Peripheral Blood Eosinophil as a Biomarker in Outcomes of Acute Exacerbation of Chronic Obstructive Pulmonary Disease

Gaining insights into chronic obstructive pulmonary disease exacerbation through emerging biomarkers and the chronic obstructive pulmonary disease assessment test score

Chronic obstructive pulmonary disease (COPD), a leading cause of mortality and morbidity, presents significant challenges, particularly with exacerbations, which drastically impact patients' health and healthcare costs. The Global Initiative for Chronic Obstructive Lung Disease guidelines recommend comprehensive assessments beyond spirometry, with the COPD assessment test (CAT) emerging as a pivotal tool. Despite its utility, the relationship between CAT scores and specific biomarkers during exacerbations remains unclear. Hence, this study aims to assess the correlation between the CAT score and specific circulating biomarkers. A cross-sectional study from August 2023 to January 2024 included 59 COPD patients with exacerbations who underwent pulmonary function tests and completed the CAT score assessment. The CAT score cut-off point was set at 20, where a CAT score <20 indicated a low impact on health status and a CAT score ≥20 indicated a high impact on health status. On the same day, measurements of neutrophils, leukocytes, eosinophils, C-reactive protein, and procalcitonin were conducted. Patients with CAT scores ≥20 had significantly higher levels of neutrophils (p=0.001), leukocytes (p=0.006), procalcitonin (p=0.010), and forced expiratory volume in the first second/forced vital capacity (p=0.002), but lower eosinophil levels (p=0.025). A positive correlation existed between total CAT score and neutrophils (p=0.001), leukocytes (p=0.000), and procalcitonin (p=0.010), while eosinophil levels showed a negative correlation (p=0.025). The spirometry parameters showed no correlation with the total CAT score. This study highlights the link between CAT and key inflammatory biomarkers, supporting the use of blood biomarkers to identify COPD patients at risk of exacerbations.

A Low Eosinophil to Platelet Ratio as a Worse Prognostic Index for Emergency Department Attendance in Acute Exacerbation of COPD

Purpose

Identifying prognosis for patients with acute exacerbation of chronic obstructive pulmonary disease (AECOPD) is challenging. Eosinophils and platelet are involved in the development of COPD, which may predict adverse events. The objective of this study was to determine the effect of the eosinophil to platelet ratio (EPR) in predicting adverse events in patients with AECOPD who visited the emergency department.

Patients and Methods

The records of patients with AECOPD treated at Dalian Municipal Friendship Hospital from January 2018 to December 2020 were retrospectively reviewed. The relationship between the clinical characteristics and EPR, as cut-off value of 0.755, was evaluated.

Results

A total of 508 patients with an AECOPD (316 male, 192 female) were included. An optimal AUC cutoff of 0.755 for the EPR segregated the patients into 2 groups with significantly different mortality (25.3% vs 5.5%, P < 0.001). The same mortality risk with lower EPR was observed among the patients with emergency room attendance (35.6% vs 11.1%, P < 0.001). A model including EPR <0.755, exacerbation history, PaO2 <60mmHg, PaCO2 >50 mm Hg, hypoalbuminemia and age ≥80 was developed to predict death risk and showed good performance.

Conclusion

During severe COPD exacerbation, an EPR < 0.755 preceding therapy can predict worse outcomes in patients with an AECOPD.

Admission blood eosinophil count, inpatient death and death at 1 year in exacerbating patients with COPD

BACKGROUND

Blood eosinophil counts have been studied in patients with stable chronic obstructive pulmonary disease (COPD) and are a useful biomarker to guide inhaled corticosteroid use. Less is known about eosinophil counts during severe exacerbation.

METHODS

In this retrospective study, 2645 patients admitted consecutively with COPD exacerbation across six UK hospitals were included in the study, and the clinical diagnosis was confirmed by a respiratory specialist. The relationship between admission eosinophil count, inpatient death and 1-year death was assessed. In a backward elimination, Poisson regression analysis using the log-link function with robust estimates, patients' markers of acute illness and stable-state characteristics were assessed in terms of their association with eosinopenia.

RESULTS

1369 of 2645 (52%) patients had eosinopenia at admission. Those with eosinopenia had a 2.5-fold increased risk of inpatient death compared with those without eosinopenia (12.1% vs 4.9%, RR=2.50, 95% CI 1.88 to 3.31, p<0.001). The same mortality risk with eosinopenia was seen among the subgroup with pneumonic exacerbation (n=788, 21.3% vs 8.5%, RR=2.5, 95% CI 1.67 to 2.24, p<0.001). In a regression analysis, eosinopenia was significantly associated with: older age and male sex; a higher pulse rate, temperature, neutrophil count, urea and C reactive protein level; a higher proportion of patients with chest X-ray consolidation and a reduced Glasgow Coma Score; and lower systolic and diastolic blood pressure measurements and lower oxygen saturation, albumin, platelet and previous admission counts.

DISCUSSION

During severe COPD exacerbation, eosinopenia is common and associated with inpatient death and several markers of acute illness. Clinicians should be cautious about using eosinophil results obtained during severe exacerbation to guide treatment decisions regarding inhaled corticosteroid use.

Associations of Smoking, Cytomegalovirus Serostatus, and Natural Killer Cell Phenotypes in Smokers With and At Risk for COPD

Introduction

Chronic obstructive disease (COPD) risk factors, smoking, and chronic infection (cytomegalovirus [CMV]) may mold natural killer (NK) cell populations. What is not known is the magnitude of the effect CMV seropositivity imparts on populations of smokers with and at risk for COPD. We investigate the independent influence of CMV seropositivity on NK cell populations and differential effects when stratifying by COPD and degree of smoking history.

Methods

Descriptive statistics determine the relationship between cytotoxic NK cell populations and demographic and clinical variables. Multivariable linear regression and predictive modeling were performed to determine associations between positive CMV serology and proportions of CD57+ and natural killer group 2C (NKG2C)+ NK cells. We dichotomized our analysis by those with a heavy smoking history and COPD and described the effect size of CMV seropositivity on NK cell populations.

