Association Between Blood Eosinophils and Mortality in Critically Ill Patients with Acute Exacerbation of Chronic Obstructive Pulmonary Disease: A Retrospective Cohort Study

Eosinophils and chronic obstructive pulmonary diseases (COPD) in hospitalized COVID-19 patients

BACKGROUND

The emergence of coronavirus disease 2019 (COVID-19) as a global health emergency necessitates continued investigation of the disease progression. This study investigated the relationship between eosinophilia and the severity of COVID-19 in chronic obstructive pulmonary disease (COPD) patients.

METHODS

This cross-sectional study was conducted on 73 COPD patients infected by COVID-19 in Afzalipour Hospital, Iran. Peripheral blood samples were collected for hematological parameter testing, including eosinophil percentage, using Giemsa staining. Eosinophilia was defined as≥ 2% and non-eosinophilia as< 2%. The severity of pulmonary involvement was determined based on chest CT severity score (CT-SS) (based on the degree of involvement of the lung lobes, 0%: 0 points, 1-25%: 1 point, 26-50%: 2 points, 51-75%: 3 points, and 76-100%: 4 points). The CT-SS was the sum of the scores of the five lobes (range 0-20).

RESULTS

The average age of patients was 67.90±13.71 years, and most were male (54.8%). Non-eosinophilic COPD patients were associated with more severe COVID-19 (P= 0.01) and lower oxygen saturation (P= 0.001). In addition, the study revealed a significant difference in the chest CT severity score (CT-SS) between non-eosinophilic (9.76±0.7) and eosinophilic COPD patients (6.26±0.63) (P< 0.001). Although non-eosinophilic COPD patients had a higher mortality rate, this difference was not statistically significant (P= 0.16).

CONCLUSIONS

Our study demonstrated that reduced peripheral blood eosinophil levels in COPD patients with COVID-19 correlate with unfavorable outcomes. Understanding this association can help us identify high-risk COPD patients and take appropriate management strategies to improve their prognosis.

Analysis of sputum microbial flora in chronic obstructive pulmonary disease patients with different phenotypes during acute exacerbations

BACKGROUND

Increasing studies have shown that the imbalance of the respiratory microbial flora is related to the occurrence of COPD, the severity and frequency of exacerbations and mortality.However, it remains unclear how the sputum microbial flora differs during exacerbations in COPD patients manifesting emphysema phenotype, chronic bronchitis with emphysema phenotype and asthma-COPD overlap phenotype.

METHODS

Sputum samples were obtained from 29 COPD patients experiencing acute exacerbations who had not received antibiotics or systemic corticosteroids within the past four weeks.Patients were divided into three groups;emphysema phenotype(E);chronic bronchitis with emphysema phenotype(B+E) and asthma-COPD overlap phenotype(ACO).We utilized metagenomic Next Generation Sequencing (mNGS) technology to analyze the sputum microbial flora in COPD patients with different phenotypes during exacerbations.

RESULTS

There was no significant difference in alpha diversity and beta diversity among three groups.The microbial flora composition was similar in all three groups during exacerbations except for a significant increase in Streptococcus mitis in ACO.Through network analysis,we found Candidatus Saccharibacteria oral taxon TM7x and Fusobacterium necrophorum were the core nodes of the co-occurrence network in ACO and E respectively.They were positively correlated with some species and play a synergistic role.In B+E,Haemophilus pittmaniae and Klebsiella pneumoniae had a synergistic effect.Besides,some species among the three groups play a synergistic or antagonistic role.Through Spearman analysis,we found the relative abundance of Streptococcus mitis was negatively correlated with the number of hospitalizations in the past year(r = -0.410,P = 0.027).We also observed that the relative abundance of Prevotella and Prevotella melaninogenica was negatively correlated with age(r = -0.534,P = 0.003;r = -0.567,P = 0.001),while the relative abundance of Streptococcus oralis and Actinomyces odontolyticus was positively correlated with age(r = 0.570,P = 0.001;r = 0.480,P = 0.008).In addition,the relative abundance of Prevotella melaninogenica was negatively correlated with peripheral blood neutrophil ratio and neutrophil to lymphocyte ratio(r = -0.479,P = 0.009;r = -0.555,P = 0.002),while the relative abundance of Streptococcus sanguinis was positively correlated with peripheral blood neutrophil ratio and neutrophil to lymphocyte ratio (r = 0.450,P = 0.014;r = 0.501,P = 0.006).There was also a significant positive correlation between Oribacterium and blood eosinophil counts(r = 0.491,P = 0.007).

