Basic host response parameters to classify mortality risk in COVID-19 and community-acquired pneumonia.

Improved phenotyping in pneumonia is necessary to strengthen risk assessment. Via a feasible and multidimensional approach with basic parameters, we aimed to evaluate the effect of host response at admission on severity stratification in COVID-19 and community-acquired pneumonia (CAP). Three COVID-19 and one CAP multicenter cohorts including hospitalized patients were recruited. Three easily available variables reflecting different pathophysiologic mechanisms-immune, inflammation, and respiratory-were selected (absolute lymphocyte count [ALC], C-reactive protein [CRP] and, SpO2/FiO2). In-hospital mortality and intensive care unit (ICU) admission were analyzed as outcomes. A multivariable, penalized maximum likelihood logistic regression was performed with ALC (< 724 lymphocytes/mm3), CRP (> 60 mg/L), and, SpO2/FiO2 (< 450). A total of 1452, 1222 and 462 patients were included in the three COVID-19 and 1292 in the CAP cohort for the analysis. Mortality ranged between 4 and 32% (0 to 3 abnormal biomarkers) and 0-9% in SARS-CoV-2 pneumonia and CAP, respectively. In the first COVID-19 cohort, adjusted for age and sex, we observed an increased odds ratio for in-hospital mortality in COVID-19 with elevated biomarkers altered (OR 1.8, 3, and 6.3 with 1, 2, and 3 abnormal biomarkers, respectively). The model had an AUROC of 0.83. Comparable findings were found for ICU admission, with an AUROC of 0.76. These results were confirmed in the other COVID-19 cohorts Similar OR trends were reported in the CAP cohort; however, results were not statistically significant. Assessing the host response via accessible biomarkers is a simple and rapidly applicable approach for pneumonia.

Treatment Failure and Clinical Stability in Severe Community-Acquired Pneumonia.

Treatment failure and clinical stability are important outcomes in community-acquired pneumonia (CAP). It is essential to know the causes and risk factors for treatment failure and delay in reaching clinical stability in CAP. The study of both as well as the associated underlying mechanisms and host response are key to improving outcomes in pneumonia.

Persistent Respiratory Failure and Re-Admission in Patients with Chronic Obstructive Pulmonary Disease Following Hospitalization for COVID-19.

Background: Chronic obstructive pulmonary disease (COPD) has been associated with worse clinical evolution/survival during a hospitalization for SARS-CoV2 (COVID-19). The objective of this study was to learn the situation of these patients at discharge as well as the risk of re-admission/mortality in the following 12 months. Methods: We carried out a subanalysis of the RECOVID registry. A multicenter, observational study that retrospectively collected data on severe acute COVID-19 episodes and follow-up visits for up to a year in survivors. The data collection protocol includes general demographic data, smoking, comorbidities, pharmacological treatment, infection severity, complications during hospitalization and required treatment. At discharge, resting oxygen saturation (SpO2), dyspnea according to the mMRC (modified Medical Research Council) scale and long-term oxygen therapy prescription were recorded. The follow-up database included the clinical management visits at 6 and 12 months, where re-admission and mortality were recorded. Results: A total of 2047 patients were included (5.6% had a COPD diagnosis). At discharge, patients with COPD had greater dyspnea and a greater need for prescription home oxygen. After adjusting for age, sex and Charlson comorbidity index, patients with COPD had a greater risk of hospital re-admission due to respiratory causes (HR 2.57 [1.35-4.89], p = 0.004), with no significant differences in survival. Conclusion: Patients with COPD who overcome a serious SARS-CoV2 infection show a worse clinical situation at discharge and a greater risk of re-admission for respiratory causes.

Is the long-term mortality similar in COVID-19 and community-acquired pneumonia?

