Relationship between blood and bronchial submucosal eosinophilia and reticular basement membrane thickening in chronic obstructive pulmonary disease

The association of blood eosinophil counts and FEV1 decline: a cohort study

BACKGROUND

Accelerated lung function decline is characteristic of COPD. However, the association between blood eosinophil counts and lung function decline, accounting for current smoking status, in young individuals without prevalent lung disease is not fully understood.

METHODS

This is a cohort study of 629 784 Korean adults without COPD or a history of asthma at baseline who participated in health screening examinations including spirometry and differential white blood cell counts. We used a linear mixed-effects model to estimate the annual change in forced expiratory volume in 1 s (FEV1) (mL) by baseline blood eosinophil count, adjusting for covariates including smoking status. In addition, we performed a stratified analysis by baseline and time-varying smoking status.

RESULTS

During a mean follow-up of 6.5 years (maximum 17.8 years), the annual change in FEV1 (95% CI) in participants with eosinophil counts <100, 100-199, 200-299, 300-499 and ≥500 cells·µL-1 in the fully adjusted model were -23.3 (-23.9--22.7) mL, -24.3 (-24.9--23.7) mL, -24.8 (-25.5--24.2) mL, -25.5 (-26.2--24.8) mL and -26.8 (-27.7--25.9) mL, respectively. When stratified by smoking status, participants with higher eosinophil count had a faster decline in FEV1 than those with lower eosinophil count in both never- and ever-smokers, which persisted when time-varying smoking status was used.

CONCLUSIONS

Higher blood eosinophil counts were associated with a faster lung function decline among healthy individuals without lung disease, independent of smoking status. The findings suggest that higher blood eosinophil counts contribute to the risk of faster lung function decline, particularly among younger adults without a history of lung disease.

How inhaled corticosteroids target inflammation in COPD

Inhaled corticosteroids (ICS) are the most commonly used anti-inflammatory drugs for the treatment of COPD. COPD has been previously described as a "corticosteroid-resistant" condition, but current clinical trial evidence shows that selected COPD patients, namely those with increased exacerbation risk plus higher blood eosinophil count (BEC), can benefit from ICS treatment. This review describes the components of inflammation modulated by ICS in COPD and the reasons for the variation in response to ICS between individuals. There are corticosteroid-insensitive inflammatory pathways in COPD, such as bacteria-induced macrophage interleukin-8 production and resultant neutrophil recruitment, but also corticosteroid-sensitive pathways including the reduction of type 2 markers and mast cell numbers. The review also describes the mechanisms whereby ICS can skew the lung microbiome, with reduced diversity and increased relative abundance, towards an excess of proteobacteria. BEC is a biomarker used to enable the selective use of ICS in COPD, but the clinical outcome in an individual is decided by a complex interacting network involving the microbiome and airway inflammation.

Association between blood eosinophil count and small airway eosinophils in smokers with and without COPD

Introduction

Airway eosinophilic inflammation is a pathological feature in a subgroup of patients with COPD and in some smokers with a high COPD risk. Although blood eosinophil count is used to define eosinophilic COPD, the association between blood eosinophil count and airway eosinophilic inflammation remains controversial. This cross-sectional study tested this association in smokers with and without COPD while considering potential confounders, such as smoking status and comorbidities.

Methods

Lung specimens were obtained from smokers with and without COPD and non-COPD never-smokers undergoing lung lobectomy. Those with any asthma history were excluded. The infiltration of eosinophils into the small airway wall was quantified on histological sections stained with major basic protein (MBP).

Results

The number of airway MBP-positive cells was greater in smokers (n=60) than in never-smokers (n=14). Smokers with and without COPD (n=30 each) exhibited significant associations between blood eosinophil count and airway MBP-positive cells (ρ=0.45 and 0.71). When smokers were divided into the high and low airway MBP groups based on their median value, blood eosinophil count was higher in the high-MBP group, with no difference in age, smoking status, comorbidities, emphysema or coronary artery calcification on computed tomography, and inhaled corticosteroid (ICS) use. The association between greater blood eosinophil count and the high-MBP group was confirmed in multivariable models adjusted for smoking status, airflow limitation and ICS use.

Conclusion

The blood eosinophil count may reflect eosinophilic inflammation in the small airways in smokers with and without COPD.

Novel Anti-Inflammatory Approaches to COPD

Airway inflammation, driven by different types of inflammatory cells and mediators, plays a fundamental role in COPD and its progression. Neutrophils, eosinophils, macrophages, and CD4+ and CD8+ T lymphocytes are key players in this process, although the extent of their participation varies according to the patient's endotype. Anti-inflammatory medications may modify the natural history and progression of COPD. However, since airway inflammation in COPD is relatively resistant to corticosteroid therapy, innovative pharmacological anti-inflammatory approaches are required. The heterogeneity of inflammatory cells and mediators in annethe different COPD endo-phenotypes requires the development of specific pharmacologic agents. Indeed, over the past two decades, several mechanisms that influence the influx and/or activity of inflammatory cells in the airways and lung parenchyma have been identified. Several of these molecules have been tested in vitro models and in vivo in laboratory animals, but only a few have been studied in humans. Although early studies have not been encouraging, useful information emerged suggesting that some of these agents may need to be further tested in specific subgroups of patients, hopefully leading to a more personalized approach to treating COPD.

Inhaled Corticosteroids and Bronchiectasis: Friend or Foe?

The three most common chronic inflammatory airway diseases are asthma, chronic obstructive pulmonary disease (COPD), and bronchiectasis [...].

Biologic therapies for chronic obstructive pulmonary disease

INTRODUCTION

Chronic obstructive pulmonary disease (COPD) is a disorder characterized by a complicated chronic inflammatory response that is resistant to corticosteroid therapy. As a result, there is a critical need for effective anti-inflammatory medications to treat people with COPD. Using monoclonal antibodies (mAbs) to inhibit cytokines and chemokines or their receptors could be a potential approach to treating the inflammatory component of COPD.

AREAS COVERED

The therapeutic potential that some of these mAbs might have in COPD is reviewed.

EXPERT OPINION

No mAb directed against cytokines or chemokines has shown any therapeutic impact in COPD patients, apart from mAbs targeting the IL-5 pathway that appear to have statistically significant, albeit weak, effect in patients with eosinophilic COPD. This may reflect the complexity of COPD, in which no single cytokine or chemokine has a dominant role. Because the umbrella term COPD encompasses several endotypes with diverse underlying processes, mAbs targeting specific cytokines or chemokines should most likely be evaluated in limited and focused populations.