Results

When controlled for age, race, sex, pack-years smoked, body mass index, and lung function, CMV+ serostatus was independently associated with a higher proportion of CD57+, NKG2C+, and NKG2C+CD57+ NK cells. CMV+ serostatus was the sole predictor of larger NKG2C+ and CD57+NKG2C+ populations. Associations are more pronounced in those with COPD and heavy smokers.

Conclusions

Among Veterans who are current and former smokers, CMV+ serostatus was independently associated with larger CD57+ and NKG2C+ populations, with a larger effect in heavy smokers and those with COPD, and was the sole predictor for increased expression of NKG2C+ and CD57+NKG2C+ populations. These findings may be broadened to include the assessment of longitudinal NK cell population change, accrued inflammatory potential, and further identification of pro-inflammatory NK cell population clusters.

Excess of blood eosinophils prior to therapy correlates with worse prognosis in mesothelioma

Background

Only a fraction of patients with malignant pleural mesothelioma (MPM) will respond to chemo- or immunotherapy. For the majority, the condition will irremediably relapse after 13 to 18 months. In this study, we hypothesized that patients' outcome could be correlated to their immune cell profile. Focus was given to peripheral blood eosinophils that, paradoxically, can both promote or inhibit tumor growth depending on the cancer type.

Methods

The characteristics of 242 patients with histologically proven MPM were retrospectively collected in three centers. Characteristics included overall survival (OS), progression-free survival (PFS), overall response rate (ORR) and disease control rate (DCR). The mean absolute eosinophil counts (AEC) were determined by averaging AEC data sets of the last month preceding the administration of chemo- or immunotherapy.

Results

An optimal cutoff of 220 eosinophils/µL of blood segregated the cohort into two groups with significantly different median OS after chemotherapy (14 and 29 months above and below the threshold, p = 0.0001). The corresponding two-year OS rates were 28% and 55% in the AEC ≥ 220/µL and AEC < 220/µL groups, respectively. Based on shorter median PFS (8 vs 17 months, p < 0.0001) and reduced DCR (55.9% vs 35.2% at 6 months), the response to standard chemotherapy was significantly affected in the AEC ≥ 220/µL subset. Similar conclusions were also drawn from data sets of patients receiving immune checkpoint-based immunotherapy.

Conclusion

In conclusion, baseline AEC ≥ 220/µL preceding therapy is associated with worse outcome and quicker relapse in MPM.

Blood and sputum eosinophilia in COPD exacerbation

Background

Exacerbations in chronic obstructive pulmonary disease (COPD) are major contributors to worsening lung function, impaired quality of life, emergency healthcare use, and COPD-related mortality. COPD exacerbations are heterogeneous in terms of airway inflammation and etiology.

Objectives

To assess the relation between blood and sputum eosinophils and COPD exacerbation.

Subjects and methods

Prospective cohort study, conducted on 100 COPD patients presented in outpatient clinic. All patients were subjected to medical history including: occupational history, smoking history, comorbidity, number of exacerbations in last year and their degree, history of admission in the last year and treatment taken for COPD. Modified Medical Research Council scale of dyspnea, peak expiratory flow rate, oxygen saturation using pulse oximetry. Complete blood count with differential eosinophilic count. Sputum sample differential cell count was done.

Results

The eosinophil level in blood before and after treatment showed a significant positive correlation with the number of hospital admission in the last year (r = 0.29; P = 0.003 and r = 0.3; P = 0.002, respectively). Regarding the eosinophil level either in blood or in sputum, it showed significant statistical elevation in patients not using steroid treatment in comparison to patients who used systemic or inhaled steroid treatments (P < 0.001 and 0.004, respectively).

Conclusion

Blood eosinophil count can be used as a severity marker of COPD exacerbations. The eosinophil levels, either in blood or sputum, were significantly correlated with the degree of exacerbation. Sputum eosinophilia can also predict the risk of hospitalization. In addition, blood eosinophil count can direct the use of oral corticosteroids in exacerbation.

Using inflammatory index to distinguish asthma, asthma-COPD overlap and COPD: A retrospective observational study

BACKGROUND

Although asthma and chronic obstructive pulmonary disease (COPD) are two well-defined and distinct diseases, some patients present combined clinical features of both asthma and COPD, particularly in smokers and the elderly, a condition termed as asthma-COPD overlap (ACO). However, the definition of ACO is yet to be established and clinical guidelines to identify and manage ACO remain controversial. Therefore, in this study, inflammatory biomarkers were established to distinguish asthma, ACO, and COPD, and their relationship with the severity of patients' symptoms and pulmonary function were explored.

MATERIALS AND METHODS

A total of 178 patients, diagnosed with asthma (n = 38), ACO (n = 44), and COPD (n = 96) between January 2021 to June 2022, were enrolled in this study. The patients' pulmonary function was examined and routine blood samples were taken for the analysis of inflammatory indexes. Logistic regression analysis was used to establish inflammatory biomarkers for distinguishing asthma, ACO, and COPD; linear regression analysis was used to analyze the relationship between inflammatory indexes and symptom severity and pulmonary function.

RESULT

The results showed that, compared with ACO, the higher the indexes of platelet, neutrophil-lymphocyte ratio (NLR) and eosinophil-basophil ratio (EBR), the more likely the possibility of asthma and COPD in patients, while the higher the eosinophils, the less likely the possibility of asthma and COPD. Hemoglobin and lymphocyte-monocyte ratio (LMR) were negatively correlated with the severity of patients' symptoms, while platelet-lymphocyte ratio (PLR) was negatively correlated with forced expiratory volume in the 1 s/forced vital capacity (FEV1/FVC) and FEV1 percent predicted (% pred), and EBR was positively correlated with FEV1% pred.

