Inflammatory and Comorbid Features of Patients with Severe Asthma and Frequent Exacerbations

An expert review on breaking barriers in severe asthma in Brazil: Time to act

Currently, Brazil lacks a national asthma management program and is burdened with nearly 200,000 hospitalizations due to the disease per year and approximately 5 deaths per day. The purpose of this article was to analyze the current issues surrounding severe asthma in Brazil, as the status of diagnosis and treatment is largely unknown, and to provide feasible recommendations to elicit imminent action. A panel of Brazilian medical experts in the field of severe asthma was provided with a series of relevant questions to address prior to a multi-day conference. Within this conference, each narrative was discussed and edited by the entire group. Through numerous rounds of discussion consensus was achieved. In order to overcome barriers to adequate asthma treatment, this panel recommends specific initiatives that can be implemented in the short-term to decrease the burden of severe asthma in Brazil. With increasing healthcare costs and limited resources globally, there is an opportunity to implement these recommendations in other countries in order to achieve adequate asthma care. Severe asthma is a heterogeneous and complex disease with various phenotypes that requires strict attention for diagnosis and management. Although this disease affects only a small proportion of the population with asthma, it poses a great burden to healthcare systems. Thus, barriers to diagnosis, treatment, and management should be overcome as quickly and efficiently as possible.

Risk Factors Predicting Severe Asthma Exacerbations in Adult Asthmatics: A Real-World Clinical Evidence

PURPOSE

Minimizing the future risk of asthma exacerbation (AE) is one of the main goals of asthma management. We investigated prognostic factors for risk of severe AE (SAE) in a real-world clinical setting.

METHODS

This is an observational study evaluating subjects who were diagnosed with asthma and treated with anti-asthmatic medications from January 1995 to June 2018. Risk factors for SAE were analyzed in 2 treatment periods (during the initial 2 years and the following 3-10 years of treatment) using the big data of electronic medical records.

RESULTS

In this study, 5,058 adult asthmatics were enrolled; 1,335 (28.64%) experienced ≥ 1 SAE during the initial 2 years of treatment. Female sex, higher peripheral eosinophil/basophil counts, and lower levels of forced expiratory volume in 1 second (FEV1; %) were factors predicting the risk of SAEs (P < 0.001 for all). Higher serum total immunoglobulin E levels increased the risk of SAEs among the patients having ≤ 2 SAEs (P = 0.025). Patients with more frequent SAEs during the initial 2 years of treatment had significantly higher risks of SAEs during the following years of treatment (P < 0.001, for all) (patients with ≥ 4 SAEs, odds ratio [OR], 29.147; those with 3 SAEs, OR, 14.819; those with 2 SAEs, OR, 9.867; those with 1 SAE, OR, 5.116), had higher maintenance doses of systemic steroids, and showed more gradual decline in FEV1 (%) and FEV1/forced vital capacity levels maintained during the following years of treatment (P < 0.001 for all).

CONCLUSIONS

Asthmatics having risk factors for SAEs (female sex, higher peripheral eosinophil/basophil counts, and lower FEV1) should be strictly monitored to prevent future risk and improve clinical outcomes.

Clinical and Inflammatory Features of Exacerbation-Prone Asthma: A Cross-Sectional Study Using Multidimensional Assessment

BACKGROUND

Reducing asthma exacerbations is a major target of current clinical guidelines, but identifying features of exacerbation-prone asthma (EPA) using multidimensional assessment (MDA) is lacking.

OBJECTIVE

To systemically explore the clinical and inflammatory features of adults with EPA in a Chinese population.

METHODS

We designed a cross-sectional study using the Severe Asthma Web-based Database from the Australasian Severe Asthma Network (ASAN). Eligible Chinese adults with asthma (n = 546) were assessed using MDA. We stratified patients based on exacerbation frequency: none, few (1 or 2), and exacerbation prone (≥3). Univariate and multivariable negative binomial regression analyses were performed to investigate features associated with the frequency of exacerbations.

RESULTS

Of 546 participants, 61.9% had no exacerbations (n = 338), 29.6% had few exacerbations (n = 162), and 8.4% were exacerbation prone (n = 46) within the preceding year. EPA patients were characterized by elevated blood and sputum eosinophils but less atopy, with more controller therapies but worse asthma control and quality of life (all p < 0.05). In multivariable models, blood and sputum eosinophils (adjusted rate ratio = 2.23, 95% confidence interval = [1.26, 3.84] and 1.67 [1.27, 2.21], respectively), FEV1 (0.90 [0.84, 0.96]), bronchodilator responsiveness (1.16 [1.05, 1.27]), COPD (2.22 [1.41, 3.51]), bronchiectasis (2.87 [1.69, 4.89]), anxiety (2.56 [1.10, 5.95]), and depression (1.94 [1.20, 3.13]) were found. Further, upper respiratory tract infection (1.83 [1.32, 2.54]) and food allergy (1.67 [1.23, 2.25]) were at high risk of asthma symptom triggers.

CONCLUSION

EPA is a clinically recognizable phenotype associated with several recognizable traits that could be addressed by targeted treatment.

Lipid metabolism and identification of biomarkers in asthma by lipidomic analysis

BACKGROUND

Lipids participate in many important biological functions through energy storage, material transport, signal transduction, and molecular recognition processes. Studies have reported that asthmatic patients have abnormal lipid metabolism. However, there are limited studies on the characterization of lipid metabolism in asthmatic patients by lipidomics.

METHODS

We characterized the plasma lipid profile of 28 healthy controls and 33 outpatients with asthma (18 mild, 15 moderate) by liquid chromatography mass spectrometry/mass spectrometry-based lipidomics.