The Microbiome in COPD: Emerging Potential for Microbiome-Targeted Interventions

The aim of interventions over the respiratory microbiome in COPD is to preserve the original microbial flora, focusing in taxa with a demonstrated impact on the prognosis of the disease. Inhaled therapy is the main treatment for COPD, and chronic corticosteroid use is recommended for patients with frequent exacerbations. This therapy, however, increases both the bronchial microbial load and the abundance of potentially pathogenic bacteria in patients with low peripheral eosinophil counts, and to minimize its use in patients without peripheral eosinophilia, when possible, may avoid increases in bacterial loads of microorganisms as Haemophilus influenzae and Streptococcus pneumoniae. In exacerbations antibiotics determine a decrease in the microbial diversity, a change that persists during stability periods in frequent exacerbators. High-diversity bronchial microbiomes are enriched in non-dominant genera and determine low exacerbation frequencies and survival improvement. Limiting the antibiotic use to the treatment of exacerbations which would clearly benefit would favor the diversity of the respiratory microbiome and may have a positive impact on quality of life and survival. Oral antiseptics have shown and effect on the bronchial microbiome that was associated with improvements in quality of life, and the gut microbiome may be also modified through the oral administration of probiotics or prebiotics, that potentially may determine decreases in lung inflammation and bronchial hyperreactivity. High fiber diets also favor the production of anti-inflammatory molecules by the digestive flora, which would reach the respiratory system through the bloodstream. Interventional approaches favoring the preservation of the respiratory microbiome in COPD need first to select accurately the patients who would benefit from long-term inhaled corticosteroids and antibiotic treatments during exacerbations, under the hypothesis that keeping a respiratory microbiome close to the healthy subject would favor the respiratory health. Additionally, high fiber diets may be able to modify the gut microbiome and influence the respiratory system through the gut-lung axis. Therapeutic approaches targeting the microbiome to improve COPD, however, still require clinical validation and the identification of patient subtypes who would benefit the most with their use.

The Role of Dual Bronchodilation and the Conscientious Use of Inhaled Corticosteroid in COPD

Chronic obstructive pulmonary disease (COPD) is a global public health burden that stands out as a leading cause of mortality around the world, especially in less developed countries. COPD treatment should be centered on the individual necessities of each patient, integrating pharmacological therapy, immunization, nutritional support, pulmonary rehabilitation and control of comorbidities. Combining a long-acting antimuscarinic (LAMA) with a long-acting beta2-agonist (LABA) bronchodilator has proven to be more effective than monotherapy with LABA or LAMA, in terms of the functional improvement of forced expiratory volume (FEV1), symptoms and life quality and may be helpful in patients with progressive dyspnea. The eosinophil blood count is a simple biomarker that could guide personalized treatment strategies by identifying patients with greater clinical benefits of inhaled corticosteroid (ICS) treatment. However, one critical concern is the increased risk of pneumonia in individuals treated with ICS.

Blood Eosinophils and Chronic Obstructive Pulmonary Disease: A GOLD Science Committee 2022 Review

COPD is a heterogeneous condition. Some patients benefit from treatment with inhaled corticosteroids (ICS) but this requires a precision medicine approach, based on clinical characteristics (phenotyping) and biological information (endotyping) in order to select patients most likely to benefit. The GOLD 2019 report recommended using exacerbation history combined with blood eosinophil counts (BEC) to identify such patients. Importantly, the relationship between BEC and ICS effects is continuous; no / small effects are observed at lower BEC, with increasing effects at higher BEC. The GOLD 2022 report has added additional evidence and recommendations concerning the use of BEC in COPD in clinical practice. Notably, associations have been demonstrated in COPD patients between higher BEC and increased levels of type-2 inflammation in the lungs. These differences in type-2 inflammation can explain the differential ICS response according to BEC. Additionally, lower BEC are associated with greater presence of proteobacteria, notably haemophilus, and increased bacterial infections and pneumonia risk. These observations support management strategies that use BEC to help identify subgroups with increased ICS response (higher BEC) or increased risk of bacterial infection (lower BEC). Recent studies in younger individuals without COPD have also shown that higher BEC are associated with increased risk of FEV1 decline and the development of COPD. Here we discuss and summarise the GOLD 2022 recommendations concerning the use of BEC as a biomarker that can facilitate a personalised management approach in COPD.

An Overview of the Safety and Efficacy of Monoclonal Antibodies for the Chronic Obstructive Pulmonary Disease

Several mAbs have been tested or are currently under clinical evaluation for the treatment of COPD. They can be subdivided into those that aim to block specific pro-inflammatory and pro-neutrophilic cytokines and chemokines, such as TNF-α, IL-1β, CXCL8 and IL-1β, and those that act on T2-mediated inflammation, respectively, by blocking IL-5 and/or its receptor, preventing IL-4 and IL-13 signaling, affecting IL-33 pathway and blocking TSLP. None of these approaches has proved to be effective, probably because in COPD there is no dominant cytokine or chemokine and, therefore, a single mAb cannot be effective on all pathways. With a more in-depth understanding of the numerous pheno/endotypic pathways that play a role in COPD, it may eventually be possible to identify those specific patients in whom some of these cytokines or chemokines might predominate. In this case, it will be possible to implement a personalized treatment, but the use of each mAb will only be reserved for a very limited number of subjects.

Blood eosinophil counts and the development of obstructive lung disease: the Kangbuk Samsung Health Study

The impact of blood eosinophil counts on the development of chronic obstructive lung disease (COPD) is unknown. We investigated whether a higher blood eosinophil counts was associated with the risk of developing obstructive lung disease (OLD) in a large cohort of men and women free lung disease at baseline.Cohort study of 359 456 Korean adults without a history of asthma and without OLD at baseline who participated in health screening exams including spirometry. OLD was defined as pre-bronchodilator FEV₁/FVC<0.7 and FEV₁<80% predicted.After a median follow-up of 5.6 years (interquartile range, 2.9-9.2), 5008 participants developed incident OLD (incidence rate, 2.1 per 1000 person-years; 95% CI, 2.1-2.2). In the fully-adjusted model, the HR (95% CI) for incident OLD comparing eosinophil counts of 100-<200, 200-<300, 300-<500 and ≥500 cells·μL^-1 to <100 cells·μL^-1 were 1.07 (1.00-1.15), 1.30 (1.20-1.42), 1.46 (1.33-1.60) and 1.72 (1.51-1.95) (p for trend <0.001). These associations were consistent in clinically relevant subgroups, including never, former, and current smokers.In this large longitudinal cohort study, blood eosinophil counts were positively associated with the risk of developing of OLD. Our findings indicate a potential role of eosinophil count as an independent risk factor for developing COPD.

Prospects for COPD treatment

The management of chronic obstructive pulmonary disease (COPD) is fundamentally still heavily dependent on the use of bronchodilators and corticosteroids. Therefore, there is a need for alternative, more effective and safer therapeutic approaches. In particular, since inflammation in COPD lungs is often poorly responsive to corticosteroid treatment, novel pharmacological anti-inflammatory approaches are needed to optimally treat COPD patients. There have been multiple attempts to develop drugs that inhibit recruitment and activation of inflammatory cells, such as macrophages, neutrophils and T-lymphocytes, in the lungs of patients with COPD or target inflammatory mediators that are important in the recruitment or activation of these inflammatory cells or released by such cells. This review article focuses on novel classes of anti-inflammatory drugs that have already been tested in humans as possible treatments for patients with COPD.

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.