Introduction: There are no data on the association of type of pneumonia and long-term mortality by the type of pneumonia (COVID-19 or community-acquired pneumonia [CAP]) on long-term mortality after an adjustment for potential confounding variables. We aimed to assess the type of pneumonia and risk factors for long-term mortality in patients who were hospitalized in conventional ward and later discharged. Methods: Retrospective analysis of two prospective and multicentre cohorts of hospitalized patients with COVID-19 and CAP. The main outcome under study was 1-year mortality in hospitalized patients in conventional ward and later discharged. We adjusted a Bayesian logistic regression model to assess associations between the type of pneumonia and 1-year mortality controlling for confounders. Results: The study included a total of 1,693 and 2,374 discharged patients in the COVID-19 and CAP cohorts, respectively. Of these, 1,525 (90.1%) and 2,249 (95%) patients underwent analysis. Until 1-year follow-up, 69 (4.5%) and 148 (6.6%) patients from the COVID-19 and CAP cohorts, respectively, died (p = 0.008). However, the Bayesian model showed a low probability of effect (PE) of finding relevant differences in long-term mortality between CAP and COVID-19 (odds ratio 1.127, 95% credibility interval 0.862-1.591; PE = 0.774). Conclusion: COVID-19 and CAP have similar long-term mortality after adjusting for potential confounders.

Endothelial Damage, Neutrophil Extracellular Traps and Platelet Activation in COVID-19 vs. Community-Acquired Pneumonia: A Case-Control Study.

COVID-19 has been a diagnostic and therapeutic challenge. It has marked a paradigm shift when considering other types of pneumonia etiology. We analyzed the biomarkers related to endothelial damage and immunothrombosis in COVID-19 in comparison to community-acquired pneumonia (CAP) through a case-control study of 358 patients with pneumonia (179 hospitalized with COVID-19 vs. 179 matched hospitalized with CAP). Endothelial damage markers (endothelin and proadrenomedullin), neutrophil extracellular traps (NETs) (citrullinated-3 histone, cell-free DNA), and platelet activation (soluble P-selectin) were measured. In-hospital and 1-year follow-up outcomes were evaluated. Endothelial damage, platelet activation, and NET biomarkers are significantly higher in CAP compared to COVID-19. In-hospital mortality in COVID-19 was higher compared to CAP whereas 1-year mortality and cardiovascular complications were higher in CAP. In the univariate analysis (OR 95% CIs), proADM and endothelin were associated with in-hospital mortality (proADM: CAP 3.210 [1.698-6.070], COVID-19 8.977 [3.413-23.609]; endothelin: CAP 1.014 [1.006-1.022], COVID-19 1.024 [1.014-1.034]), in-hospital CVE (proADM: CAP 1.623 [1.080-2.439], COVID-19 2.146 [1.186-3.882]; endothelin: CAP 1.005 [1.000-1.010], COVID-19 1.010 [1.003-1.018]), and 1-year mortality (proADM: CAP 2.590 [1.644-4.080], COVID-19 13.562 [4.872-37.751]; endothelin: CAP 1.008 [1.003-1.013], COVID-19 1.026 [1.016-1.037]). In conclusion, COVID-19 and CAP showed different expressions of endothelial damage and NETs. ProADM and endothelin are associated with short- and long-term mortality.

Neutrophil Extracellular Traps and Platelet Activation for Identifying Severe Episodes and Clinical Trajectories in COVID-19.

The role of NETs and platelet activation in COVID-19 is scarcely known. We aimed to evaluate the role of NETs (citrullinated histone H3 [CitH3], cell-free DNA [cfDNA]) and platelet activation markers (soluble CD40 ligand [CD40L] and P-selectin) in estimating the hazard of different clinical trajectories in patients with COVID-19. We performed a prospective study of 204 patients, categorized as outpatient, hospitalized and ICU-admitted. A multistate model was designed to estimate probabilities of clinical transitions across varying states, such as emergency department (ED) visit, discharge (outpatient), ward admission, ICU admission and death. Levels of cfDNA, CitH3 and P-selectin were associated with the severity of presentation and analytical parameters. The model showed an increased risk of higher levels of CitH3 and P-selectin for ED-to-ICU transitions (Hazard Ratio [HR]: 1.35 and 1.31, respectively), as well as an elevated risk of higher levels of P-selectin for ward-to-death transitions (HR: 1.09). Elevated levels of CitH3 (HR: 0.90), cfDNA (HR: 0.84) and P-selectin (HR: 0.91) decreased the probability of ward-to-discharge transitions. A similar trend existed for elevated levels of P-selectin and ICU-to-ward transitions (HR 0.40); In conclusion, increased NET and P-selectin levels are associated with more severe episodes and can prove useful in estimating different clinical trajectories.