RESULTS

We determined 1338 individual lipid species in the plasma. Significant changes were identified in ten lipid species in asthmatic patients than in healthy controls (all P < 0.05). Phosphatidylethanolamine (PE) (18:1p/22:6), PE (20:0/18:1), PE (38:1), sphingomyelin (SM) (d18:1/18:1), and triglyceride (TG) (16:0/16:0/18:1) positively correlated with the severity of asthma (all P < 0.05). Phosphatidylinositol (PI) (16:0/20:4), TG (17:0/18:1/18:1), phosphatidylglycerol (PG) (44:0), ceramide (Cer) (d16:0/27:2), and lysophosphatidylcholine (LPC) (22:4) negatively correlated with the severity of asthma (all P < 0.05). Correlation analysis showed a significant correlation between all ten lipid species (all P < 0.05). From the area under the curve of the receiver operating characteristic curve analysis, PE (38:1) was the major lipid metabolite that distinguished asthmatic patients from healthy controls, and may be considered a potential lipid biomarker. PE (20:0/18:1) and TG (16:0/16:0/18:1) might be related to IgE levels in asthmatic patients.

CONCLUSIONS

Our results indicated the presence of abnormal lipid metabolism, which correlated with the severity and IgE levels in asthmatic patients.

The impact of clinical and psychological factors on asthma control: the experience of a single asthma center in Poland

OBJECTIVE

The asthma control test (ACT) is commonly used to identify patients with uncontrolled asthma. The goal of this study was to determine whether clinical parameters such as asthma history and medications, exacerbation rate, comorbidities, lung function, and socioeconomic status are risk factors for uncontrolled asthma assessed with the ACT, and to evaluate the psychological status of controlled and uncontrolled asthmatics.

METHODS

Adult asthmatics (n = 104) were recruited from a single asthma center, Poland. Asthma control was assessed with the ACT, using <20 as the cutoff point for uncontrolled asthma. Data on clinical factors were collected and spirometry was performed. Patients completed the Asthma Quality of Life Questionnaire, General Health Questionnaire, Acceptance of Illness Scale, Life Orientation Test-Revised, and Eysenck's Personality Inventory.

RESULTS

Asthma was uncontrolled in 42.3% of patients. Asthma exacerbations in the preceding 12 months and high inhaled corticosteroid (ICS) doses were identified as independent risk factors for uncontrolled asthma. Uncontrolled asthmatics had a significantly worse psychological status than controlled asthmatics. The groups did not differ in terms of personality traits, but in the controlled asthma group numerous significant correlations between psychological factors and personality traits were observed. In the uncontrolled asthma group, however, the occurrence of correlations between personality traits and other psychological variables was rarer.

CONCLUSIONS

The study identified independent risk factors for uncontrolled asthma, namely, exacerbations in the recent 12 months and treatment with high-dose ICS. Uncontrolled asthmatics have a significantly worse psychological status than controlled asthmatics, irrespective of personality traits.

Blood Eosinophil Count and Hospital Readmission in Patients with Acute Exacerbation of Chronic Obstructive Pulmonary Disease

Purpose

This retrospective, observational cohort study investigated the association of blood eosinophil counts within 1 week of hospitalization for acute exacerbation of COPD (AECOPD) with subsequent risk of all-cause and COPD-related readmission from a large integrated health system.

Patients and Methods

Electronic medical records were extracted for index hospitalization for AECOPD at all Intermountain Healthcare hospitals. The primary outcome was the relationship of blood eosinophil count to 30-day all-cause readmission; secondary outcomes were 60-day, 90-day, and 12-month all-cause readmission, COPD-related readmission, and empiric derivation of the eosinophil count with the highest area under the curve (AUC) for predicting 30-day all-cause readmission.

Results

Of 2445 included patients, 1935 (79%) had a blood eosinophil count <300 cells/µL and 510 (21%) had a count ≥300 cells/µL. Using a 300-cells/μL threshold, there was no significant difference between high and low eosinophil groups in 30-day (odds ratio [OR]=1.05, 95% confidence interval [CI]=0.75–1.47) or 60-day (OR=1.15, 95% CI=0.88–1.51) all-cause readmissions. However, patients with greater (versus lesser) eosinophil counts had increased 90-day and 12-month all-cause readmissions (OR=1.35, 95% CI=1.06–1.72, and OR=1.32, 95% CI=1.07–1.62). COPD-related readmission rates were significantly greater for patients with greater (versus lesser) eosinophil counts at 30, 60, and 90 days and 12 months (OR range=1.52–1.97). A total of 70 cells/µL had the most discriminatory power to predict 30-day all-cause readmission (highest AUC).

Conclusion

Eosinophil counts in patients with COPD were not associated with a difference in 30-day all-cause readmissions. However, greater eosinophil counts were associated with increased risk of all-cause readmission at 90 days and 12 months and COPD-related readmission at 30, 60, and 90 days and 12 months. Patients with eosinophils <70 cells/μL had the lowest risk for 30-day all-cause readmission. Blood eosinophils in patients hospitalized with AECOPD may be a useful biomarker for the risk of hospital readmission.

The Clinical Course of Asthma After Withdrawal of Inhaled Corticosteroids

BACKGROUND

Maintenance of inhaled corticosteroids (ICSs) is recommended in adults with asthma. However, adherence rates in patients with mild asthma and side effects of long-term ICS use can lead to withdrawal.

OBJECTIVE

To analyze the real-world outcomes of ICS withdrawal by analyzing data from the Korean National Health Insurance database.

