both primary hemostasis (interfering with platelet activation and aggregation) and secondary hemostasis (modulating factors involved in coagulation cascade).

Serum albumin concentrations are associated with disease severity and outcomes in coronavirus 19 disease (COVID-19): a systematic review and meta-analysis.

Coronavirus disease 2019 (COVID-19), an infectious disease caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is responsible for the most threatening pandemic in modern history. The aim of this systematic review and meta-analysis was to investigate the associations between serum albumin concentrations and COVID-19 disease severity and adverse outcomes. A systematic literature search was conducted in PubMed, from inception to October 30, 2020. Sixty-seven studies in 19,760 COVID-19 patients (6141 with severe disease or poor outcome) were selected for analysis. Pooled results showed that serum albumin concentrations were significantly lower in patients with severe disease or poor outcome (standard mean difference, SMD: - 0.99 g/L; 95% CI, - 1.11 to - 0.88, p < 0.001). In multivariate meta-regression analysis, age (t = - 2.13, p = 0.043), publication geographic area (t = 2.16, p = 0.040), white blood cell count (t = - 2.77, p = 0.008) and C-reactive protein (t = - 2.43, p = 0.019) were significant contributors of between-study variance. Therefore, lower serum albumin concentrations are significantly associated with disease severity and adverse outcomes in COVID-19 patients. The assessment of serum albumin concentrations might assist with early risk stratification and selection of appropriate care pathways in this group.

Red Blood Cell Distribution Width, Disease Severity, and Mortality in Hospitalized Patients with SARS-CoV-2 Infection: A Systematic Review and Meta-Analysis.

The identification of biomarkers predicting disease severity and outcomes is the focus of intense research in patients with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2 infection). Ideally, such biomarkers should be easily derivable from routine tests. We conducted a systematic review and meta-analysis of the predictive role of the red blood cell distribution width (RDW), a routine hematological test, in patients with SARS-CoV-2 infection. We searched the electronic databases PubMed, Web of Science and Scopus, from January 2020 to November 2020, for studies reporting data on the RDW and coronavirus disease 2019 (COVID-19) severity, defined as severe illness or admission to the intensive care unit (ICU), and mortality. Eleven studies in 4901 COVID-19 patients were selected for the meta-analysis. Pooled results showed that the RDW values were significantly higher in patients with severe disease and non-survivors (standard mean difference, SMD = 0.56, 95% CI 0.31 to 0.81, p < 0.001). Heterogeneity between studies was extreme (I2 = 80.6%; p < 0.001). In sensitivity analysis, the effect size was not modified when each study was in turn removed (effect size range, between 0.47 and 0.63). The Begg's (p = 0.53) and Egger's tests (p = 0.52) showed no evidence of publication bias. No significant correlations were observed between SMD and age, gender, whole blood count, end point, study geographic area, or design. Our meta-analysis showed that higher RDW values are significantly associated with COVID-19 severity and mortality. This routine parameter might assist with early risk stratification in patients with SARS-CoV-2 infection.

The Systemic Inflammation Index on Admission Predicts In-Hospital Mortality in COVID-19 Patients.

BACKGROUND: The rapid onset of a systemic pro-inflammatory state followed by acute respiratory distress syndrome is the leading cause of mortality in patients with COVID-19. We performed a retrospective observational study to explore the capacity of different complete blood cell count (CBC)-derived inflammation indexes to predict in-hospital mortality in this group. METHODS: The neutrophil to lymphocyte ratio (NLR), derived NLR (dNLR), platelet to lymphocyte ratio (PLR), mean platelet volume to platelet ratio (MPR), neutrophil to lymphocyte × platelet ratio (NLPR), monocyte to lymphocyte ratio (MLR), systemic inflammation response index (SIRI), systemic inflammation index (SII), and the aggregate index of systemic inflammation (AISI) were calculated on hospital admission in 119 patients with laboratory confirmed COVID-19. RESULTS: Non-survivors had significantly higher AISI, dNLR, NLPR, NLR, SII, and SIRI values when compared to survivors. Similarly, Kaplan-Meier survival curves showed significantly lower survival in patients with higher AISI, dNLR, MLR, NLPR, NLR, SII, and SIRI. However, after adjusting for confounders, only the SII remained significantly associated with survival (HR = 1.0001; 95% CI, 1.0000-1.0001, p = 0.029) in multivariate Cox regression analysis. CONCLUSIONS: The SII on admission independently predicts in-hospital mortality in COVID-19 patients and may assist with early risk stratification in this group.

The De Ritis ratio as prognostic biomarker of in-hospital mortality in COVID-19 patients.