CONCLUSION

Inflammatory indexes are biomarkers for distinguishing asthma, ACO, and COPD, which are of clinical significance in therapeutic strategies and prognosis evaluation.

Clinical features and three-year prognosis of AECOPD patients with different levels of blood eosinophils

BACKGROUND

Eosinophils are thought to be associated with the frequency and severity of acute exacerbations of chronic obstructive pulmonary disease (AECOPD); however, the role of eosinophilic inflammation in AECOPD is still incompletely understood.

OBJECTIVES

To investigate the relationship between different levels of blood eosinophils and clinical features, including comorbidities, therapy, and prognosis, and to further explore the optimal eosinophilic cutoff.

METHODS

We retrospectively collected and analyzed medical data, laboratory findings, chest CT images, treatment, and three-year follow-up data from 984 AECOPD patients with different blood eosinophil (EOS) levels: EOS%<2%, ≥2%; EOS%<3%, ≥3%; eosinophil counts<100 cells/L, ≥100 cells/L.

RESULTS

The prevalence of eosinophilia was 36.48% of EOS≥2% (359 cases), 22.87% of EOS≥3% (225 cases), and 48.48% with eosinophil counts≥100 cells/µl (477 cases). EOS was associated with comorbidities, including pulmonary heart disease, arrhythmia (atrial fibrillation), laboratory testing and clinical treatment, including respiratory failure, airway limitation, infectious inflammation, rate of antibiotic use, systemic glucocorticoids, and three mortality rates. The ROC curve showed that the indicators of AUC≥0.5 included chest CT imaging (emphysema 1.8% or ≥100/µl, bronchitis, 1.7% or ≥100/µl), osteoporosis (2.4% or ≥140/µl), mental illness 6.1% (or ≥400/µl), dust exposure (2.2% or ≥240/µl) and ex-smoker (1.3% or ≥100/µl).

CONCLUSIONS

The relatively higher EOS group (≥2% or ≥100/µl) was associated with fewer complications, mild airflow limitation, a tendency of noninfectious inflammation, and lower 3-year mortality. Eosinophils can not only guide clinical treatment but also be an indicator of predicting clinical outcome and prognosis in AECOPD patients.

Novel Applications of Biomarkers in Chronic Obstructive Pulmonary Disease

Chronic obstructive pulmonary disease (COPD) is an important health problem and an increasing cause of morbidity and mortality worldwide. Currently, COPD is considered a multisystem disease. Although it primarily affects the lungs, structural and functional changes occur in other organs due to systemic inflammation. It is stated that in patients with COPD, airway and systemic inflammatory markers are increased and that these markers are high are associated with a faster decline in lung functions. In recent years, numerous articles have been published on the discovery and evaluation of biomarkers in COPD. Many markers have also been studied to accurately assess COPD exacerbations and provide effective treatment. However, based on the evidence from published studies, a single molecule has not been adequately validated for broad clinical use.

Practical parameters that can be used for nutritional assessment in patients hospitalized in the intensive care unit with the diagnosis of chronic obstructive pulmonary disease: Prognostic nutritional index, neutrophil-to-lymphocyte, platelet-to-lymphocyte, and lymphocyte-to-monocyte ratio

Malnutrition is an important condition in patients diagnosed with chronic obstructive pulmonary disease (COPD). There is a need for practical and objective nutritional assessment methods in patients hospitalized in the intensive care unit with the diagnosis of COPD. In this study, it was aimed to determine the parameters that can practically evaluate the nutritional status of these patients. It was aimed to determine the relationship between prognostic nutritional index (PNI), and nutritional risk screening (NRS)-2002, nutrition risk in the critical ill (Nutric) Score and to determine a cut-off value for PNI, neutrophil-to-lymphocyte (NLR), platelet-to-lymphocyte ratio (PLR), lymphocyte-to-monocyte ratio (LMR), and other complete blood count parameters.Hemogram values, albumin values, NLR, PLR, LMR, NRS-2002, PNI and modified Nutric Score calculations of the patients hospitalized in the intensive care unit due to COPD were recorded. The relationship between PNI and NRS-2002 and modified Nutric Score, as well as the relationship between NLR, PLR, LMR, hemogram parameters and PNI were analyzed using statistical methods.The PNI cut-off value for nutritional assessment in patients hospitalized in the intensive care unit due to COPD was determined as 38.5 (area under curve = 0.891, sensitivity 80.8%, specificity 88.1%, positive predictive value 92.9%, negative predictive value 88%). High-risk group according to PNI compared to low-risk group, lymphocyte count (P < .001), basophil count (P = .004), red blood cell (P < .001), hemoglobin (P < .001), hematocrit (P < .001), and LMR (P = .001) were statistically significantly lower, while NLR (P < .001) and PLR (P = .001) were statistically significantly higher. Cut-off values for lymphocyte count, basophil count, NLR, PLR, and LMR were found to be 1.18, 0.035, 7.97, 291.10, and 2.606, respectively.Nutritional risk assessment can be made in a practical way by using PNI in patients hospitalized in intensive care unit due to COPD. For this, the PNI cut-off value was determined as 38.5 in our study. In addition, NLR, PLR, LMR, basophil and lymphocyte values, which can be calculated using complete blood count parameters, may also be useful in the evaluation of nutritional status in these patients. In our study, the cut-off values determined for NLR, PLR, LMR, basophil and lymphocyte were 7.97, 291.10 and 2.606, 0.035 and 1.18, respectively. We think that the results we have obtained can provide preliminary information for future research.

Blood Eosinophils in Chinese COPD Participants and Response to Treatment with Combination Low-Dose Theophylline and Prednisone: A Post-Hoc Analysis of the TASCS Trial

Background and Objectives

The burden of chronic obstructive pulmonary disease (COPD) disproportionately affects patients in low to middle-income countries. Although the Theophylline and Steroids in COPD Study (TASCS) showed no clinical benefit from administering low-dose theophylline and prednisone in COPD patients compared to placebo, it was hypothesized that those with elevated blood eosinophil counts would receive clinical benefit from the intervention.