METHODS

Based on claims data from the National Health Insurance of Korea between 2011 and 2014, we identified patients diagnosed with asthma without chronic obstructive pulmonary disease or long-term systemic steroid use who had an ICS medication possession rate of more than 50% in a year. We compared patients who received ICS consistently (maintenance group) with patients who had no ICS prescription for more than 6 months (withdrawal group). We evaluated exacerbation leading to prescription of systemic steroid and emergency department visit or hospitalization.

RESULTS

Excluding patients with chronic obstructive pulmonary disease and long-term systemic steroid users, we identified 145,511 patients for the asthma cohort (mean age, 60.0 years; ever-smoker, 63.5%): 132,175 maintained ICS and 13,336 withdrew ICS for more than 6 months. Only 71 patients (0.5%) experienced exacerbation leading to an emergency department visit or hospitalization in the withdrawal group. ICS was restarted within 1 year for 33.6% of the withdrawal group, and 90% of these patients restarted ICS within 158 days.

CONCLUSIONS

This nationwide study of patients with asthma, characterized by a high proportion of elderly and smokers, showed that ICS withdrawal in about 10% of patients appeared to confer relatively minimal harm and exacerbation leading to hospitalization was not common. Further prospective studies are warranted to carefully explore the safety of ICS withdrawal in younger, nonsmoking, and well-controlled patients with asthma.

Evidence for Exacerbation-Prone Asthma and Predictive Biomarkers of Exacerbation Frequency

Rationale: Cross-sectional studies suggest an exacerbation-prone asthma (EPA) phenotype and the utility of blood eosinophils and plasma IL-6 as predictive biomarkers.Objectives: To prospectively test for EPA phenotype and utility of baseline blood measures of eosinophils and IL-6 as predictive biomarkers.Methods: Three-year asthma exacerbation data were analyzed in 406 adults in the Severe Asthma Research Program-3. Transition models were used to assess uninformed and informed probabilities of exacerbation in year 3. Binomial regression models were used to assess eosinophils and IL-6 as predictive biomarkers.Measurements and Main Results: Eighty-three participants (21%) had ≥1 exacerbation in each year (EPA) and 168 participants (41%) had no exacerbation in any year (exacerbation-resistant asthma). The uninformed probability of an exacerbation in Year 3 was 40%, but the informed probability increased to 63% with an exacerbation in Year 2 and 82% with an exacerbation in Years 1 and 2. The probability of a Year 3 exacerbation with no Year 1 or 2 exacerbations was 13%. Compared with exacerbation-resistant asthma, EPA was characterized by lower FEV₁ and a higher prevalence of obesity, hypertension, and diabetes. High-plasma IL-6 occurred in EPA, and the incident rate ratio for exacerbation increased 10% for each 1-pg/μl increase in baseline IL-6 level. Although high blood eosinophils did not occur in EPA, the incident rate ratio for exacerbations increased 9% for each 100-cell/μl increase in baseline eosinophil number.Conclusions: Longitudinal analysis confirms an EPA phenotype characterized by features of metabolic dysfunction. Blood measures of IL-6, but not eosinophils, were significantly associated with EPA, and IL-6 and eosinophils predicted exacerbations in the sample as a whole.

Association of obesity with severity outcomes in hospitalized pediatric asthma exacerbations

INTRODUCTION

While there seems to be an association between obesity and asthma, the exact nature of the relationship remains unknown. It is unclear if there is increased severity of exacerbation for those that require hospitalization. We examine the association between obesity and severity outcomes such as hospital length of stay, intensive care admissions, and need for continuous albuterol or magnesium administration.

METHODS

Patients 4 to 17 years old admitted between 1/1/2012-1/1/2016 with asthma identified by discharge codes were reviewed. Obesity was defined as BMI ≥95%. Clinical data such as age, gender, family history of asthma, use of controller medication along with outcome data such as length of stay, ICU admission, use of continuous albuterol, and use of magnesium were collected. Binary outcomes were analyzed with multivariate logistic regression while length of stay was analyzed with negative binomial regression.

RESULTS

Overall, 995 patients met inclusion criteria. The median age was 7 years old with 170 (17%) patients categorized as obese. We find no difference in length of stay (IRR 0.99 [0.91, 1.09], p = 0.9), PICU admission (OR 0.72 [0.43, 1.21], p = 0.22), or magnesium administration (OR 1.34 [0.95, 1.88], p = 0.09) between obese and non-obese patients. There were increased odds of continuous albuterol use (OR 1.47 [1.02, 2.11]) for obese patients.

CONCLUSION

We find no association between obesity and outcomes of length of stay, ICU admission, or magnesium administration. While growing evidence links obesity with asthma, our study suggests it may not be associated with the severity of exacerbation.

An update on the role of chronic rhinosinusitis with nasal polyps as a co-morbidity in severe asthma

INTRODUCTION

Chronic rhinosinusitis and asthma are heterogeneous diseases with complex pathogenesis. The presence of chronic rhinosinusitis with nasal polyps has been associated with increased asthma exacerbation frequency and may represent a predictor of future exacerbations in severe asthma.

AREAS COVERED

This review provides the clinician with an overview of the prevalence and clinical impact of the chronic rhinosinusitis with nasal polyps in severe asthma and summarizes recommended therapeutic approaches, including innovative biologic therapies. To select relevant literature for inclusion in this review, we conducted a literature search using the PubMed and ClinicalTrials.gov databases, using terms 'chronic rhinosinusitis with nasal polyps' AND 'asthma' OR 'severe asthma.' The literature review was performed for publication years 2010-2020, restricting the articles to humans and English language publications.