Residual pulmonary infiltrates, symptoms and diffusion impairment at 1-year after severe COVID-19 infection have different associated factors.

INTRODUCTION: After severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pneumonia, patients may show lung sequelae on radiology and functional impairment at the 1-year follow-up. We aimed to describe the persistence of symptoms, radiological alterations, or reduced diffusing capacity of the lung for carbon monoxide (DLCO ) at 1-year follow-up in patients from the Spanish Registry RECOVID. METHODS: RECOVID collected symptom and radiological and functional lung tests data on hospitalized patients with coronavirus disease 2019 during the acute phase and at the 6- and 12-month follow-up visits. RESULTS: Of the 2500 enrolled survivors (90% admitted to the ward), 1874 had follow-up visits for up to a year. Of these, 42% continued to present with symptoms, 27% had radiological sequelae and 31% had reduced DLCO . Independently associated factors included female sex, asthma and the requirement for invasive or non-invasive mechanical ventilation. Complete radiological resolution was 72.2% at 12 months; associated factors with incomplete recovery were age, male sex, oxygen or respiratory support, corticosteroids and an initial SpO2 /FiO2 <450 or CURB-65 ≥2. Reduced DLCO was observed in 31% of patients at 12 months; associated factors were older age, female sex, smoking habit, SpO2 /FiO2 <450 and CURB-65 ≥2 and the requirement of respiratory support.At 12 months, a proportion of the asymptomatic patients showed reduced DLCO (9.5%), radiological findings (25%) or both (11%). CONCLUSIONS: The factors associated with symptom persistence, incomplete radiological resolution and DLCO <80% differed according to age, sex, comorbidities and respiratory support. The burden of symptoms, reduced DLCO and incomplete radiological resolution were considerable in patients with SARS-CoV-2 pneumonia at the 1-year follow-up after hospitalisation.

Early Recognition of Low-Risk SARS-CoV-2 Pneumonia: A Model Validated With Initial Data and Infectious Diseases Society of America/American Thoracic Society Minor Criteria.

BACKGROUND: A shortage of beds in ICUs and conventional wards during the COVID-19 pandemic led to a collapse of health care resources. RESEARCH QUESTION: Can admission data and minor criteria by the Infectious Diseases Society of America (IDSA) and the American Thoracic Society (ATS) help identify patients with low-risk SARS-CoV-2 pneumonia? STUDY DESIGN AND METHODS: This multicenter cohort study included 1,274 patients in a derivation cohort and 830 (first wave) and 754 (second wave) patients in two validation cohorts. A multinomial regression analysis was performed on the derivation cohort to compare the following patients: those admitted to the ward (assessed as low risk); those admitted to the ICU directly; those transferred to the ICU after general ward admission; and those who died. A regression analysis identified independent factors for low-risk pneumonia. The model was subsequently validated. RESULTS: In the derivation cohort, similarities existed among those either directly admitted or transferred to the ICU and those who died. These patients could, therefore, be merged into one group. Five independently associated factors were identified as being predictors of low risk (not dying and/or requiring ICU admission) (ORs, with 95% CIs): peripheral blood oxygen saturation/Fio2 > 450 (0.233; 0.149-0.364); < 3 IDSA/ATS minor criteria (0.231; 0.146-0.365); lymphocyte count > 723 cells/mL (0.539; 0.360-0.806); urea level < 40 mg/dL (0.651; 0.426-0.996); and C-reactive protein level < 60 mg/L (0.454; 0.285-0.724). The areas under the curve were 0.802 (0.769-0.835) in the derivation cohort, and 0.779 (0.742-0.816) and 0.801 (0.757-0.845) for the validation cohorts (first and second waves, respectively). INTERPRETATION: Initial biochemical findings and the application of < 3 IDSA/ATS minor criteria make early identification of low-risk SARS-CoV-2 pneumonia (approximately 80% of hospitalized patients) feasible. This scenario could facilitate and streamline health care resource allocation for patients with COVID-19.