Methods

This was a post-hoc analysis of the TASCS dataset – a double-blinded, placebo-controlled trial conducted in patients with moderate–severe COPD in China. Participants were allocated 1:1:1 to low-dose oral theophylline (100mg bd) and prednisone (5mg qd; PrT), theophylline (100mg bd) and prednisone-matched placebo (TP), or double-matched placebo (DP) groups and followed-up for 48 weeks. A baseline count of ≥300 eosinophils/µL blood was categorized as elevated/eosinophilic, and the primary outcome was the annualized moderate-severe exacerbation rate.

Results

Of 1487 participants eligible for analysis, 325 (22%) were eosinophilic. These participants were predominantly male (82%), had a mean (SD) age of 64 (±8) years and a predicted forced expiratory volume in 1s (FEV₁) of 43% (±16). The annualized moderate–severe exacerbation rate was significantly higher in the PrT group compared to the pooled results of the TP and DP groups (incidence rate ratio = 1.6; ([95% CI 1.06–1.76]) p = 0.016). Changes in spirometry values and reported disease impact scores (St. George’s Respiratory Questionnaire and COPD Assessment Test) at week 48 were not significantly different between groups.

Conclusion

Combination low-dose theophylline and prednisone was associated with a significant increase in the annual moderate-severe exacerbation rate in participants with a blood eosinophil count ≥300 cells/µL compared to placebo.

Predictors of Influenza PCR Positivity in Acute Exacerbations of Chronic Obstructive Pulmonary Disease

Purpose

Influenza infection is an important cause of acute exacerbation of chronic obstructive pulmonary disease (AECOPD). Clinical features predicting influenza PCR positivity are unknown. We aim to identify predictors of influenza PCR positivity in AECOPD.

Patients and Methods

A retrospective study of AECOPD cases admitted between 1st January 2016 to 30 June 2017 with combined nasal/throat swabs sent for influenza PCR (Xpert Xpress Flu/RSV) within 24 hours of admission was performed. Clinical parameters and investigations within 24 hours of admission were retrieved from electronic medical records.

Results

Influenza PCR were sent for 925 AECOPD cases (mean age 75 years, 87.9% male). There were 90 PCR positive cases (68 Influenza A, 22 Influenza B). Influenza PCR positive cases had higher temperatures, higher heart rates, lower white cell and lower eosinophil counts. Age, gender, COPD severity, comorbidities and smoking status were similar in both groups. There were no differences in blood pressure, oxygen status, neutrophil or lymphocyte counts, C reactive protein, procalcitonin or chest X-ray consolidation between groups. Higher temperature, higher heart rate, white cell count in the lowest quartile (Q1 < 8.1 x10⁹/L) and non-eosinophilic exacerbations predicted influenza PCR positivity on univariate logistic regression and these factors remained significant after multivariate adjustment (temperature adjusted odds ratio [adj OR] 1.324 [1.009–1.737], p = 0.043; heart rate adj OR 1.017 [1.004–1.030], p = 0.011; white cell count Q1 adj OR 3.330 [1.690–6.562], p = 0.001; eosinophilic exacerbations adj OR 0.390 [0.202–0.756], p = 0.005).

Conclusion

Higher temperature, higher heart rate, low white cell count (especially when < 8.1 x10⁹/L) and non-eosinophilic exacerbations are independent predictors of influenza PCR positivity in AECOPD cases.

Characteristics of length of stay and cardiovascular pharmacotherapy advice among chronic obstructive pulmonary disease patients

Chronic obstructive pulmonary disease (COPD) increases the global disease burden due to its diverse adverse health effects on the respiratory and cardiovascular systems. This study aimed to elucidate the potential indicators of length of stay (LOS) and pharmacotherapy advice among COPD patients. Thereafter, hospitalized COPD patients with clinical records and respiratory and cardiovascular pharmacotherapy advice were retrospectively collected from a tertiary hospital between April 2017 and September 2020, and the determinants of LOS and cardiovascular pharmacotherapy advice were explored using regression analyses. Overall, 475 patients with COPD were recruited and stratified according to exacerbation and presence of Cor pulmonale (CP). The extended LOS, increased B-type natriuretic peptides (BNP), and a higher percentage of cardiovascular pharmacotherapy advice were observed in COPD with CP regardless of exacerbation, although the percentage of respiratory prescriptions was comparable. The presence of CP indicated a longer LOS (B = 1.850, p < 0.001) for COPD regardless of exacerbation. Meanwhile, elevated BNP levels indicated cardiovascular pharmacotherapy advise for both COPD in exacerbation (OR = 1.003, p = 0.012) and absence of exacerbation (OR = 1.006, p = 0.015). Moreover, advice for trimetazidine use for COPD in exacerbation (OR = 1.005, p = 0.002) has been suggested. Therefore, CP appears to be an important comorbidity resulting in extended LOS for COPD, which is likely to be advised with cardiovascular pharmacotherapy, which might be guided through BNP monitoring.

Eosinophilic phenotype was associated with better early clinical remission in elderly patients but not middle-aged patients with acute exacerbations of COPD

BACKGROUND

There is limited evidence of the relationship between peripheral blood eosinophils and clinical remission of acute exacerbations of chronic obstructive pulmonary disease (AECOPD) at different ages, especially in elderly patients, which was the objective of the present study.

METHODS

This retrospective study stratified patients by age (elderly patients >65 years old or middle-aged patients between 45 and 65 years old) and analysed the relationship between blood eosinophils (≥2% or <2%) and AECOPD clinical remission at observing time points of 7, 14, 21 and 28 days of hospitalisation. Student's t tests, Mann-Whitney U tests, Chi-squared or Fisher's exact tests were conditionally used to compare difference between groups. The unadjusted or adjusted Cox proportional hazards model was used to analyse the association between blood eosinophilic levels and cumulative clinical remission.