EXPERT OPINION

Biological therapies have opened new perspectives in the treatment of upper and lower airway allergic diseases. Care pathways in severe asthma are almost consolidated, while they still rely on phenotypic rather than endotypic features in chronic rhinosinusitis with nasal polyps. Unveiling the correlation between clinical phenotypes and molecular endotypes will allow better stratification of patients with chronic rhinosinusitis with nasal polyps to identify candidates who benefit most from biological therapy.

Towards a personalised treatment approach for asthma attacks

Asthma attacks (exacerbations) are common, accounting for over 90 000 UK hospital admissions per annum. They kill nearly 1500 people per year in the UK, have significant associated direct and indirect costs and lead to accelerated and permanent loss of lung function. The recognition of asthma as a heterogeneous condition with multiple phenotypes has revolutionised the approach to the long-term management of the condition, with greater emphasis on personalised treatment and the introduction of the treatable traits concept. In contrast asthma attacks are poorly defined and understood and our treatment approach consists of bronchodilators and systemic corticosteroids. This review aims to explore the current limitations in the description, assessment and management of asthma attacks. We will outline the risk factors for attacks, strategies to modify this risk and describe the recognised characteristics of attacks as a first step towards the development of an approach for phenotyping and personalising the treatment of these critically important events. By doing this, we hope to gradually improve asthma attack treatment and reduce the adverse effects associated with recurrent courses of corticosteroids.

Novel Therapies for Pneumonia-Associated Severe Asthma Phenotypes

Distinct asthma phenotypes are emerging from well-defined cohort studies and appear to be associated with a history of pneumonia. Asthmatics are more susceptible to infections caused by Streptococcus pneumoniae; however, the mechanisms that underlie defective immunity to this pathogen are still being elucidated. Here, we discuss how alternatively activated macrophages (AAMs) in asthmatics are defective in bacterial phagocytosis and how respiratory viruses disrupt essential host immunity to cause bacterial dispersion deeper into the lungs. We also describe how respiratory pathogens instigate neutrophilic inflammation and amplify type-2 inflammation in asthmatics. Finally, we propose novel dual-acting strategies including granulocyte-colony-stimulating factor receptor (G-CSFR) antagonism and specialised pro-resolving mediators (SPMs) to suppress type-2 and neutrophilic inflammation without compromising pathogen clearance.

Biologics for Severe Asthma: Treatment-Specific Effects Are Important in Choosing a Specific Agent

Patients with uncontrolled severe persistent asthma have greater morbidity, greater use of health care resources, and more impairment in health-related quality of life when compared with their peers with well-controlled disease. Fortunately, since the introduction of biological therapeutics, patients with severe eosinophilic asthma now have beneficial treatment options that they did not have just a few years ago. In addition to anti-IgE therapy for allergic asthma, 3 new biological therapeutics targeting IL-5 and 1 targeting IL-4 and IL-13 signaling have recently been approved by the Food and Drug Administration for the treatment of severe eosinophilic asthma, and approval of more biological therapeutics is on the horizon. These medications decrease the frequency of asthma exacerbations, improve lung function, reduce corticosteroid usage, and improve health-related quality of life. This article reviews the mechanisms of action, specific indications, benefits, and side effects of each of the approved biological therapies for asthma. Furthermore, this article reviews how a clinician could use specific patient characteristics to decide which biologic treatment may be optimal for a given patient.

Multidimensional Assessment of Asthma Identifies Clinically Relevant Phenotype Overlap: A Cross-Sectional Study

BACKGROUND

Asthma is a heterogeneous disease with multiple phenotypes; however, the relevance of phenotype overlap remains largely unexplored.

OBJECTIVE

To examine the relationship between phenotype overlap and clinical and inflammatory profiles of asthma.

METHODS

In this cross-sectional study, adult participants with stable asthma (n = 522) underwent multidimensional assessments. The 10 most common phenotypes of asthma were defined and then classified into those commonly associated with Type (T) 2 or non-T2 inflammation. Furthermore, phenotype overlap scores (POS), representing the cumulative concomitant phenotypes, were used to analyze its association with clinical and inflammatory asthmatic profiles.

RESULTS

Among the 522 participants, 73.4% (n = 383) had phenotype overlap, and mixed T2 and non-T2 inflammation coexisted in 47.5% (n = 248). T2 POS was positively associated with eosinophils, IgE, and fractional exhaled nitric oxide (FeNO), and negatively with Asthma Quality of Life Questionnaire (AQLQ), sputum neutrophils, IL-17A, IL-8, and TNF-α. Non-T2 POS was positively associated with Asthma Control Questionnaire, neutrophils and sputum IL-8, and negatively with AQLQ, forced expiratory volume in 1 s, blood eosinophils, IgE, and FeNO (all P < .05). Patients with phenotypes that are associated with mixed T2 and non-T2 inflammation had elevated T2 inflammation biomarkers but worse asthma control. Both T2 (adjusted β = -0.191, P = .035) and non-T2 (adjusted β = 0.310, P < .001) POS were significantly associated with severe exacerbations.

CONCLUSIONS

Phenotype overlap is extremely common in asthmatic patients and significantly associated with clinical and inflammatory profiles. Patients with phenotypes associated with mixed T2 and non-T2 inflammation might be unresponsive to medications owing to increased non-T2 inflammation. Multidimensional asthma assessment identifies clinically relevant phenotype overlap.

Genetic analyses identify GSDMB associated with asthma severity, exacerbations, and antiviral pathways

BACKGROUND

The Chr17q12-21.2 region is the strongest and most consistently associated region with asthma susceptibility. The functional genes or single nucleotide polymorphisms (SNPs) are not obvious due to linkage disequilibrium.