Role of Type2 Inflammatory Biomarkers in Chronic Obstructive Pulmonary Disease

Airway inflammation in chronic obstructive pulmonary disease (COPD) is typically thought to be driven by Type1 immune responses, while Type2 inflammation appears to be present in definite proportions in the stable state and during exacerbations. In fact, some COPD patients showed gene expression of Type2 inflammation in the airway, and this subset was associated with the inhaled corticosteroid (ICS) response. Interestingly enough, the relationship between COPD and diseases associated with Type2 inflammation from the perspective of impaired lung development is increasingly highlighted by recent epidemiologic studies on the origin of COPD. Therefore, many researchers have shown an interest in the prevalence and the role of existent Type2 biomarkers such as sputum and blood eosinophils, exhaled nitric oxide fraction, and atopy, not only in asthma but also in COPD. Although the evidence about Type2 biomarkers in COPD is inconsistent and less robust, Type2 biomarkers have shown some potential when analyzing various clinical outcomes or therapeutic response to ICS. In this article, we review the existent and emerging Type2 biomarkers with clinically higher applicability in the management of COPD.

Endo-phenotyping of COPD patients

INTRODUCTION

Chronic obstructive pulmonary disease (COPD) is a heterogeneous syndrome and may comprise several different phenotypes that are driven by different molecular mechanisms (endotypes). Several different clinical, genetic, and inflammatory phenotypes of COPD have been recognized and this may lead to more precise effective therapies.

AREAS COVERED

The different clinical phenotypes, including smoking versus nonsmoking COPD, small airway disease versus emphysema, non-exacerbators versus frequent exacerbators are discussed. Rare genetic endotypes (alpha₁-antitrypsin deficiency, telomerase polymorphisms), and inflammatory phenotypes (eosinophilic versus neutrophilic) are also recognized in stable and exacerbating patients and have implications for the choice of therapy.

EXPERT OPINION

Clinical phenotypes have so far not proved to be very useful in selecting more personalized therapy for COPD. Even with genetic endotypes, this has not led to improved therapy. More promising is the recognition that COPD patients who have increased sputum or blood eosinophils tend to have more frequent exacerbations and inhaled corticosteroids are more effective in preventing exacerbation. Increased blood eosinophils have proved to be a useful biomarker now used to target ICS more effectively. Furthermore, COPD patients with low eosinophils are more likely to get pneumonia with ICS and to have lower airway bacterial colonization.

The stability of blood eosinophils in stable chronic obstructive pulmonary disease: a retrospective study in Belgian primary care

Background

Blood eosinophil counts (BEC) were recently included in the 2019 Global Initiative for Obstructive Lung Disease (GOLD) guideline as an easily accessible theragnostic biomarker for Chronic Obstructive Pulmonary Disease (COPD). However, the stability of BEC remains insufficiently studied.

Methods

We conducted a retrospective study in six primary care practices in Belgium on data from Electronic Health Records of stable COPD patients, to characterise the stability of blood eosinophils over time. We report the percentage of patients with BEC persistently below or above the 2019 GOLD guideline thresholds (100 and 300 cells/μL). For each patient the mean, standard deviation (SD) and relative standard deviation (RSD) of the BEC were calculated to determine the intra-patient variability.

Results

Ninety-eight patients were included, yielding 1082 eosinophil measurements (median 8 measurements/patient), with BEC ranging between 0 and 1504 cells/μL. Four (4.1%) patients had BEC persistently below 100 cells/μL, 34 (34.7%) had measurements persistently above this threshold. Approximately half of the patients (51.0%) had BEC persistently below 300 cells/μL and 3 (3.1%) patients had counts persistently above this threshold. 28.6% of patients crossed both threshold values throughout the registration period. The mean BEC per patient ranged between 15 and 846 cells/μL with an intra-patient SD between 5 and 658 cells/μL. The mean intra-patient RSD was 0.46. There was a significant strong positive correlation (Pearson analyses) between the mean BEC and SD (r = 0.765; n = 98). Simple linear regression was used to further describe the influence of the mean eosinophil count on the SD (B = 0.500; 95%CI 0.415–0.586; n = 98; p < 0.001).

Conclusion

BEC can be variable in individual COPD patients. Therefore, the use of a single measurement to guide therapeutic decisions remains debatable. Further prospective research remains necessary to validate the reproducibility of this biomarker.

Frequency of Blood Eosinophilia in newly diagnosed Chronic Obstructive Pulmonary Disease patients

Objective:

To determine Blood Eosinophilia frequency in newly diagnosed Chronic Obstructive Pulmonary Disease patients.

Methods:

An observational cross-sectional research on newly diagnosed COPD patients with age ≥ 40 years was performed at Ojha Institute of Chest Diseases, Dow University of Health Sciences Karachi. COPD patients diagnosed in outpatient clinic or admitted in Chest Unit during six-month period from September 2018 to May 2019 were selected. Each patient underwent spirometry, and blood was tested for eosinophilia (≥ 2% eosinophils in blood), after obtaining informed consent and clinical history.

Results:

One hundred and fifty COPD patients were diagnosed and evaluated for Blood Eosinophilia, out of which 86 (57.3%) and 64 (42.7%) patients were Males and Females respectively with mean age of 63.72 ± 10.24 years. Current Smokers were 48 (32.0%), Ex-Smokers 15 (10.0%), and Biomass Exposure was present in 76 (50.7%) of patients. Spirometric severity of COPD was Mild in 11 (7.3%), Moderate in 68 (45.3%), Severe in 59 (39.3%), and Very Severe in 12 (8.0%) patients. Blood Eosinophilia was present in 59 (39.3%) patients of COPD among which majority 43 (72.9%) were having Moderate 24 (40.7%) and Severe 19 (32.2%) COPD respectively.

Conclusion:

Frequency of Blood Eosinophilia in newly diagnosed COPD patients was high, among which most of the COPD patients were moderate to severe.

Eosinophils, basophils and type 2 immune microenvironments in COPD-affected lung tissue

Although elevated blood or sputum eosinophils are present in many patients with COPD, uncertainties remain regarding the anatomical distribution pattern of lung-infiltrating eosinophils. Basophils have remained virtually unexplored in COPD. This study mapped tissue-infiltrating eosinophils, basophils and eosinophil-promoting immune mechanisms in COPD-affected lungs.

Surgical lung tissue and biopsies from major anatomical compartments were obtained from COPD patients with severity grades Global Initiative for Chronic Obstructive Lung Disease stages I–IV; never-smokers/smokers served as controls. Automated immunohistochemistry and in situ hybridisation identified immune cells, the type 2 immunity marker GATA3 and eotaxins (CCL11, CCL24).

Eosinophils and basophils were present in all anatomical compartments of COPD-affected lungs and increased significantly in very severe COPD. The eosinophilia was strikingly patchy, and focal eosinophil-rich microenvironments were spatially linked with GATA3⁺ cells, including type 2 helper T-cell lymphocytes and type 2 innate lymphoid cells. A similarly localised and interleukin-33/ST2-dependent eosinophilia was demonstrated in influenza-infected mice. Both mice and patients displayed spatially confined eotaxin signatures with CCL11⁺ fibroblasts and CCL24⁺ macrophages.