RESULTS

Of 703 AECOPD cases analysed, 616 were elderly people (>65 years), 312 of whom had eosinophilic exacerbations. There were statistically significant differences in leucocytes, eosinophils, neutrophils, lymphocytes, monocytes, high-sensitivity C-reactive protein levels (hs-CRP), and hospital costs between groups (P < .05, respectively). According to the chi-square analysis, eosinophilic exacerbation had a higher clinical remission rate at 7, 14 and 21 days (all P < .05), but not 28 days (P > .05). Among analysis through adjusted Cox proportional hazards model, eosinophilic exacerbation was significantly associated with a higher cumulative remission rate in elderly patients at 7, 14, 21 days (all P < .05), but not 28 days (P > .05). No significant association was observed in meddle-aged patients at any time points (all P > .05).

CONCLUSION

Eosinophilic exacerbation was associated with better early clinical remission of AECOPD patients during hospitalisation. As stratified by ages, similar results were observed in elderly patients but not middle-aged patients. Blood eosinophils at different ages may be valuable in personalised management for AECOPD.

Blood Eosinophils and Clinical Outcomes in Patients With Acute Exacerbation of Chronic Obstructive Pulmonary Disease: A Propensity Score Matching Analysis of Real-World Data in China

Background and Objective: Elevated eosinophils in chronic obstructive pulmonary disease (COPD) are recognized as a biomarker to guide inhaled corticosteroids use, but the value of blood eosinophils in hospitalized exacerbations of COPD remains controversial. This study aimed to evaluate the accuracy of eosinophils in predicting clinical outcomes in acute exacerbation of COPD (AECOPD).

Methods: We analyzed data from the acute exacerbation of chronic obstructive pulmonary disease inpatient registry (ACURE) study, which is an ongoing nationwide multicenter, observational real-world study in patients admitted for AECOPD. Data collected between January 2018 and December 2019 in 163 centers were first reviewed. The eligible patients were divided into eosinophilic and non-eosinophilic groups, according to blood eosinophil with 2% of the total leukocyte count as the threshold. Propensity score (PS) matching was performed to adjust for confounders.

Results: A total of 1,566 patients (median age: 69 years; 80.3% male) were included and 42.7% had an eosinophilic AECOPD. Eosinophil count <2% was associated with the development of respiratory failure and pneumonia. After PS matching, 650 pairs in overall patients, 468 pairs in patients with smoking history and 177 pairs in patients without smoking were selected, respectively. Only in patients with smoking history, the non-eosinophilic AECOPD was associated with longer median hospital stays (9 vs. 8 days, P = 0.034), higher dosage of corticosteroid use, higher economic burden of hospitalization, and poorer response to corticosteroid therapy compared to the eosinophilic AECOPD. No significant difference was found in patients without smoking. Eosinophil levels had no relationship with the change of COPD Assessment Test scores and readmissions or death after 30 days.

Conclusion: Elevated eosinophils were associated with better short-term outcomes only in patients with a smoking history. Eosinophil levels cannot be confidently used as a predictor alone for estimating prognosis.

Biomarkers as a Prognostic Factor in COPD Exacerbation: A Cohort Study

The acute exacerbations of COPD (AECOPD) are one of the main causes of hospitalization and morbimortality in the adult population. There are not many tools available to predict the clinical course of these patients during exacerbations. Our goal was to estimate the clinical utility of C Reactive Protein (CRP), Mean Platelet Volume (MPV), eosinophil count and neutrophil/lymphocyte ratio (NLR) as in-hospital prognostic factors in patients with AECOPD. A prospective cohort study was conducted in patients who consulted three reference hospitals in the city of Medellín for AECOPD and who required hospitalization between 2017 and 2020. A multivariate analysis was performed to estimate the effect of biomarkers in the two primary outcomes: the composite outcome of in-hospital death and/or admission to the ICU and hospital length-of-stay. A total of 610 patients with a median age of 74 years were included; 15% were admitted to the ICU and 3.9% died in the hospital. In the multivariate analysis adjusted for confounding variables, the only marker significantly associated with the risk of dying or being admitted to the ICU was the NLR > 5 (OR: 3; CI95%: 1.5; 6). Similarly, the NLR > 5 was also associated to a lower probability of being discharged alive from the institution (SHR: 0.73; CI95%: 0.57; 0.94) and, therefore, a longer hospital stay. It was found that a neutrophil/lymphocyte ratio greater than 5 is a strong predictor of mortality or ICU admissions and a longer hospital stay in patients hospitalized with AECOPD.

Blood eosinophils as predictor of outcomes in patients hospitalized for COPD exacerbations: a prospective observational study

PURPOSE

In the present prospective multicentre observational study, we evaluated the potential role of blood eosinophils on the outcomes of patients hospitalized for COPD exacerbations.

MATERIAL AND METHODS

Consecutive patients >40 years with a previous COPD diagnosis were recruited. Blood eosinophils were measured on admission prior to the initiation of treatment and were evaluated in three groups (<50, 50-149 and ≥150 cells/μL). Patients received standard care and were followed up for a year.

RESULTS

A total of 388 patients were included (83.5% male, mean age 72 years). Patients with higher blood eosinophils had less dyspnoea (Borg scale), lower C-reactive protein (CRP) and higher PaO₂/FiO₂ (partial pressure for oxygen/fraction of inhaled oxygen), and were discharged earlier (median 11 vs. 9 vs. 5 days for patients with <50, 50-149 and ≥150 cells/μL, respectively). Patients with <50 cells/μL presented higher 30-day and 1-year mortality, whereas there were no differences in moderate/severe COPD exacerbations between the three groups. In a post hoc analysis, treatment with inhaled corticosteroids as per physicians' decision was associated with better exacerbation prevention during follow-up in patients with ≥150 cells/μL.

CONCLUSIONS

Higher blood eosinophils were associated with better outcomes in hospitalized COPD patients, further supporting their use as a prognostic biomarker.