OBJECTIVES

We sought to comprehensively investigate whole-genome sequence and RNA sequence from human bronchial epithelial cells to dissect functional genes/SNPs for asthma severity in the Severe Asthma Research Program.

METHODS

Expression quantitative trait loci analysis (n = 114), correlation analysis (n = 156) of gene expression and asthma phenotypes, and pathway analysis were performed in bronchial epithelial cells and replicated. Genetic association for asthma severity (426 severe vs 531 nonsevere asthma) and longitudinal asthma exacerbations (n = 273) was performed.

RESULTS

Multiple SNPs in gasdermin B (GSDMB) associated with asthma severity (odds ratio, >1.25) and longitudinal asthma exacerbations (P < .05). Expression quantitative trait loci analyses identified multiple SNPs associated with expression levels of post-GPI attachment to proteins 3, GSDMB, or gasdermin A (3.1 × 10^-9 <P < 1.8 × 10^-4). Higher expression levels of GSDMB correlated with asthma and greater number of exacerbations (P < .05). Expression levels of GSDMB correlated with genes involved in IFN signaling, MHC class I antigen presentation, and immune system pathways (false-discovery rate-adjusted P < .05). rs1031458 and rs3902920 in GSDMB colocalized with IFN regulatory factor binding sites and associated with GSDMB expression, asthma severity, and asthma exacerbations (P < .05).

CONCLUSIONS

By using a unique set of gene expression data from lung cells obtained using bronchoscopy from comprehensively characterized subjects with asthma, we show that SNPs in GSDMB associated with asthma severity, exacerbations, and GSDMB expression levels. Furthermore, its expression levels correlated with asthma exacerbations and antiviral pathways. Thus, GSDMB is a functional gene for both asthma susceptibility and severity.

Plasma P-Selectin Is Inversely Associated with Lung Function and Corticosteroid Responsiveness in Asthma

BACKGROUND

Severe asthma has multiple phenotypes for which biomarkers are still being defined. Plasma P-selectin reports endothelial and/or platelet activation.

OBJECTIVE

To determine if P-selectin is associated with features of asthma in a longitudinal study.

METHODS

Plasmas from 70 adult patients enrolled in the Severe Asthma Research Program (SARP) III at the University of Wisconsin-Madison were analyzed for concentration of P-selectin at several points over the course of 3 years, namely, at baseline (BPS), after intramuscular triamcinolone acetonide (TA) injection, and at 36 months after baseline. Thirty-four participants also came in during acute exacerbation and 6 weeks after exacerbation.

RESULTS

BPS correlated inversely with forced expiratory volume in 1 s (FEV1) and with residual volume/total lung capacity, an indicator of air trapping. BPS was inversely associated with FEV1 change after TA, by regression analysis. FEV1 did not change significantly after TA if BPS was above the median, whereas patients with BPS below the median had significantly increased FEV1 after TA. BPS was higher in and predicted assignment to SARP phenotype cluster 5 ("severe fixed-airflow asthma"). P-selectin was modestly but significantly increased at exacerbation but returned to baseline within 3 years.

CONCLUSIONS

High BPS is associated with airway obstruction, air trapping, the "severe fixed-airflow" cluster, and lack of FEV1 improvement in response to TA injection. P-selectin concentration, which is a stable trait with only modest elevation during exacerbation, may be a useful biomarker for a severe asthma pheno- or endotype characterized by low pulmonary function and lack of corticosteroid responsiveness.

Preclinical characterization of CPL302-253, a selective inhibitor of PI3Kδ, as the candidate for the inhalatory treatment and prevention of Asthma

Asthma is a common chronic inflammatory disease. Although effective asthma therapies are available, part of asthmatic population do not respond to these treatment options. In this work we present the result of development of CPL302-253 molecule, a selective PI3Kδ inhibitor. This molecule is intended to be a preclinical candidate for dry powder inhalation in asthma treatment. Studies we performed showed that this molecule is safe and effective PI3Kδ inhibitor that can impact many immune functions. We developed a short, 15-day HDM induced asthma mouse model, in which we showed that CPL302-253 is able to block inflammatory processes leading to asthma development in vivo.

Clinical Characterization of the Frequent Exacerbator Phenotype in Asthma

Background: Asthma exacerbation is episodic worsening of respiratory symptoms in conjunction with the deterioration of lung function, which may occur independently from the asthma severity hampering asthmatics’ quality of life. This study aimed to characterize the patient phenotype more prone to asthma exacerbation (oral corticosteroid burst ≥2 per year) to allow the proper identification of such patients. Methods: This real-life, observational, cross-sectional study evaluated 464 asthmatic patients stratified according to the asthma exacerbations experienced in the previous year. Clinical, functional, and blood parameters were retrieved from chart data and were representative of patients in stable conditions. Results: The frequent asthma exacerbator was more commonly female, suffered from chronic rhinosinusitis with nasal polyposis, had reduced lung function and peripheral oxygen saturation, and had increased daily activity limitations. These patients often had severe asthma and more frequently needed hospitalization in their lives. Furthermore, the frequent asthma exacerbator had higher concentrations of serum immunoglobulin E (IgE) and exhaled nitric oxide with cut-off risk values of 107.5 kU/L (OR = 4.1) and 43.35 ppb (OR = 3.8), respectively. Conclusions: This study illustrates the clinical features of the frequent asthma exacerbator phenotype. Nevertheless, serum IgE and exhaled nitric oxide could allow the identification of this phenotype and the establishment of an appropriate therapeutic approach.

Are We Meeting the Promise of Endotypes and Precision Medicine in Asthma?