CONCLUSION

Overall,we analyzed the sputum microbiota of COPD patients with different phenotypes and its relationship with clinical indicators, and explored the relationships between microbiota and inflammation in COPD.We hope to alter the prognosis of patients by inhibiting specific bacterial taxa related to inflammation and using guide individualized treatment in the future research.

Outcome Prediction in Critically-Ill Patients with Venous Thromboembolism and/or Cancer Using Machine Learning Algorithms: External Validation and Comparison with Scoring Systems

Intensive care unit (ICU) patients with venous thromboembolism (VTE) and/or cancer suffer from high mortality rates. Mortality prediction in the ICU has been a major medical challenge for which several scoring systems exist but lack in specificity. This study focuses on two target groups, namely patients with thrombosis or cancer. The main goal is to develop and validate interpretable machine learning (ML) models to predict early and late mortality, while exploiting all available data stored in the medical record. To this end, retrospective data from two freely accessible databases, MIMIC-III and eICU, were used. Well-established ML algorithms were implemented utilizing automated and purposely built ML frameworks for addressing class imbalance. Prediction of early mortality showed excellent performance in both disease categories, in terms of the area under the receiver operating characteristic curve (AUC–ROC): VTE-MIMIC-III 0.93, eICU 0.87, cancer-MIMIC-III 0.94. On the other hand, late mortality prediction showed lower performance, i.e., AUC–ROC: VTE 0.82, cancer 0.74–0.88. The predictive model of early mortality developed from 1651 VTE patients (MIMIC-III) ended up with a signature of 35 features and was externally validated in 2659 patients from the eICU dataset. Our model outperformed traditional scoring systems in predicting early as well as late mortality. Novel biomarkers, such as red cell distribution width, were identified.

Usefulness of Glucose to Lymphocyte Ratio to Predict in-Hospital Mortality in Patients with AECOPD Admitted to the Intensive Care Unit

The purpose of this study was to investigate the relationship between glucose to lymphocyte ratio (GLR) and the outcome of acute exacerbation chronic obstructive pulmonary disease (AECOPD) patients admitted to the intensive care unit (ICU). This study included 3573 patients from the eICU Collaborative Research Database (eICU-CRD) and 926 AECOPD patients admitted to ICU from the Medical Information Mart for Intensive Care-IV (MIMIC-IV) database. The optimal cutoff value for GLR was 5.6. Kaplan-Meier analysis demonstrated that patients in lower GLR (< 5.6) group showed a better overall survival than patients in higher GLR (≥ 5.6) group in all sets. Multivariate Cox regression analysis demonstrated that age, Sequential Organ Failure Assessment (SOFA) score, SpO2, albumin and GLR are independent predictors of poor overall survival in the training cohort and were incorporated into the nomogram for in-hospital mortality as independent factors. The nomogram exhibited excellent discrimination with C-indexes in training cohort, internal validation and external validation cohort were (0.801, 95%CI: 0.769-0.863), (0.805, 95%CI: 0.759-0.851) and (0.811, 95%CI: 0.772-0.850), respectively. The calibration plot indicated an adequate fit of the nomogram for predicting the risk of in-hospital mortality in all sets. Moreover, the ROC analyses demonstrated that the discrimination abilities of GLR were better than other blood-based inflammatory biomarkers. As an easily available biomarker, GLR can independently predict the in-hospital mortality in AECOPD patients admitted to ICU. The nomogram combining GLR with other significant indicators exhibited excellence predictive performance for in-hospital mortality.

Stability of blood eosinophils in acute exacerbation of chronic obstructive pulmonary disease and its relationship to clinical outcomes: a prospective cohort study

BACKGROUND

The clinical value of blood eosinophils and their stability in chronic obstructive pulmonary disease (COPD) remains controversial. There are limited studies on association between the stability of blood eosinophils in acute exacerbation of COPD (AECOPD) and clinical outcomes. This study aimed to evaluate the stability of blood eosinophils in hospitalized AECOPD and its relationship to clinical outcomes.

METHODS

This prospective observational study recruited patients hospitalized with AECOPD from November 2016 to July 2020. The eligible patients were divided into four groups according to their blood eosinophil counts at admission and discharge: persistently < 300 cells/μl (LL), < 300 cells/μl at admission but ≥ 300 cells/µl at discharge (LH), ≥ 300 cells/μl at admission but < 300 cells/µl at discharge (HL), and persistently ≥ 300 cells/μl (HH). Cox hazard analyses were used to study the association between eosinophil changes and exacerbations or mortality.