In addition to identifying tissue basophilia as a novel feature of advanced COPD, the identification of spatially confined eosinophil-rich type 2 microenvironments represents a novel type of heterogeneity in the immunopathology of COPD that is likely to have implications for personalised treatment.

Highly localised Th2- and eosinophil-rich pockets were identified in COPD-affected lungs, which increased in number with increasing disease severity and included basophils. This exemplifies a novel type of heterogeneity in the immunopathology of COPD.http://bit.ly/2HexTco

Blood Eosinophil Counts in Chronic Obstructive Pulmonary Disease: A Biomarker of Inhaled Corticosteroid Effects

Blood eosinophil counts have emerged as a chronic obstructive pulmonary disease (COPD) biomarker that predict the effects of inhaled corticosteroids (ICS) in clinical practice. Post-hoc and prospective analysis of randomized control trials have shown that higher blood eosinophil counts at the start of the study predict a greater response to ICS. COPD patients with frequent exacerbations (2 or more moderate exacerbations/yr) or a history of hospitalization have a greater response to ICS. Ex-smokers also appear to have a greater ICS response. Blood eosinophil counts can be combined with clinical information such as exacerbation history and smoking status to enable a precision medicine approach to the use of ICS. Higher blood eosinophil counts are associated with increased eosinophilic lung inflammation, and other biological features that may contribute to the increased ICS response observed. Emerging data indicates that lower blood eosinophil counts are associated with an increased risk of bacterial infection, suggesting complex relationships between eosinophils, ICS response, and the airway microbiome.

Relationship of Blood Eosinophils with Fractional Exhaled Nitric Oxide and Pulmonary Function Parameters in Chronic Obstructive Pulmonary Disease (COPD) Exacerbation

BACKGROUND The 2018 Global Initiative for Chronic Obstructive Lung Disease Report reveals that the blood eosinophil count could forecast the risk of flare-ups. This study explored the correlations of blood eosinophils with fractional exhaled nitric oxide (FeNO) and pulmonary function parameters in acute exacerbation of chronic obstructive pulmonary disease (AECOPD). MATERIAL AND METHODS The data of patients with AECOPD at our hospital admitted between July 2018 and June 2019 were retrospectively analyzed. All patients were stratified into an eosinophilic group (≥2%) or a noneosinophilic group (<2%) based on the peripheral eosinophil count per centum. Cross-sectional analysis was performed to compare clinical characteristics, percentage of eosinophils, FeNO, and pulmonary function between the 2 groups. RESULTS After applying the inclusion/exclusion criteria, 247 patients were included. FeNO values were higher in eosinophilic group (n=97) than in noneosinophilic group (n=150) (P=0.005). The forced expiratory volume in 1 second% predicted (FEV1% predicted), FEV1, and forced vital capacity (FVC) were higher in the eosinophilic group than in the noneosinophilic group (P=0.043; P=0.040; and P=0.011, respectively). Blood eosinophilia showed positive correlations with FeNO (P=0.004) and spirometry variables (FEV₁ [% predicted], P=0.003; FEV₁, P<0.001; and FVC, P<0.001). An FeNO level of 22.5 ppb was the best cutoff value to predict blood eosinophilia (P=0.000). CONCLUSIONS Blood eosinophil count is a likely biomarker that can predict positive relationship with FeNO values and pulmonary function parameters.

[Study of the role of blood eosinophil count in patients with severe acute exacerbation of chronic obstructive pulmonary disease hospitalized in a Tunisian Center]

Introduction

There is a controversy over the relationship between blood eosinophil count (BEC) and the severity of chronic obstructive pulmonary disease (COPD) exacerbations. The purpose of our study was to determine the relationship between blood eosinophil count and multiple parameters in assessing the severity of serious acute exacerbation (AE) of obstructive pulmonary disease.

Methods

We conducted a retrospective monocentric study of hospitalized patients with obstructive pulmonary disease treated between 2005 and 2015. We compared 2 groups of patients: G1(BEC+): BEC ≥ 200 cell/μl (103 cases, 20.4%), G2(BEC-): BEC < 200 cell/μl (403 patients: 79.6%).

Results

A total of 506 subjects with obstructive pulmonary disease were included in the study. No significant difference between the two groups in age, gender, forced expiratory volume in one second (FEV1), and the number of AE/year (BEC+: 2.6, BEC-:2.5 AE/year; p = 0.48) was found. The analysis of the parameters of severity of serious AE showed no difference between the two groups in partial pressure of oxygen PaO2 measured on admission (60.5, 59.2 mmHg; p = 0.26), capnia (p=0.57), pH (p=0.74), C-reactive protein rate (mg/L) (82.7, 81; p = 0.89), leukocytosis (p = 0.36), non-invasive mechanical ventilation (5.8%, 6.5%; p = 0.81), invasive mechanical ventilation (p = 0.5),length of stay in hospital (9.7, 9 days; p = 0.21), mean time to next AECOPD (p = 0.32). Survival at 1 year was comparable between the two groups (94% vs 96%; Log Rank: 0.708).

Conclusion

Increased BEC in patients with COPD does not appear to have a negative effect on patients with severe AE. Despite the recent guidelines recommend to consider blood eosinophil count while making treatment decisions, the role and the prognostic interest of blood eosinophil count in patients with COPD could be population-dependent.

Blood eosinophils as biomarkers of therapeutic response to chronic obstructive pulmonary disease: Still work in progress

Disease phenotyping is a key step towards an increasingly personalized approach to chronic obstructive pulmonary disease (COPD), leading to a more precise assessment, treatment and definition of disease outcomes. The search for biomarkers able to guide the identification of COPD phenotypes are of great importance for both researchers and clinicians. However, while several biomarkers of inflammation [e.g., peripheral blood eosinophils and fractional expired nitric oxide] have been identified and applied in asthma, none has been successfully linked to discrete clinical parameters of COPD such as exacerbations, natural progression, and treatment response or mortality risk. Recently, several studies have shown that blood eosinophils are a potential biomarker for patient subset stratification in COPD therapy. Here we reviewed the value of blood eosinophils in predicting the response of COPD patients to treatment.

Blood eosinophils could be useful as a biomarker in chronic obstructive pulmonary disease exacerbations

Introduction The aim of analysing the usefulness of the blood eosinophil count (BEC) as a prognostic marker in exacerbations of patients with Chronic Obstructive Pulmonary Disease (COPD), evaluating its relationship with hospital mortality, the length of stay and the early and late re-admissions. Materials and Methods We have carried out a retrospective study including all patients who required hospital admission from 1 January 2008 to 31 December 2009, with a diagnosis on hospital discharge of COPD exacerbation. These patients were classified using three cut-off points of BEC: less than 200 vs ≥ 200/µL, less than 300 vs ≥ 300/µL and less than 400 vs ≥ 400/µL. Results There were a total of 1626 hospital admissions during the study period with the diagnosis of exacerbation of COPD. In this study we have included 358 patients. The probability of any late re-admission increased with a BEC ≥ 300/µL (odds ratio: 1.684) and for those with a BEC ≥ 400/µL (odds ratio: 2.068). The BEC does not appear to be related to hospital mortality or the probability of early re-admission after an exacerbation of COPD. Conclusions In our study an elevated BEC is associated with a higher incidence of late hospital readmissions in COPD exacerbations.