Epidemiology and issues of NIV-treated AECOPD patients with hypercapnic respiratory failure in Shanghai: A multicentre retrospective survey

OBJECTIVE

To investigate the epidemiology, clinical features, treatment and outcome of Noninvasive ventilation (NIV)-treated acute exacerbation of chronic obstructive pulmonary disease (AECOPD) patients in secondary hospitals of Shanghai.

METHOD

Relying on Shanghai alliances for respiratory diseases, a retrospective observational study was performed in 34 secondary hospitals of Shanghai. The AECOPD patients treated with NIV and admitted to the respiratory department or respiratory intensive care unit were recruited between December 1, 2016, and November 30, 2017.

RESULTS

There were 555 patients finally recruited in this study. The age was 75.8 ± 9.6 years old and 380 patients (68.5%) were male. 70.5% of all patients had respiratory acidosis (pH <7.35). 55.3% of all patients received nebulised bronchodilator and 77.7% were treated with systemic or inhaled corticosteroids during hospitalisation. 525 patients (94.6%) recovered successfully and the mortality was 3.2%. The hospitalisation was 15.3 ± 6.7 days and hospital expenses were 22 911 ± 13 595 RMB. Inadequate and nonstandard drug treatments were the most important problems during management.

CONCLUSION

The NIV can be successfully used for AECOP patients in local hospitals of Shanghai, but accompanied by high costs and long hospital stays. However, the treatments for exacerbation and stable COPD patients are still insufficient.

Neutrophil-to-Lymphocyte Ratio Predicts Clinical Outcome of Severe Acute Exacerbation of COPD in Frequent Exacerbators

Purpose

Frequent exacerbators are a specific phenotype of chronic obstructive pulmonary disease (COPD), whose clinical characteristics and prognostic biomarkers during severe acute exacerbation (AECOPD) have not yet been fully elucidated. The aim of this study was to investigate the clinical features of severe AECOPD in frequent exacerbators and explore the predictive value of the neutrophil-to-lymphocyte ratio (NLR) for outcome in this phenotype during severe exacerbation.

Patients and Methods

A total of 604 patients with severe AECOPD were retrospectively included in the study. Subjects were defined as frequent exacerbators if they experienced two or more exacerbations in the past year. Clinical characteristics and worse outcome (ICU admission, or invasive ventilation, or in-hospital mortality) during severe AECOPD were compared between frequent exacerbators and non-frequent ones. Furthermore, the relationship between NLR and worse outcome in frequent exacerbators was analyzed using logistic regression and receiver operating characteristic (ROC).

Results

Among 604 patients with severe AECOPD, 282 (46.69%) were frequent exacerbators and 322 (53.31%) were non-frequent exacerbators. Compared with the non-frequent ones, frequent exacerbators presented higher levels of NLR (5.93 [IQR, 3.40–9.28] vs 4.41 [IQR, 2.74–6.80]; p<0.001), and more worse outcome incidence (58 [20.57%] vs 38 [11.80%]; p=0.003). Moreover, among the frequent exacerbators, NLR levels in the patients with worse outcome were much higher than in those without worse outcome (11.09 [IQR, 7.74–16.49] vs 5.28 [IQR, 2.93–7.93]; p<0.001). Increased NLR was significantly associated with a higher risk of worse outcome in frequent exacerbators (OR, 1.43; 95% CI, 1.28–1.64; p<0.001). Furthermore, ROC analysis revealed that a cut-off value of 10.23, NLR could predict worse outcome of severe AECOPD in frequent exacerbators (sensitivity 62.1%, specificity 92.0%, AUC 0.833).

Conclusion

Frequent exacerbators exhibited an increased level of NLR and a higher proportion of worse outcome during severe AECOPD. NLR is expected to be a promising predictive biomarker for the prognosis of severe AECOPD in frequent exacerbators.

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

PURPOSE

To explore the relationship between the blood eosinophil concentrations in the early stage and mortality in critically ill patients with acute exacerbation of chronic obstructive pulmonary disease.

METHODS

Patient data were extracted from the MIMIC-III V1.4 database. Only the acute exacerbation of chronic obstructive pulmonary disease patients with the first measurement time of blood eosinophil concentrations (%) between 24 hours before admission and 24 hours after admission was included. The logistic regression model was used to analyze the association between eosinophil and outcomes.

RESULTS

1019 patients were included in the study. Two multivariate regression models were built. The adjusted odds ratio of in-hospital mortality, in-ICU mortality, hospital length of stay and ICU length of stay for initial blood eosinophil concentrations in model 1 (adjusted for SAPS Ⅱ, cardiac arrhythmias, solid tumor, metastatic cancer, liver disease, neutrophils) were 0.792 (95% CI: 0.643-0.976, p=0.028), 0.812 (95% CI: 0.645-1.022, p=0.076), 0.847 (95% CI: 0.772-0.930, p=0.001) and 0.914 (95% CI: 0.836-1.000, p=0.049) respectively. Meanwhile, in model 2 (adjusted for SOFA score, age, cardiac arrhythmias, solid tumor, metastatic cancer, liver disease, neutrophils) ORs were 0.785 (95% CI: 0.636-0.968, p=0.024), 0.807 (95% CI: 0.641-1.016, p=0.068), 0.854 (95% CI: 0.778-0.939, p=0.001) and 0.917 (95% CI: 0.838-1.004, p=0.060) respectively. The area under the ROC curve for eosinophil initial was 0.608 (95% CI: 0.559-0.657). The discriminatory eosinophil thresholds were 0.35% (sensitivity=0.59, specificity=0.61) for in-hospital mortality.

CONCLUSION

Increased blood eosinophils were associated with decreased in-hospital mortality and shorten hospital length of stay in critically ill patients with acute exacerbation of chronic obstructive pulmonary disease. A discriminatory eosinophil threshold of 0.35% for mortality was found, but further studies were needed to verify it.