Acute and sustained increase in endothelial biomarkers in COVID-19.

Endothelial injury is related to poor outcomes in respiratory infections yet little is known in relation to COVID-19. Performing a longitudinal analysis (on emergency department admission and post-hospitalisation follow-up), we evaluated endothelial damage via surrogate systemic endothelial biomarkers, that is, proadrenomedullin (proADM) and proendothelin, in patients with COVID-19. Higher proADM and/or proendothelin levels at baseline were associated with the most severe episodes and intensive care unit admission when compared with ward-admitted individuals and outpatients. Elevated levels of proADM or proendothelin at day 1 were associated with in-hospital mortality. High levels maintained after discharge were associated with reduced diffusing capacity.

Cardiovascular Events During and After Bronchiectasis Exacerbations and Long-term Mortality.

BACKGROUND: Population-based and retrospective studies have shown that risk for cardiovascular events such as arrythmias, ischemic episodes, or heart failure, increase during and after bronchiectasis exacerbations. RESEARCH QUESTION: What are the risk factors for cardiovascular events (CVE) during and after bronchiectasis exacerbations and their impact on mortality? STUDY DESIGN AND METHODS: This was a post hoc retrospective analysis of a prospective observational study of 250 patients with bronchiectasis at two tertiary care hospitals. Only the first exacerbation was considered for each patient, collecting demographic, comorbidity, and severity data. The main outcomes were the appearance of CVE and mortality. Risk factors for CVE were analyzed using a semi-competing risks model. RESULTS: During a median follow-up of 35 months, 74 (29.6%) patients had a CVE and 93 (37.2%) died. Semi-competing risk analysis indicated that age, arterial hypertension, COPD, and potentially severe exacerbations significantly increased the risk for developing CVE. Compared with patients without CVE, those with CVE had higher mortality. INTERPRETATION: Demographic factors and comorbidities are risk factors for the development of CVE after an acute exacerbation of bronchiectasis. The appearance of CVE worsens long-term prognosis.

Bacteraemic pneumococcal pneumonia and SARS-CoV-2 pneumonia: differences and similarities.

OBJECTIVE: To analyse differences in clinical presentation and outcome between bacteraemic pneumococcal community-acquired pneumonia (B-PCAP) and sSvere Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) pneumonia. METHODS: This observational multi-centre study was conducted on patients hospitalized with B-PCAP between 2000 and 2020 and SARS-CoV-2 pneumonia in 2020. Thirty-day survival, predictors of mortality, and intensive care unit (ICU) admission were compared. RESULTS: In total, 663 patients with B-PCAP and 1561 patients with SARS-CoV-2 pneumonia were included in this study. Patients with B-PCAP had more severe disease, a higher ICU admission rate and more complications. Patients with SARS-CoV-2 pneumonia had higher in-hospital mortality (10.8% vs 6.8%; P=0.004). Among patients admitted to the ICU, the need for invasive mechanical ventilation (69.7% vs 36.2%; P<0.001) and mortality were higher in patients with SARS-CoV-2 pneumonia. In patients with B-PCAP, the predictive model found associations between mortality and systemic complications (hyponatraemia, septic shock and neurological complications), lower respiratory reserve and tachypnoea; chest pain and purulent sputum were protective factors in these patients. In patients with SARS-CoV-2 pneumonia, mortality was associated with previous liver and cardiac disease, advanced age, altered mental status, tachypnoea, hypoxaemia, bilateral involvement, pleural effusion, septic shock, neutrophilia and high blood urea nitrogen; in contrast, ≥7 days of symptoms was a protective factor in these patients. In-hospital mortality occurred earlier in patients with B-PCAP. CONCLUSIONS: Although B-PCAP was associated with more severe disease and a higher ICU admission rate, the mortality rate was higher for SARS-CoV-2 pneumonia and deaths occurred later. New prognostic scales and more effective treatments are needed for patients with SARS-CoV-2 pneumonia.