Predicting response to benralizumab in chronic obstructive pulmonary disease: analyses of GALATHEA and TERRANOVA studies

BACKGROUND

Benralizumab did not significantly reduce exacerbations compared with placebo in the phase 3 GALATHEA and TERRANOVA trials of benralizumab for patients with chronic obstructive pulmonary disease (COPD). We aimed to identify clinical and physiological characteristics of patients with COPD that could help to identify people who are likely to have the greatest treatment effect with benralizumab.

METHODS

We analysed individual study and pooled results from GALATHEA and TERRANOVA. At study enrolment, patients from GALATHEA and TERRANOVA were aged 40-85 years, had moderate to very severe airflow limitation, had elevated blood eosinophil counts, and at least two exacerbations or one severe exacerbation in the previous year despite dual inhaled therapy (inhaled corticosteroids plus long-acting β₂-agonists or long-acting β₂-agonists plus long-acting muscarinic antagonists) or triple inhaled therapy (inhaled corticosteroids plus long-acting β₂-agonists plus long-acting muscarinic antagonists). We analysed data for 3910 patients who received benralizumab (30 mg or 100 mg subcutaneously every 8 weeks; first three doses every 4 weeks) or placebo with dual or triple therapy to identify factors consistently associated with annual exacerbation rate reduction. We evaluated the annual exacerbation rate for benralizumab versus placebo as the primary endpoint. GALATHEA and TERRANOVA are registered with ClinicalTrials.gov, NCT02138916 and NCT02155660, respectively.

FINDINGS

For 2665 patients with elevated blood eosinophil counts, treatment effect with benralizumab every 8 weeks at 100 mg, but not at 30 mg, occurred for patients with a history of more frequent exacerbations, poorer baseline lung function, or greater baseline lung function improvement with short-acting bronchodilators. Patients with baseline blood eosinophil counts of 220 cells per μL or greater with: three or more exacerbations in the previous year receiving benralizumab every 8 weeks versus placebo, had rate ratios (RRs) of 0·69 (95% CI 0·56-0·83) for 100 mg and 0·86 (0·71-1·04) for 30 mg; postbronchodilator FEV₁ of less than 40% had RRs of 0·76 (0·64-0·91) for 100 mg and 0·90 (0·76-1·06) for 30 mg; and postbronchodilator response of at least 15% had RRs of 0·67 (0·54-0·83) for 100 mg and 0·87 (0·71-1·07) for 30 mg. When combined factors were examined, patients with elevated baseline blood eosinophil counts, with three or more exacerbations in the previous year, and who were receiving triple therapy were identified as likely to benefit from benralizumab 100 mg every 8 weeks versus placebo (RR 0·70 [95% CI 0·56-0·88]). Benralizumab 30 mg every 8 weeks did not benefit patients meeting these criteria compared with placebo (RR 0·99 [95% CI 0·79-1·23]).

INTERPRETATION

Elevated blood eosinophil counts combined with clinical characteristics identified a subpopulation of patients with COPD who had reductions in exacerbations with benralizumab treatment. These hypothesis-generating analyses identified the potential efficacy of benralizumab 100 mg for this subpopulation. These findings require prospective evaluation in clinical trials.

FUNDING

AstraZeneca.

Inflammatory endotypes in COPD

Chronic obstructive pulmonary disease (COPD) is a major global health problem that is poorly treated by current therapies as it has proved difficult to treat the underlying inflammation, which is largely corticosteroid-resistant in most patients. Although rare genetic endotypes of COPD have been recognized, despite the clinical heterogeneity of COPD, it has proved difficult to identify distinct inflammatory endotypes. Most patients have increased neutrophils and macrophages in sputum, reflecting the increased secretion of neutrophil and monocyte chemotactic mediators in the lungs. However, some patients also have increased eosinophils in sputum and this may be reflected by increased blood eosinophils. Increased blood and sputum eosinophils are associated with more frequent exacerbations and predict a good response to corticosteroids in reducing and treating acute exacerbations. Eosinophilic COPD may represent an overlap with asthma but the mechanism of eosinophilia is uncertain as, although an increase in sputum IL-5 has been detected, anti-IL-5 therapies are not effective in preventing exacerbations. More research is needed to link inflammatory endotypes to clinical manifestations and outcomes in COPD and in particular to predict response to precision medicines.

Combined allergic rhinitis and asthma syndrome (CARAS)

Combined allergic rhinitis and asthma syndrome (CARAS) is a concept of "one airway - one disease" or "unified airway disease ". The upper and lower airway inflammation characterizes allergic rhinitis and asthma, respectively and both diseases have shown an intimate connection in their genesis, coexistence and similarities as triggered by the same etiological agents; the same inflammatory cell profile and share therapeutic treatment. This review highlights the concept of CARAS by its phenotype, endotype and biomarker classification. Indeed, rhinitis is divided into four major phenotypes: allergic rhinitis; infectious rhinitis; non-infective/non-allergic rhinitis and mixed rhinitis. On the other hand, asthma has no common consensus yet; however, the most accepted classification is based on the stage of life (early- or late- onset asthma) in which the clinical symptoms are presented. Experimental researches where animals develop a syndrome similar to CARAS have been contributed to better understand the pathogenesis of the syndrome. Therefore, the aim of this review is to clarify current terms related to CARAS as definition, phenotypes, endotypes/biomarkers, physiopathology and treatments.

Global Strategy for the Diagnosis, Management, and Prevention of Chronic Obstructive Lung Disease: the GOLD science committee report 2019

Precision medicine is a patient-specific approach that integrates all relevant clinical, genetic and biological information in order to optimise the therapeutic benefit relative to the possibility of side-effects for each individual. Recent clinical trials have shown that higher blood eosinophil counts are associated with a greater efficacy of inhaled corticosteroids (ICSs) in chronic obstructive pulmonary disease (COPD) patients. Blood eosinophil counts are a biomarker with potential to be used in clinical practice, to help target ICS treatment with more precision in COPD patients with a history of exacerbations despite appropriate bronchodilator treatment.The Global Initiative for Chronic Obstructive Lung Disease (GOLD) 2017 pharmacological treatment algorithms, based on the ABCD assessment, can be applied relatively easily to treatment-naive individuals at initial presentation. However, their use is more problematic during follow-up in patients who are already on maintenance treatment. There is a need for a different system to guide COPD pharmacological management during follow-up.Recent large randomised controlled trials have provided important new information concerning the therapeutic effects of ICSs and long-acting bronchodilators on exacerbations. The new evidence regarding blood eosinophils and inhaled treatments, and the need to distinguish between initial and follow-up pharmacological management, led to changes in the GOLD pharmacological treatment recommendations. This article explains the evidence and rationale for the GOLD 2019 pharmacological treatment recommendations.