While the term asthma has long been known to describe heterogeneous groupings of patients, only recently have data evolved which enable a molecular understanding of the clinical differences. The evolution of transcriptomics (and other 'omics platforms) and improved statistical analyses in combination with large clinical cohorts opened the door for molecular characterization of pathobiologic processes associated with a range of asthma patients. When linked with data from animal models and clinical trials of targeted biologic therapies, emerging distinctions arose between patients with and without elevations in type 2 immune and inflammatory pathways, leading to the confirmation of a broad categorization of type 2-Hi asthma. Differences in the ratios, sources, and location of type 2 cytokines and their relation to additional immune pathway activation appear to distinguish several different (sub)molecular phenotypes, and perhaps endotypes of type 2-Hi asthma, which respond differently to broad and targeted anti-inflammatory therapies. Asthma in the absence of type 2 inflammation is much less well defined, without clear biomarkers, but is generally linked with poor responses to corticosteroids. Integration of "big data" from large cohorts, over time, using machine learning approaches, combined with validation and iterative learning in animal (and human) model systems is needed to identify the biomarkers and tightly defined molecular phenotypes/endotypes required to fulfill the promise of precision medicine.

[Effects of artesunate on eosinophil apoptosis and expressions of Fas and Bcl-2 proteins in asthmatic mice]

OBJECTIVE

To observe the effects of artesunate on eosinophil (EOS) apoptosis and Fas and Bcl-2 protein expressions in asthmatic mice.

METHODS

Thirty female BALB/c mice aged 6-8 weeks were randomly divided into control group, asthma group and artesunate group. Except for those in the control group, all the mice were sensitized with aerosolized ovalbumin to establish mouse models of asthma. In artesunate group, the rats were intraperitoneally injected with artesunate 1 h before ovalbumin inhalation from the 21st day of modeling. The lung tissues were harvested for staining 24 h after the last challenge. Flow cytometry was used to analyze the percentage and apoptosis rate of EOS in the alveolar lavage fluid (BALF). The apoptosis of EOS in the lung tissue was detected with TUNEL method, and Fas and Bcl-2 protein expressions were detected using immunohistochemistry.

RESULTS

Compared with those in asthma group, the artesunate-treated mice had significantly decreased percentage of EOS in the BALF (P < 0.05) with increased apoptosis rate of EOS in the BALF and the lung tissue (P < 0.05). The Fas-positive area and IOD of Fas protein in the lung tissue increased (P < 0.05) while the Bcl-2-positive area and IOD of Bcl-2 protein decreased significantly in artesunate-treated mice as compared with the asthmatic mice (P < 0.05).

CONCLUSIONS

Artesunate regulates the protein expressions of Fas and Bcl-2 to reduce EOS infiltration in the lung tissue and promote EOS apoptosis in asthmatic mice.

Glycated Hemoglobin A1c, Lung Function, and Hospitalizations Among Adults with Asthma

BACKGROUND

Insulin resistance and metabolic dysfunction have been associated with asthma risk and asthma severity.

OBJECTIVE

To examine the association between glycated hemoglobin A_1c (HbA_1c), asthma-related hospitalizations, and lung function measures among adults in the United Kingdom.

METHODS

A cross-sectional study was conducted of 47,606 adults aged 40 to 69 years who participated in the UK Biobank and had asthma but no diagnosis of diabetes mellitus. HbA_1c level was analyzed as a continuous measure and also categorized as normal (<42 mmol/mol) or as consistent with prediabetes/diabetes (≥42 mmol/mol). An asthma-related hospitalization was defined as ever having had a hospitalization with an International Classification of Diseases, Ninth/Tenth Revision, Clinical Modification code of a main diagnosis compatible with asthma (International Classification of Diseases, Ninth Revision, Clinical Modification code 493.x or International Classification of Diseases, Tenth Revision, Clinical Modification codes J45.x and J46.x). Logistic or linear regression was used for the multivariable analysis of asthma hospitalizations and lung function measures (FEV₁, forced vital capacity [FVC], and FEV₁/FVC). All models were adjusted for age, sex, ethnic background, body mass index, average annual household income, current smoking status, pack-years of smoking, fasting time, and C-reactive protein level.

RESULTS

Both HbA_1c level (odds ratio, 1.03; 95% CI, 1.01-1.04) and an HbA_1c level in the prediabetes/diabetes range (odds ratio, 1.68; 95% CI, 1.18-2.41) were associated with 1 or more asthma hospitalizations. Moreover, both HbA_1c level and an HbA_1c level in the prediabetes/diabetes range were significantly and inversely associated with FEV₁ and FVC.

CONCLUSIONS

HbA_1c is linked to asthma-related hospitalizations and small decrements in FEV₁ and FVC among British adults with asthma but no diagnosis of diabetes mellitus.

Pharmacotherapeutic strategies for critical asthma syndrome: a look at the state of the art

INTRODUCTION

'Critical Asthma Syndrome' (CAS) is an umbrella term proposed to include several forms of asthma, responsible for acute and life-threatening exacerbations. CAS requires urgent and adequate supportive and pharmacological treatments to prevent serious outcomes.

AREAS COVERED

The purpose of this review is to discuss current knowledge on the pharmacotherapeutic strategies for treatment of CAS.