The lower the eosinophils, the stronger the inflammatory response? The relationship of different levels of eosinophils with the degree of inflammation in acute exacerbation chronic obstructive pulmonary disease (AECOPD)

Background

Blood eosinophil levels are a known marker for the effects of therapy in patients with chronic obstructive pulmonary disease (COPD). This study aimed to clarify the cutoff values for blood eosinophils (EOS) to predict exacerbation risk and prognosis of acute exacerbation COPD (AECOPD) and investigate their correlation using inflammatory indicators and clinical characteristics.

Methods

In this observational study of 174 patients with AECOPD, we assessed the relationship between EOS and COPD. According to the percentage of blood EOS, patients were grouped into two groups (Group 1: EOS <2%, n=98; Group 2: EOS ≥2%, n=76), and Group 2 was further divided into Group A (2%≤ EOS <4%) and Group B (EOS ≥4%) based on a cutoff value of 4%. Patients received standardized treatment after collection of peripheral blood specimen. Associations of EOS with laboratory indicators before any treatment in hospital and with clinical data were compared.

Results

Patients in Group 1 showed significantly severe inflammation, worse pulmonary function, longer length of stay (LOS) (P<0.001), higher mMRC score (P<0.05), higher CAT score (P<0.05), higher rates of mortality (P<0.05), and greater noninvasive mechanical ventilation usage (P<0.05) compared with Group 2. Intriguingly, the CRP, total mMRC and CAT scores of patients in Group A were significantly lower than those in Group B (P<0.001; P<0.01; P<0.05, respectively). Pearson correlation analysis showed that a low percentage blood eosinophil level was negatively associated with higher WBC count (r=–0.155, P<0.05), NLR (r=–0.227, P<0.01) and CRP (r=–0.308, P<0.01).

Conclusions

Different cutoff values for percentage blood EOS might be useful biomarkers for predicting the severity of exacerbation and prognosis of inpatients with AECOPD.

Blood eosinophils and mortality in patients with acute respiratory distress syndrome: A propensity score matching analysis

BACKGROUND

The effect of blood eosinophils (EOSs) on mortality in acute respiratory distress syndrome (ARDS) patients and whether corticosteroids affect this effect are unclear.

METHODS

The Medical Information Mart for Intensive Care III database (version 1.4) was used to extract data. Patients with ARDS were selected for inclusion. Cox regression models using the backward stepwise method and propensity score matching (PSM) were used to assess the relationship between blood EOS counts and 28-day mortality.

RESULTS

A total of 2,567 patients with ARDS were included, and the 28-day mortality rate was 24.19%. The crude 28-day mortality was significantly lower in patients with EOS counts ≥2% (18.60% [85/457] vs. 25.40% [536/2,110], P=0.002) than in those with EOS counts <2%. In the Cox regression model, the EOS counts ≥2% showed a significant association with the decreased 28-day mortality (hazard ratio [HR] 0.731; 95% confidence interval [95% CI] 0.581-0.921, P=0.008). In the corticosteroid non-use subgroup, EOS counts ≥2% was significantly related to decreased 28-day mortality (HR 0.697, 95% CI 0.535-0.909, P=0.008), but the result was not significant in the corticosteroid non-use subgroup model (P=0.860). A total of 457 well-matched pairs were obtained by a 1:1 matching algorithm after PSM. The 28-day mortality remained significantly lower in the EOS counts ≥2% group (18.60% [85/457] vs. 26.70% [122/457], P=0.003).

CONCLUSIONS

Higher EOS counts are related to lower 28-day mortality in ARDS patients, and this relationship can be counteracted by using corticosteroids.

Prediction of non-muscle-invasive bladder cancer recurrence during intravesical BCG immunotherapy by use of peripheral blood eosinophil count and percentage: a preliminary report

OBJECTIVES

To determine whether there is an association between blood eosinophil count and percentage with the recurrence of nonmuscle invasive bladder cancer (NMIBC) during Bacillus Calmette-Guérin (BCG) maintenance therapy with our preliminary results.

METHODS

A total of 53 patients with NMIBC underwent BCG immunotherapy between January 2015 and September 2018, and met our inclusion criteria were included in the study. The parameters age, gender, smoking status, comorbidity, blood neutrophil, lymphocyte and eosinophil counts, blood eosinophil percentage, previous single postoperative intravesical chemotherapy instillation, tumor characteristic, and total and maintenance dose numbers of BCG were extracted from our medical records and compared between patients with response and with recurrence.

RESULTS

Blood eosinophil count and percentage were significantly higher in patients with recurrence compared to patients with response (0.263 ± 0.37 vs. 0.0134 ± 0.021, p = 0.01 and 0.31 ± 0.29 vs. 0.17 ± 0.27, p = 0.01). Other parameters were similar in patients with recurrence and response. Receiver-operating characteristic analysis showed a considerable diagnostic value of blood eosinophil count and percentage in the prediction of bladder cancer recurrence during BCG immunotherapy.

CONCLUSION

Blood eosinophil count and percentage in patients with NMIBC can predict the disease recurrence during the BCG immunotherapy. Our research raised new questions and assumptions about the role of eosinophils during BCG immunotherapy.

Clinical Differences between Eosinophilic and Noneosinophilic Acute Exacerbation of Chronic Obstructive Pulmonary Disease: A Multicenter Cross-Sectional Study

METHODS

A total of 643 AECOPD patients were enrolled in this multicenter cross-sectional study. Finally, 455 were included, 214 in the normal-eosinophil AECOPD (NEOS-AECOPD) group, 63 in the mild increased-eosinophil AECOPD (MEOS-AECOPD) group, and 138 in the severe increased-eosinophil AECOPD (SEOS-AECOPD) group. Demographic data, underlying diseases, symptoms, and laboratory findings were collected. Multiple logistic regression analysis was performed to identify the independent factors associated with blood eosinophils (EOS). Correlations between blood EOS and its associated independent factors were evaluated.