Engineering Biomimetic Gelatin Based Nanostructures as Synthetic Substrates for Cell Culture

There is a need for synthetic substrates that replicate the natural environment for in vitro intestinal models. Electrospinning is one of the most versatile and cost-effective techniques to produce nanofibrous scaffolds mimicking the basement membrane topography. In this study, three different novel electrospun nanofibrous scaffolds made of a polycaprolactone (PCL), gelatin, and poloxamer 188 (P188) blend were produced and compared with PCL and PCL/gelatin fibers produced using the same solvent system and electrospinning parameters. Each polymer solution used in this experiment was electrospun at four different voltages to study its influence on fiber diameter. The morphology and physical characteristics of the fibers were studied using scanning electron microscopy and atomic force microscopy. The average fiber diameter of all scaffolds was within 200–600 nm and no significant decrease in diameter with an increase in voltage was observed. Attenuated total reflection Fourier transform infrared spectroscopy was used to determine the chemical characteristics of the nanofibrous scaffold. The conductivity of the polymer solutions was also analyzed. Biocompatibility of the scaffolds was determined by a cell proliferation study performed using colorectal carcinoma (Caco-2) cells. PCL/gelatin/P188 scaffolds exhibited higher cell proliferation compared to PCL, PCL/gelatin scaffolds, and the control (tissue culture multi-well plate) with PCL/gelatin/P188 80:10:10 sample showing the highest cell proliferation.

Electrospun Nanometer to Micrometer Scale Biomimetic Synthetic Membrane Scaffolds in Drug Delivery and Tissue Engineering: A Review

The scaffold technology research utilizes biomimicry to produce efficient scaffolds that mimic the natural cell growth environment including the basement membrane for tissue engineering. Because the natural basement membrane is composed of fibrillar protein networks of nanoscale diameter, the scaffold produced should efficiently mimic the nanoscale topography at a low production cost. Electrospinning is a technique that can achieve that. This review discusses the physical and chemical characteristics of the basement membrane and its significance on cell growth and overall focuses on nanoscale biomimetic synthetic membrane scaffolds primarily generated using electrospinning and their application in drug delivery and tissue engineering.

Blood eosinophils and inhaled corticosteroids in patients with COPD: systematic review and meta-analysis

Background

COPD is a highly heterogeneous disease. Potential biomarkers to identify patients with COPD who will derive the greatest benefit from inhaled corticosteroid (ICS) treatment are needed. Blood eosinophil count can serve as a predictive biomarker for the efficacy of ICS treatment. The aim of this systematic review and meta-analysis was to assess whether a blood eosinophil count of ≥2% in patients undergoing ICS therapy was associated with a greater reduction in COPD exacerbation rate and pneumonia incidence.

Materials and methods

An electronic search was performed using the keywords "COPD", "eosinophil", and "clinical trial" in the PubMed and EMBASE databases to retrieve articles, up to 2017, relevant to our focus. Data were extracted, and a meta-analysis was conducted using RevMan 5 (version 5.3.5).

Results

Five studies comprising 12,496 patients with moderate-to-very severe COPD were included. At baseline, 60% of the patients had ≥2% blood eosinophils. Our meta-analysis showed a 17% reduction in exacerbation of moderate/severe COPD in patients with ≥2% blood eosinophils undergoing ICS therapy compared to the non-ICS/ICS withdrawal/placebo group. The difference between the two types of treatment was significant (risk ratio [RR], 0.816; 95% CI, 0.67-0.99; P=0.03). Furthermore, the risk of pneumonia-related events was significantly increased in the subgroup with eosinophil count ≥2% undergoing ICS-containing treatments (RR, 1.969; 95% CI, 1.369-2.833; P<0.001). There was no significant difference in the subgroup with eosinophil count <2% (RR, 1.29; 95% CI, 0.888-1.879; P<0.181).

Conclusion

The results of our meta-analysis suggest that the 2% threshold for blood eosinophils could accurately predict ICS treatment response in patients with COPD, but increased the risk of pneumonia.

Chronic Rhinitis Is a High-Risk Comorbidity for 30-Day Hospital Readmission of Patients with Asthma and Chronic Obstructive Pulmonary Disease

BACKGROUND

Early hospital readmissions for asthma and chronic obstructive pulmonary disease (COPD), measured as hospital readmission within 30 days from the last discharge, is a major economic burden to our health care system. The association of this measure with comorbid chronic rhinitis (CR) has not been investigated before despite significant clinical association between CR and asthma or COPD.

OBJECTIVE

To investigate the association of CR with the risk of asthma or COPD-related early hospital readmission rates.

METHODS

This retrospective cohort study was performed using the asthma- and COPD-related hospital encounter and patient comorbidity data between June 15, 2012, and July 19, 2017, from a large hospital care system in Cincinnati, Ohio. Patients (any sex, race or socioeconomic status, and of all ages) with a primary discharge diagnosis of asthma (n = 4754 patients, 10,111 encounters) and COPD (n = 2176 patients, 4748 encounters) based on International Classification of Diseases, Tenth Revision, Clinical Modification (ICD-10-CM) codes were included. Relevant comorbidities, including comorbid allergic rhinitis (AR) or nonallergic rhinitis (NAR), in such patients were identified using ICD-10-CM codes. The association between 30-day asthma or COPD-related hospital readmission (1670 such encounters for asthma and 736 for COPD) and comorbid CR in the affected patients were determined using Cox proportional hazards models. Multivariate-adjusted hazard ratios (HRs), adjusted for relevant patient comorbidities, compared 30-day asthma- and COPD-related readmissions of patients with CR with those patients without a CR diagnosis.

RESULTS

Analysis was performed on 4754 patients with asthma and 2176 patients with COPD. The median follow-up period (+interquartile range) for asthma was 980 (+760) days and for COPD was 553 (+827) days. The HRs for 30-day asthma- or COPD-related readmission rates were significantly higher in patients with AR (HR = 4.4 [3.9, 5.0] and 2.4 [1.7, 3.2], respectively) or NAR (HR = 3.7 [2.9, 4.9] and 2.6 [1.8, 3.7], respectively) compared with patients without rhinitis. For asthma, both AR and NAR had higher HRs compared with all other comorbidities analyzed. For COPD, both AR and NAR had HRs to the magnitude as obesity and hypertension.

CONCLUSIONS

Comorbid CR is significantly associated with 30-day asthma- and COPD-related readmissions. These findings are useful for guiding health care professionals to focus on outpatient management of both the upper and lower respiratory tracts to reduce early readmission of patients with asthma and COPD.