Increased concentrations of serum aspartate transaminase (AST) and alanine transaminase (ALT) are common in COVID-19 patients. However, their capacity to predict mortality, particularly the AST/ALT ratio, commonly referred to as the De Ritis ratio, is unknown. We investigated the association between the De Ritis ratio on admission and in-hospital mortality in 105 consecutive patients with coronavirus disease of 2019 (COVID-19) admitted to three COVID-19 referral centres in Sardinia, Italy. The De Ritis ratio was significantly lower in survivors than nonsurvivors (median: 1.25; IQR: 0.91-1.64 vs 1.67; IQR: 1.38-1.97, P = .002) whilst there were no significant between-group differences in ALT and AST concentrations. In ROC curve analysis, the AUC value of the De Ritis ratio was 0.701 (95% CI 0.603-0.787, P = .0006) with sensitivity and specificity of 74% and 70%, respectively. Kaplan-Meier survival curves showed a significant association between the De Ritis ratio and mortality (logrank test P = .014). By contrast, no associations were observed between the ALT and AST concentrations and mortality (logrank test P = .83 and P = .62, respectively). In multivariate Cox regression analysis, the HR in patients with De Ritis ratios ≥1.63 (upper tertile of this parameter) remained significant after adjusting for age, gender, smoking status, cardiovascular disease, intensity of care, diabetes, respiratory diseases, malignancies and kidney disease (HR: 2.46, 95% CI 1.05-5.73, P = .037). Therefore, the De Ritis ratio on admission was significantly associated with in-hospital mortality in COVID-19 patients. Larger studies are required to confirm the capacity of this parameter to independently predict mortality in this group.

D-Dimer Concentrations and COVID-19 Severity: A Systematic Review and Meta-Analysis.

Coronavirus disease 2019 (COVID-19) is a recently described infectious disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Since late 2019, COVID-19 has rapidly spread in virtually all countries, imposing the adoption of significant lockdown and social distancing measures. The activation of the coagulation cascade is a common feature of disseminated intravascular coagulation and adverse clinical outcomes in COVID-19 patients. In this study, we conducted a meta-analysis aiming to investigate differences in serum D-dimer concentrations in patients with and without severe COVID-19 disease. An electronic search in Medline (PubMed), Scopus and Web of Science was performed with no language restrictions, and 13 articles were reporting on 1,807 patients (585, 32.4% with severe disease) were finally identified and included in the meta-analysis. The pooled results of all studies revealed that the D-dimer concentrations were significantly higher in patients with more severe COVID-19 (SMD: 0.91 mg/L; 95% CI, 0.75 to 1.07 mg/L, p < 0.0001). The heterogeneity was moderate (I2 = 46.5%; p = 0.033). Sensitivity analysis showed that the effect size was not modified when any single study was in turn removed (effect size range, 0.87 mg/L to 0.93 mg/L). The Begg's (p = 0.76) and Egger's tests (p = 0.38) showed no publication bias. In conclusion, our systematic review and meta-analysis showed that serum D-dimer concentrations in patients with severe COVID-19 are significantly higher when compared to those with non-severe forms.

Laboratory test alterations in patients with COVID-19 and non COVID-19 interstitial pneumonia: a preliminary report.

INTRODUCTION: Coronavirus disease 19 (COVID-19) is the greatest pandemic in modern history. Laboratory test alterations have been described in COVID-19 patients, but differences with other pneumonias have been poorly investigated to date, especially in Caucasian populations. The aim of this study was to investigate differences and prognostic potential of routine blood tests in a series of Italian patients with COVID-19 and non-COVID-19 interstitial pneumonia. METHODOLOGY: Clinical data and routine laboratory tests of a consecutive series of 30 COVID-19 patients and 30 age and sex matched patients with non COVID-19 interstitial pneumonia have been retrospectively collected. Differences in laboratory tests between patients with COVID-19 and non COVID-19 pneumonias have been investigated, as well as differences between COVID-19 survivors and non survivors. RESULTS: COVID-19 patients had lower white blood cells, monocytes, neutrophils, and higher platelet counts. In addition, COVID-19 patients showed higher mean platelet volume, lower C reactive protein concentrations, and higher De Ritis ratio. Combined blood cell indexes of systemic inflammation were significantly lower in COVID-19 patients. In further analysis of the COVID-19 group, the neutrophil count, neutrophil to lymphocyte ratio (NLR), derived NLR, systemic inflammation response index and De Ritis ratio, were significantly higher in non survivors than in survivors, while the number of platelets was significantly lower in non survivors. CONCLUSIONS: Our study showed several alterations in blood cell populations and indexes in patients with COVID-19 pneumonia in comparison with patients with non COVID-19 pneumonia. Some of these indexes showed promising prognostic abilities. Further studies are necessary to confirm these results.