RESULTS

The significant differences in 19 factors, including underlying diseases, clinical symptoms, and laboratory parameters, were identified by univariate analysis. Subsequently, multiple logistic regression analysis revealed that lymphocyte%, neutrophil% (NS%), procalcitonin (PCT), and anion gap (AG) were independently associated with blood EOS in AECOPD. Both blood EOS counts and EOS% were significantly correlated with lymphocyte%, NS%, PCT, and AG.

CONCLUSIONS

Collectively, blood EOS was independently associated with lymphocyte%, NS%, PCT, and AG in AECOPD patients. Lymphocyte% was lower, and NS%, PCT, and AG were higher in eosinophilic AECOPD. Our results indicate that viral-dominant infections are the probable major etiologies of eosinophilic AECOPD. Noneosinophilic AECOPD is more likely associated with bacterial-dominant infections. The systemic inflammation in noneosinophilic AECOPD was more severe.

Senescence in Pulmonary Fibrosis: Between Aging and Exposure

To date, chronic pulmonary pathologies represent the third leading cause of death in the elderly population. Evidence-based projections suggest that >65 (years old) individuals will account for approximately a quarter of the world population before the turn of the century. Genomic instability, telomere attrition, epigenetic alterations, loss of proteostasis, deregulated nutrient sensing, mitochondrial dysfunction, cellular senescence, stem cell exhaustion, and altered intercellular communication, are described as the nine “hallmarks” that govern cellular fitness. Any deviation from the normal pattern initiates a complex cascade of events culminating to a disease state. This blueprint, originally employed to describe aberrant changes in cancer cells, can be also used to describe aging and fibrosis. Pulmonary fibrosis (PF) is the result of a progressive decline in injury resolution processes stemming from endogenous (physiological decline or somatic mutations) or exogenous stress. Environmental, dietary or occupational exposure accelerates the pathogenesis of a senescent phenotype based on (1) window of exposure; (2) dose, duration, recurrence; and (3) cells type being targeted. As the lung ages, the threshold to generate an irreversibly senescent phenotype is lowered. However, we do not have sufficient knowledge to make accurate predictions. In this review, we provide an assessment of the literature that interrogates lung epithelial, mesenchymal, and immune senescence at the intersection of aging, environmental exposure and pulmonary fibrosis.

Induced sputum metabolomic profiles and oxidative stress are associated with chronic obstructive pulmonary disease (COPD) severity: potential use for predictive, preventive, and personalized medicine

Chronic obstructive pulmonary disease (COPD) is a highly heterogeneous disease, and metabolomics plays a hub role in predictive, preventive, and personalized medicine (PPPM) related to COPD. This study thus aimed to reveal the role of induced sputum metabolomics in predicting COPD severity. In this pilot study, a total of 20 COPD patients were included. The induced sputum metabolites were assayed using a liquid chromatography-mass spectrometry (LC-MS/MS) system. Five oxidative stress products (myeloperoxidase (MPO), superoxide dismutase (SOD), glutathione (GSH), neutrophil elastase (NE), and 8-iso-PGF2α) in induced sputum were measured by ELISA, and the metabolomic profiles were distinguished by principal component analysis (PCA) and orthogonal projections to latent structures discriminant analysis (OPLS-DA). The Kyoto Encyclopedia of Genes and Genomes (KEGG) was used for pathway enrichment analysis, and a significant difference in induced sputum metabolomics was observed between moderate and severe COPD. The KEGG analysis revealed that the glycerophospholipid metabolism pathway was downregulated in severe COPD. Due to the critical role of glycerophospholipid metabolism in oxidative stress, significant negative correlations were discovered between glycerophospholipid metabolites and three oxidative stress products (SOD, MPO, and 8-iso-PGF2α). The diagnostic values of SOD, MPO, and 8-iso-PGF2α in induced sputum were found to exhibit high sensitivities and specificities in the prediction of COPD severity. Collectively, this study provides the first identification of the association between induced sputum metabolomic profiles and COPD severity, indicating the potential value of metabolomics in PPPM for COPD management. The study also reveals the correlation between glycerophospholipid metabolites and oxidative stress products and their value for predicting COPD severity.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13167-020-00227-w.

The Value of FENO Measurement for Predicting Treatment Response in Patients with Acute Exacerbation of Chronic Obstructive Pulmonary Disease

Background

Fractional exhaled nitric oxide (FENO) has been shown to be a marker of airway inflammation in various pulmonary diseases, including chronic obstructive pulmonary disease (COPD). In this study, we assessed the FENO level in patients with acute exacerbations of COPD (AECOPD) and analyzed the predictive value of the FENO level for treatment response.

Methods

Demographic data were collected at admission. FENO, lung function, blood gases, COPD Assessment Test (CAT), and modified Medical Research Council (mMRC) scores were measured at admission and on day 7. At the second visit, the patients were asked to report their health status; scores ranged from 1 to 5, representing "much better", "slightly better", "no change", "slightly worse", and "much worse", respectively. The treatment response was evaluated based on the patient's reported health status (responders were those who reported much better and slightly better) and lung function (responders were those who presented an increase in FEV1 over 200 mL).

Results

A total of 182 patients were recruited into the analysis. The FENO level positively correlated with an increase in FEV1 and FEV1% (r = 0.291, p < 0.001 and r = 0.205, p = 0.005, respectively), but negatively correlated with a decrease in the COPD Assessment Test (CAT) score (r = -0.197, p = 0.008) and patient-reported health status (rho = -0.408, p<0.001). An inverse correlation was observed between FENO concentrations at admission and the length of hospital stay. The cut-off point for differentiating responders, identified by health status, was 18 ppb, with the sensitivity being 89.7% and specificity 88.9%.

Conclusion

FENO levels, determined at hospital admission, are potential to predict the overall treatment response in AECOPD patients, including remission in subjective patient-reported health statuses and, also, improvements in lung function.

Registry Number

ChiCTR-ROC-16,009,087 (http://www.chictr.org.cn/).