Current controversies in the stepping up and stepping down of inhaled therapies for COPD at the patient level

The implementation of potential new step-up or step-down treatment recommendations in response to current guidelines is one of the main challenges currently faced in actual daily practice settings. In the present narrative review, we aim to discuss the relevance of these step-up and step-down proposals at the patient level in daily clinical practice. In particular, we aim to review the challenges associated with inhaled maintenance therapy for chronic obstructive pulmonary disease (COPD) in four clinical scenarios. First, we discuss the step up from single to double bronchodilation, including current controversies regarding the addition of a second bronchodilator versus initial treatment with two bronchodilators. Second, we discuss the step up from double bronchodilation to triple therapy while challenging current indications for inhaled steroid therapy and discussing triple therapy designs. Third, we discuss the step down from triple therapy to double bronchodilation while evaluating the effect of this downshift in risk categories on the patient according to the new classifications. Finally, we discuss the step down from double to single bronchodilation, with a special focus on safety. We believe this review will help to highlight the most relevant discussion points regarding the treatment of COPD in a manner that will stimulate and guide related clinical research.

Definition and diagnosis of asthma-COPD overlap (ACO)

It is now widely recognized that asthma and COPD can coexist as asthma-COPD overlap (ACO), but the preliminary attempts at providing universal guidelines for the diagnosis of ACO still need to be improved. We believe that a case can be made for devising guidelines for the diagnosis of this increasingly common disease that are specific to Japan. In this paper, we present our consensus-based description of ACO which we believe is realistic for use in our country. In addition, we cite the scientific evidence for our own "objective" features used to develop the criteria for COPD and asthma diagnosis. We acknowledge that they will need to be validated and updated over time, but hope the results will encourage further research on the characteristics and treatment of this commonly encountered clinical problem.

Role of eosinophils in airway inflammation of chronic obstructive pulmonary disease

COPD is a significant cause of morbidity and mortality. In some patients with COPD, eosinophils contribute to inflammation that promotes airway obstruction; approximately a third of stable COPD patients have evidence of eosinophilic inflammation. Although the eosinophil threshold associated with clinical relevance in patients with COPD is currently subject to debate, eosinophil counts hold potential as biomarkers to guide therapy. In particular, eosinophil counts may be useful in assessing which patients may benefit from inhaled corticosteroid therapy, particularly regarding exacerbation prevention. In addition, several therapies targeting eosinophilic inflammation are available or in development, including monoclonal antibodies targeting the IL5 ligand, the IL5 receptor, IL4, and IL13. The goal of this review was to describe the biologic characteristics of eosinophils, their role in COPD during exacerbations and stable disease, and their use as biomarkers to aid treatment decisions. We also propose an algorithm for inhaled corticosteroid use, taking into consideration eosinophil counts and pneumonia history, and emerging eosinophil-targeted therapies in COPD.

Eosinophilia and clinical outcome of chronic obstructive pulmonary disease: a meta-analysis

Numerous studies have investigated the association between eosinophilia and clinical outcome of patients with chronic obstructive pulmonary disease (COPD) but the evidence is conflicting. We conducted a pooled analysis of outcome measures comparing eosinophilic and non-eosinophilic COPD patients. We searched articles indexed in four databases using Medical Subject Heading or Title and Abstract words including COAD, COPD, eosinophil, eosinophilia, eosinopenia from inception to December 2016. Observational studies and randomized controlled trials with parallel groups comparing COPD patients with and without eosinophilia were included. Comparing to the non-eosinophilic group, those with eosinophilic COPD had a similar risk for exacerbation in 12 months [Odds ratio = 1.07, 95% confidence interval (CI) 0.86–1.32, P = 0.55] and in-hospital mortality [OR = 0.52, 95% CI 0.25–1.07]. Eosinophilia was associated with reduced length of hospital stay (P = 0.04). Subsequent to therapeutic interventions, eosinophilic outpatients performed better in pulmonary function tests [Mean Difference = 1.64, 95% CI 0.05–3.23, P < 0.001]. Inclusion of hospitalized patients nullified the effect. Improvement of quality of life was observed in eosinophilic subjects [Standardized Mean Difference = 1.83, 95% CI 0.02–3.64, P = 0.05], independent of hospitalization status. In conclusion, blood eosinophilia may be predictive of favorable response to steroidal and bronchodilator therapies in patients with stable COPD.

Impact and associations of eosinophilic inflammation in COPD: analysis of the AERIS cohort

Eosinophilic inflammation in chronic obstructive pulmonary disease (COPD) predicts response to treatment, especially corticosteroids. We studied the nature of eosinophilic inflammation in COPD prospectively to examine the stability of this phenotype and its dynamics across exacerbations, and its associations with clinical phenotype, exacerbations and infection.127 patients aged 40-85 years with moderate to very severe COPD underwent repeated blood and sputum sampling at stable visits and within 72 h of exacerbation for 1 year.Blood eosinophils ≥2% was prevalent at baseline, and predicted both predominantly raised stable-state eosinophils across the year (area under the curve 0.841, 95% CI 0.755-0.928) and increased risk of eosinophilic inflammation at exacerbation (OR 9.16; p<0.001). Eosinophils ≥2% at exacerbation and eosinophil predominance at stable visits were associated with a lower risk of bacterial presence at exacerbation (OR 0.49; p=0.049 and OR 0.25; p=0.065, respectively). Bacterial infection at exacerbation was highly seasonal (winter versus summer OR 4.74; p=0.011) in predominantly eosinophilic patients.Eosinophilic inflammation is a common and stable phenotype in COPD. Blood eosinophil counts in the stable state can predict the nature of inflammation at future exacerbations, which when combined with an understanding of seasonal variation provides the basis for the development of new treatment paradigms for this important condition.

Blood Eosinophils and Response to Maintenance Chronic Obstructive Pulmonary Disease Treatment. Data from the FLAME Trial

RATIONALE

Post hoc analyses suggest that blood eosinophils have potential as a predictive biomarker of inhaled corticosteroid efficacy in the management of chronic obstructive pulmonary disease (COPD).

OBJECTIVES

We prospectively investigated the value of blood eosinophils as a predictor of responsiveness to an inhaled corticosteroid/long-acting β₂-agonist combination versus a long-acting β₂-agonist/long-acting muscarinic antagonist combination for exacerbation prevention.

METHODS

We conducted prespecified analyses of data from the FLAME (Effect of Indacaterol Glycopyronium vs Fluticasone Salmeterol on COPD Exacerbations) study, which compared once-daily long-acting β₂-agonist/long-acting muscarinic antagonist indacaterol/glycopyrronium 110/50 μg with twice-daily long-acting β₂-agonist/inhaled corticosteroid salmeterol/fluticasone combination 50/500 μg in patients with one or more exacerbations in the preceding year. Subsequent post hoc analyses were conducted to address further cutoffs and endpoints.

MEASUREMENTS AND MAIN RESULTS

We compared treatment efficacy according to blood eosinophil percentage (<2% and ≥2%, <3% and ≥3%, and <5% and ≥5%) and absolute blood eosinophil count (<150 cells/μl, 150 to <300 cells/μl, and ≥300 cells/μl). Indacaterol/glycopyrronium was significantly superior to salmeterol/fluticasone for the prevention of exacerbations (all severities, or moderate or severe) in the <2%, ≥2%, <3%, <5%, and <150 cells/μl subgroups, and at no cutoff was salmeterol/fluticasone superior to indacaterol/glycopyrronium. Furthermore, the rate of moderate or severe exacerbations did not increase with increasing blood eosinophils. The incidence of pneumonia was higher in patients receiving salmeterol/fluticasone than indacaterol/glycopyrronium in both the <2% and ≥2% subgroups.