Incidence, risk factors, and thrombotic load of pulmonary embolism in patients hospitalized for COVID-19 infection.

OBJECTIVE: To determine the incidence, characteristics, and risk factors of pulmonary embolism (PE) among patients hospitalized for COVID-19. PATIENTS AND METHODS: We performed a prospective observational study of a randomly selected cohort of consecutive patients hospitalized for COVID-19 infection between March 8, 2020 through April 25, 2020. All eligible patients underwent a computed tomography pulmonary angiography independently of their PE clinical suspicion and were pre-screened for a baseline elevated D-dimer level. RESULTS: 119 patients were randomly selected from the 372 admitted to one tertiary hospital in Valencia (Spain) for COVID-19 infection during the period of study. Seventy-three patients fulfilled both the inclusion criteria and none of the exclusion criteria and were finally included in the study. Despite a high level of pharmacological thromboprophylaxis (89%), the incidence of PE was 35.6% (95% confidence interval [CI], 29.6 to 41.6%), mostly with a peripheral location and low thrombotic load (Qanadli score 18.5%). Multivariate analysis showed that heart rate (Hazard Ratio [HR], 1.04), room-air oxygen saturation (spO2) (HR, 0.87), D-dimer (HR, 1.02), and C-reactive protein (CRP) levels (HR, 1.01) at the time of admission were independent predictors of incident PE during hospitalization. A risk score was constructed with these four variables showing a high predictive value of incident PE (AUC-ROC: 0.86; 95% CI: 0.80 to 0.93). CONCLUSIONS: Our findings confirmed a high incidence of PE in hospitalized COVID-19 patients. Heart rate, spO2, D-dimer, and CRP levels at admission were associated with higher rates of PE during hospitalization.

miR-146a is a pivotal regulator of neutrophil extracellular trap formation promoting thrombosis.

Neutrophil extracellular traps (NETs) induce a procoagulant response linking inflammation and thrombosis. Low levels of miR-146a, a brake of inflammatory response, are involved in higher risk for cardiovascular events, but the mechanisms explaining how miR-146a exerts its function remain largely undefined. The aim of this study was to explore the impact of miR-146a deficiency in NETosis both, in sterile and non-sterile models in vivo, and to inquire into the underlying mechanism. Two models of inflammation were performed: 1) Ldlr-/- mice transplanted with bone marrow from miR-146a-/- or wild type (WT) were fed high-fat diet, generating an atherosclerosis model; and 2) an acute inflammation model was generated by injecting lipopolysaccharide (LPS) (1 mg/Kg) into miR-146a-/- and WT mice. miR-146a deficiency increased NETosis in both models. Accordingly, miR-146a-/- mice showed significant reduced carotid occlusion time and elevated levels of NETs in thrombi following FeCl3-induced thrombosis. Infusion of DNAse I abolished arterial thrombosis in WT and miR-146a-/- mice. Interestingly, miR-146a deficient mice have aged, hyperreactive and pro-inflammatory neutrophils in circulation that are more prone to form NETs independently of the stimulus. Furthermore, we demonstrated that community acquired pneumonia (CAP) patients with reduced miR-146a levels associated with the T variant of the functional rs2431697, presented an increased risk for cardiovascular events due in part to an increased generation of NETs.

Viral RNA load in plasma is associated with critical illness and a dysregulated host response in COVID-19.