RESULTS

In 530 patients included, 90 (17.0%) had a high blood eosinophil count (BEC) ≥ 300 cells/µl at admission but 32 (35.6%) of them showed a decreased BEC at discharge. The proportions and distribution for group LL, LH, HL, and HH were 381 (71.9%), 59 (11.1%), 32 (6.0%), and 58 (10.9%), respectively. During hospitalization, the LH group had a higher C-reactive protein level, higher rate of intensive care unit (ICU) admission, and higher total cost. The length of hospital stay of the LH group was longer compared with group LL, HL, or HH (P = 0.002, 0.017, and 0.001, respectively). During a follow-up of 12 months, the HH group was associated with a higher risk of moderate-to-severe exacerbations compared to the LL group (hazard ratio 2.00, 95% confidence interval 1.30-3.08, P = 0.002). Eosinophil changes had no significant association with mortality at 12 months. Sensitivity analyses in patients without asthma and without use of systemic corticosteroids prior to admission did not alter the results.

CONCLUSIONS

More attention should be paid to the LH group when evaluating the short-term prognosis of AECOPD. A persistently high BEC was a risk factor for long-term exacerbations. Eosinophil changes during hospitalization could help to predict outcomes.

Inhaled corticosteroid dose is associated with Pseudomonas aeruginosa infection in severe COPD

INTRODUCTION

Patients with chronic obstructive pulmonary disease (COPD) with frequent exacerbations (ExCOPD) are commonly treated with inhaled corticosteroids (ICS) and are at risk of infections caused by potential pathogenic bacteria (PPB) including Pseudomonas aeruginosa (PsA).

OBJECTIVES

To investigate the association between the use of ICS and PsA infection among ExCOPD.

METHODS

Case-control study with longitudinal follow-up that recruited ExCOPD after a hospitalisation due to exacerbation between 2012 and 2020. Patients with isolation of PsA (COPD-PsA) in sputum either during admission or follow-up were compared with those with other or no PPB. Clinical, functional characteristics, DDD, use of ICS and survival were evaluated. Cox regression analysis was performed to evaluate the risk factors associated to PsA infection and mortality.

RESULTS

358 patients (78% male, mean age 73±9 years) were enrolled and followed up for a median of 4 years (IQR=3-8). 173 patients (48.3%) had at least a positive culture for PsA. COPD-PsA had more frequent exacerbations, more severe airflow limitation and higher mortality (69.4% vs 46.5%, p<0.001). There were no differences in the use of ICS between groups but the dose of ICS was significantly higher among COPD-PsA (median of 500 µg fluticasone propionate equivalents (IQR=250-1000) vs 400 µg (IQR=200-1000), p=0.007). Blood eosinophil count (BEC) was not different between ICS users and non-users. In multivariate analysis, the dose of ICS was an independent risk factor for PsA infection and mortality but not ICS use.

CONCLUSIONS

ICS dose, but not its use, could be a risk factor for PsA infection in patients with severe COPD regardless of BEC.

Characterization of COPD Admissions During the First COVID-19 Outbreak

Purpose

Exacerbations of COPD (ECOPD) are a frequent cause of hospitalization that seemed to ameliorate during the COVID outbreak. We aimed to evaluate the clinical characteristics of COPD-related hospital admissions and mortality in relation to the presence of COVID-19.

Patients and Methods

We conducted a case-control study of patients admitted in four teaching hospitals throughout Spain between March 15 and April 30, 2020. Hospital admissions of respiratory cause with and without PCR-proven SARS-CoV-2 infection in patients with COPD were evaluated. Baseline and episode-related clinical characteristics were analyzed. Logistic regression analysis was performed to evaluate the risk for mortality.

Results

During the study period, 2101 patients were admitted for respiratory worsening, 1200 (57.1%) with COVID-19. A total of 228 (10.8%) were admitted due to COPD worsening, of whom 52 (22.8%) tested positive for COVID-19. COPD patients with COVID-19, when compared to those without COVID-19, were more frequently males with better lung function (FEV₁ postbronchodilator 71% vs 46% respectively, p<0.001) and had higher mortality (44.9% vs 13.6% respectively, p<0.001) despite similar age, comorbidities, total days of hospitalization and admission to intensive care unit. COVID-19 and eosinopenia were the strongest risk factors for mortality in the multivariate analysis in the overall COPD population. Inhaled corticosteroid use was not associated to mortality.

Conclusion

Hospitalizations for ECOPD without COVID-19 were more frequent than COPD with COVID-19 during the first outbreak, but the latter were associated with higher mortality and low eosinophil counts that warrant further analysis.