EXPERT OPINION

Airflow limitation, airway wall edema, and mucus plugs are the pathophysiological targets of pharmacological therapies. Strategies to achieve these goals are based on the use of various classes of drugs. Inhaled beta2-agonists are the mainstay of the initial therapy of CAS. Inhaled anticholinergic agents may be considered in the treatment of CAS in addition to beta 2 agonists. Systemic corticosteroids should be administered as soon as possible in order to counteract airway inflammation and restore normal airway sensitivity. The effectiveness of pharmacological therapies in CAS is linked not only to the timely use of drugsbut also to the dosage and route of administration. Early recognition and aggressive treatment are essential for the management of CAS; however, prevention is the best cure. Although significant progress has been made, further efforts are needed to implement an optimal exacerbation prevention strategy.

Pragmatic Markers in the Management of Asthma: A Real-World-Based Approach

Bronchial hyperreactivity, reversible airflow limitation and chronic airway inflammation characterize asthma pathophysiology. Personalized medicine, i.e., a tailored management approach, is appropriate for asthma management and is based on the identification of peculiar phenotypes and endotypes. Biomarkers are necessary for defining phenotypes and endotypes. Several biomarkers have been described in asthma, but most of them are experimental and/or not commonly available. The current paper will, therefore, present pragmatic biomarkers useful for asthma management that are available in daily clinical practice. In this regard, eosinophil assessment and serum allergen-specific IgE assay are the most reliable biomarkers. Lung function, mainly concerning forced expiratory flow at 25-755 of vital capacity (FEF_25-75), and nasal cytology may be envisaged as ancillary biomarkers in asthma management. In conclusion, biomarkers have clinical relevance in asthma concerning both the endotype definition and the personalization of the therapy.

Possible risk factors for poor asthma control assessed in a cross-sectional population-based study from Telemark, Norway

This cross-sectional study of the general population of Telemark County, Norway, aimed to identify risk factors associated with poor asthma control as defined by the Asthma Control Test (ACT), and to determine the proportions of patients with poorly controlled asthma who had undergone spirometry, used asthma medication, or been examined by a pulmonary physician. In 2014–2015, the study recruited 326 subjects aged 16–50 years who had self-reported physician-diagnosed asthma and presence of respiratory symptoms during the previous 12 months. The clinical outcome measures were body mass index (BMI), forced vital capacity (FVC) and forced expiratory volume in one second (FEV₁), fractional exhaled nitric oxide (FeNO), immunoglobulin E (IgE) in serum and serum C-reactive protein (CRP). An ACT score ≤ 19 was defined as poorly controlled asthma. Overall, 113 subjects (35%) reported poor asthma control. The odds ratios (ORs) and 95% confidence intervals (CIs) for factors associated with poorly controlled asthma were: self-reported occupational exposure to vapor, gas, dust, or fumes during the previous 12 months (OR 2.0; 95% CI 1.1–3.6), body mass index ≥ 30 kg/m² (OR 2.2; 95% CI 1.2–4.1), female sex (OR 2.6; 95% CI 1.5–4.7), current smoking (OR 2.8; 95% CI 1.5–5.3), and past smoking (OR 2.3; 95% CI 1.3–4.0). Poor asthma control was also associated with reduced FEV₁ after bronchodilation (β –3.6; 95% CI –7.0 to –0.2). Moreover, 13% of the participants with poor asthma control reported no use of asthma medication, 51% had not been assessed by a pulmonary physician, and 20% had never undergone spirometry. Because these data are cross-sectional, further studies assessing possible risk factors in general and objectively measured occupational exposure in particular are needed. However, our results suggest that there is room for improvement with regards to use of spirometry and pulmonary physician referrals when a patient’s asthma is inadequately controlled.

Systematic Literature Review of Systemic Corticosteroid Use for Asthma Management

Systemic corticosteroid use to manage uncontrolled asthma and its associated healthcare burden may account for important health-related adverse effects. We conducted a systematic literature review to investigate the real-world extent and burden of systemic corticosteroid use in asthma. We searched MEDLINE and Embase databases to identify English-language articles published in 2010–2017, using search terms for asthma with keywords for oral corticosteroids and systemic corticosteroids. Observational studies, prescription database analyses, economic analyses, and surveys on oral/systemic corticosteroid use in children (>5 yr old), adolescents (12–17 yr old), and adults with asthma were included. We identified and reviewed 387 full-text articles, and our review included data from 139 studies. The included studies were conducted in Europe, North America, and Asia. Overall, oral/systemic corticosteroids were commonly used for asthma management and were more frequently used in patients with severe asthma than in those with milder disease. Long-term oral/systemic corticosteroid use was, in general, less frequent than short-term use. Compared with no use, long-term and repeated short-term oral/systemic corticosteroid use were associated with an increased risk of acute and chronic adverse events, even when doses were comparatively low. Greater oral/systemic corticosteroid exposure was also associated with increased costs and healthcare resource use. This review provides a comprehensive overview of oral/systemic corticosteroid use and associated adverse events for patients with all degrees of asthma severity and exposure duration. We report that oral/systemic corticosteroid use is prevalent in asthma management, and the risks of acute and chronic complications increase with the cumulative oral corticosteroid dosage.

Safety of repeated hyperpolarized helium 3 magnetic resonance imaging in pediatric asthma patients

BACKGROUND

Hyperpolarized helium 3 magnetic resonance imaging (³He MRI) is useful for investigating pulmonary physiology of pediatric asthma, but a detailed assessment of the safety profile of this agent has not been performed in children.

OBJECTIVE

To evaluate the safety of ³He MRI in children and adolescents with asthma.