BACKGROUND: COVID-19 can course with respiratory and extrapulmonary disease. SARS-CoV-2 RNA is detected in respiratory samples but also in blood, stool and urine. Severe COVID-19 is characterized by a dysregulated host response to this virus. We studied whether viral RNAemia or viral RNA load in plasma is associated with severe COVID-19 and also to this dysregulated response. METHODS: A total of 250 patients with COVID-19 were recruited (50 outpatients, 100 hospitalized ward patients and 100 critically ill). Viral RNA detection and quantification in plasma was performed using droplet digital PCR, targeting the N1 and N2 regions of the SARS-CoV-2 nucleoprotein gene. The association between SARS-CoV-2 RNAemia and viral RNA load in plasma with severity was evaluated by multivariate logistic regression. Correlations between viral RNA load and biomarkers evidencing dysregulation of host response were evaluated by calculating the Spearman correlation coefficients. RESULTS: The frequency of viral RNAemia was higher in the critically ill patients (78%) compared to ward patients (27%) and outpatients (2%) (p < 0.001). Critical patients had higher viral RNA loads in plasma than non-critically ill patients, with non-survivors showing the highest values. When outpatients and ward patients were compared, viral RNAemia did not show significant associations in the multivariate analysis. In contrast, when ward patients were compared with ICU patients, both viral RNAemia and viral RNA load in plasma were associated with critical illness (OR [CI 95%], p): RNAemia (3.92 [1.183-12.968], 0.025), viral RNA load (N1) (1.962 [1.244-3.096], 0.004); viral RNA load (N2) (2.229 [1.382-3.595], 0.001). Viral RNA load in plasma correlated with higher levels of chemokines (CXCL10, CCL2), biomarkers indicative of a systemic inflammatory response (IL-6, CRP, ferritin), activation of NK cells (IL-15), endothelial dysfunction (VCAM-1, angiopoietin-2, ICAM-1), coagulation activation (D-Dimer and INR), tissue damage (LDH, GPT), neutrophil response (neutrophils counts, myeloperoxidase, GM-CSF) and immunodepression (PD-L1, IL-10, lymphopenia and monocytopenia). CONCLUSIONS: SARS-CoV-2 RNAemia and viral RNA load in plasma are associated with critical illness in COVID-19. Viral RNA load in plasma correlates with key signatures of dysregulated host responses, suggesting a major role of uncontrolled viral replication in the pathogenesis of this disease.

Community-Acquired Pneumonia Patients at Risk for Early and Long-term Cardiovascular Events Are Identified by Cardiac Biomarkers.

BACKGROUND: Community-acquired pneumonia (CAP) increases the risk of cardiovascular complications during and following the episode. The goal of this study was to determine the usefulness of cardiovascular and inflammatory biomarkers for assessing the risk of early (within 30 days) or long-term (1-year follow-up) cardiovascular events. METHODS: A total of 730 hospitalized patients with CAP were prospectively followed up during 1 year. Cardiovascular (proadrenomedullin [proADM], pro-B-type natriuretic peptide (proBNP), proendothelin-1, and troponin T) and inflammatory (interleukin 6 [IL-6], C-reactive protein, and procalcitonin) biomarkers were measured on day 1, at day 4/5, and at day 30. RESULTS: Ninety-two patients developed an early event, and 67 developed a long-term event. Significantly higher initial levels of proADM, proendothelin-1, troponin, proBNP, and IL-6 were recorded in patients who developed cardiovascular events. Despite a decrease at day 4/5, levels remained steady until day 30 in those who developed late events. Biomarkers (days 1 and 30) independently predicted cardiovascular events adjusted for age, previous cardiac disease, Pao2/Fio2 < 250 mm Hg, and sepsis: ORs (95% CIs), proendothelin-1, 2.25 (1.34-3.79); proADM, 2.53 (1.53-4.20); proBNP, 2.67 (1.59-4.49); and troponin T, 2.70 (1.62-4.49) for early events. For late events, the ORs (95% CIs) were: proendothelin-1, 3.13 (1.41-7.80); proADM, 2.29 (1.01-5.19); and proBNP, 2.34 (1.01-5.56). Addition of IL-6 levels at day 30 to proendothelin-1 or proADM increased the ORs to 3.53 and 2.80, respectively. CONCLUSIONS: Cardiac biomarkers are useful for identifying patients with CAP at high risk for early and long-term cardiovascular events. They may aid personalized treatment optimization and for designing future interventional studies to reduce cardiovascular risk.