CONCLUSIONS

Our prospective analyses indicate that indacaterol/glycopyrronium provides superior or similar benefits over salmeterol/fluticasone regardless of blood eosinophil levels in patients with COPD. Clinical trial registered with www.clinicaltrials.gov (NCT01782326).

Eosinophilic and Neutrophilic Airway Inflammation in the Phenotyping of Mild-to-Moderate Asthma and Chronic Obstructive Pulmonary Disease

Asthma and chronic obstructive pulmonary disease (COPD) are heterogeneous diseases with different inflammatory phenotypes. Various inflammatory mediators play a role in these diseases. The aim of this study was to analyze the neutrophilic and eosinophilic airway and systemic inflammation as the phenotypic characterization of patients with asthma and COPD. Twenty-four patients with asthma and 33 patients with COPD were enrolled in the study. All the patients were in mild-to-moderate stage of disease, and none of them were treated with inhaled corticosteroids. Concentrations of IL-6, neutrophil elastase (NE), matrix metalloproteinase 9 (MMP-9), eosinophil cationic protein (ECP), and IL-33 and IL-17 in serum and induced sputum (IS) were measured by enzyme-linked immunosorbent assay (ELISA). The cellular composition of blood and IS was evaluated. Hierarchical clustering of patients was performed for the combination of selected clinical features and mediators. Asthma and COPD can be differentiated based on eosinophilic/neutrophilic systemic or airway inflammation with unsatisfactory efficiency. Hierarchical clustering of patients based on blood eosinophil percentage and clinical data revealed two asthma clusters differing in the number of positive skin prick tests and one COPD cluster with two subclusters characterized by low and high blood eosinophil concentrations. Clustering of patients according to IS measurements and clinical data showed two main clusters: pure asthma characterized by high eosinophil/atopy status and mixed asthma and COPD cluster with low eosinophil/atopy status. The neutrophilic phenotype of COPD was associated with more severe airway obstruction and hyperinflation.

The Time Course of Pulmonary Function Tests in COPD Patients with Different Levels of Blood Eosinophils

Only very few studies have investigated the influence of eosinophils on the functional progression of COPD. We aimed at retrospectively analyzing the trend of pulmonary function tests over time in patients with COPD according to two baseline blood eosinophil cell count strata (<2% [EOS-] and ≥2% [EOS+]). We used the last 9-year data present in the database of our outpatient clinic and selected only those who had two blood counts that would guarantee the stability of the value of eosinophils and serial spirometry for 4 consecutive years. The analysis of the time course of the spirometric variables analysed showed differences in FEV1 and FVC decline between the subjects of the EOS- group and those of the EOS+ group. The integrated evaluation of our results suggests that the different level of blood eosinophils in the two groups may have influenced independently the time course of the pulmonary function tests and identify two subgroups of subjects with specific disease characteristics: the hyperinflator and the rapid decliner, respectively.

Comparison of the clinical characteristics and treatment outcomes of patients requiring hospital admission to treat eosinophilic and neutrophilic exacerbations of COPD

PURPOSE

We compared the clinical characteristics and treatment outcomes of patients with eosinophilic and neutrophilic COPD exacerbations requiring hospital admission.

PATIENTS AND METHODS

This was a retrospective multicenter study performed between January 2010 and December 2014. In all, 1,688 COPD patients admitted via the outpatient clinics or emergency departments of six university hospitals were enrolled. The patients were grouped by complete blood counts: eosinophilic group, >2% peripheral blood eosinophils, and neutrophilic group, >65% peripheral blood neutrophils or >11,000 leukocytes/mL. The patients with radiographic evidence of pneumonia at the time of admission, those with lung cancer, those admitted for treatment of other medical problems, and those who chronically used steroids were excluded.

RESULTS

A total of 605 patients hospitalized with COPD exacerbations (177 eosinophilic and 380 neutrophilic) were included. Pulmonary functions, including the forced expiratory volume in 1 second and forced vital capacity, were better in patients with eosinophilic exacerbations. Treatment outcomes, including the rate of admission to the intensive care unit and mortality, were poorer in patients with neutrophilic exacerbations (4.5% vs 12.4%, P=0.004; 1.1% vs 4.5%, P=0.043, respectively). Congestive heart failure (odds ratio [OR] =3.40, 95% confidence interval [CI]: 1.28-9.01) and neutrophilic exacerbation (OR = 2.81, 95% CI: 1.21-6.52) were independent risk factors for intensive care unit admission.

CONCLUSION

COPD patients with neutrophilic exacerbations experienced worse clinical outcomes than did those with eosinophilic exacerbations. The peripheral blood eosinophil count may be a useful predictor of clinical progress during hospitalization of COPD patients with acute exacerbations.

Effectiveness using higher inhaled corticosteroid dosage in patients with COPD by different blood eosinophilic counts

BACKGROUND

Blood eosinophil counts have been documented as a good biomarker for patients with chronic obstructive pulmonary disease (COPD) using inhaled corticosteroid (ICS) therapy. However, the effectiveness and safety of prescribing high or medium dose of ICS for patients with different eosinophil counts are unknown.

METHODS

A post hoc analysis of a previous prospective randomized study was performed for COPD patients using higher dose (HD: Fluticasone 1,000 μg/day) or medium dose (MD: Fluticasone 500 μg/day) of ICS combined with Salmeterol (100 μg/day). Patients were classified into two groups: those with high eosinophil counts (HE ≥3%) and those with low eosinophil counts (LE <3%). Lung function was evaluated with forced expiratory volume in 1 second, forced vital capacity, and COPD assessment test. Frequencies of acute exacerbation and pneumonia were also measured.

RESULTS

Two hundred and forty-eight patients were studied and classified into higher eosinophil (HE) (n=85, 34.3%) and lower eosinophil (LE) groups (n=163, 65.7%). The levels of forced expiratory volume in 1 second were significantly increased in patients of HE group treated with HD therapy, compared with the other groups (HE/HD: 125.9±27.2 mL vs HE/MD: 94.3±23.7 mL, vs LE/HD: 70.4±20.5 mL, vs LE/MD: 49.8±16.7 mL; P<0.05) at the end of the study. Quality of life (COPD assessment test) markedly improved in HE/HD group than in MD/LE group (HE/HD: 9±5 vs LE/MD: 16±7, P=0.02). The frequency of acute exacerbation was more decreased in HE/HD group patients, compared with that in LE/MD group (HE/HD: 13.5% vs LE/MD: 28.7%, P<0.01). Pneumonia incidence was similar in the treatment groups (HE/HD: 3.2%, HE/MD: 2.6%, LE/HD: 3.5%, LE/MD 2.8%; P=0.38).

CONCLUSION

The study results support using blood eosinophil counts as a biomarker of ICS response and show the benefits of greater improvement of lung function, quality of life, and decreased exacerbation frequency in COPD patients with blood eosinophil counts higher than 3%, especially treated with higher dose of ICS.