MATERIALS AND METHODS

This was a retrospective observational study. ³He MRI was performed in 66 pediatric patients (mean age 12.9 years, range 8-18 years, 38 male, 28 female) between 2007 and 2017. Fifty-five patients received a single repeated examination and five received two repeated examinations. We assessed a total of 127 ³He MRI exams. Heart rate, respiratory rate and pulse oximetry measured oxygen saturation (SpO₂) were recorded before, during (2 min and 5 min after gas inhalation) and 1 h after MRI. Blood pressure was obtained before and after MRI. Any subjective symptoms were also noted. Changes in vital signs were tested for significance during the exam and divided into three subject age groups (8-12 years, 13-15 years, 16-18 years) using linear mixed-effects models.

RESULTS

There were no serious adverse events, but three minor adverse events (2.3%; headache, dizziness and mild hypoxia) were reported. We found statistically significant increases in heart rate and SpO₂ after ³He MRI. The youngest age group (8-12 years) had an increased heart rate and a decreased respiratory rate at 2 min and 5 min after ³H inhalation, and an increased SpO₂ post MRI.

CONCLUSION

The use of ³He MRI is safe in children and adolescents with asthma.

The asthma evidence base: a call for core outcomes in interventional trials

OBJECTIVES

Biologic therapies are emerging as an option to treat a subset of patients with severe asthma, however no direct comparison between these agents has been conducted. Furthermore, heterogeneity of outcomes in clinical trials makes it difficult to compare these agents and traditional therapies. The extent to which this heterogeneity exists has major implications for evidence-based decisions and is yet to be fully reported. We conducted a literature search to examine outcomes currently being used in clinical trials for asthma.

DATA SOURCES

The Cochrane Library and Clinicaltrials.gov were searched for clinical trials of asthma interventions.

STUDY SELECTIONS

We limited our search to phase 2 through 4 clinical trials in adults, as early-phase trials tend to have pharmacodynamic and pharmacokinetic endpoints as primary outcomes. Interventions for acute exacerbations were excluded.

RESULTS

We identified 117 studies and subsequently identified 111 outcomes. The most prevalent outcomes were asthma control and symptom severity, FEV1, and change in ACQ scale. Twenty patient-reported outcomes instruments were identified and de-facto standard asthma outcomes and PROs were under-reported in examined literature. Existing quality of life tools did not capture the day-to-day experience or the unique treatment burden from oral corticosteroids for patient with severe asthma. Compounding the absence of trials directly comparing therapies, the significant variation we identified in outcome definitions and measurement create hurdles to effectively compare traditional and biologic therapies.

CONCLUSION

With the growing number of clinical trials evaluating advanced therapies such as biologics, a wide range of primary and secondary outcomes are evaluated. A core outcome set created by relevant stakeholders is needed to collectively evaluate pooled outcomes in order to allow more meaningful comparisons of asthma therapies and to incorporate the patient experience.

Needs for Systems Approaches to Better Treat Individuals With Severe Asthma: Predicting Phenotypes and Responses to Treatments

Asthma is a frequent heterogeneous multifactorial chronic disease whose severe forms remain largely uncontrolled despite the availability of many drugs and educational therapy. Several phenotypes and endotypes of severe asthma have been described over the last two decades. Typical type-2-immunity-driven asthma remains the most frequent phenotype, and several targeted therapies have been developed and are now available. On the contrary, non-type-2 immunity-driven severe asthma is less understood and still requires efficient innovative therapies. A personalized approach would allow improving asthma control with the help of robust biomarkers able to predict phenotypes/endotypes, exacerbations, response to targeted treatments and, in the future, possible curative options. Some data from large multicenter cohorts have emerged in recent years, especially in transcriptomics. These data have to be integrated and reproduced longitudinally to provide a systems approach for asthma care. In this focused review, the needs for such an approach and the available data will be reviewed as well as the next steps for achieving personalized medicine in asthma.

A real-world assessment of asthma with chronic rhinosinusitis

BACKGROUND

Chronic rhinosinusitis (CRS) includes 2 main phenotypes: CRS without nasal polyps (CRSsNP) and CRS with nasal polyps (CRSwNP). CRS has been reported to be a comorbidity of asthma.

OBJECTIVE

This study aimed to investigate the role of CRS in outpatients with asthma visited in real-world setting.

METHODS

This cross-sectional study enrolled 499 consecutive outpatients with asthma. Age, sex, body mass index, smoking status, lung function, Asthma Control Test, inflammatory type 2 biomarkers (including fractional exhaled nitric oxide, blood eosinophils, serum total immunoglobulin E, and allergy), treatment step according to the Global Initiative for Asthma, and comorbidities (obstructive sleep apnea syndrome, arterial hypertension, bronchiectasis, diabetes mellitus type 2, and osteoporosis) were evaluated.

RESULTS

A total of 179 (35.87%) patients had CRS, in particular 93 (18.64%) had CRSsNP and 86 (17.23%) had CRSwNP. Type 2 inflammation (defined by at least 1 positive biomarker) was present in 81.44% of patients (fractional exhaled nitric oxide > 30 parts per billion in 46.9%, blood eosinophil count > 300 cell/μL in 39.67%, serum total immunoglobulin E >100 IU/mL in 51.54%, and allergy in 53.71%). By multivariate analysis, type 2 inflammation and blood eosinophils greater than 300 cell/μL were the main predictors (odds ratio [OR] 2.54 and 2.26, respectively) of CRS-asthma association. In particular, CRSwNP comorbidity was predicted by type 2 inflammation (OR 3.4) and blood eosinophils greater than 300 cell/μL (OR 3.0). Smoking had conflicting outcome.

CONCLUSION

This study confirmed that CRS is a frequent asthma comorbidity because it affects more than one-third of outpatients with asthma. CRSwNP is associated with type 2 inflammation and blood eosinophilia. These outcomes underline that CRSwNP asthma phenotype deserves adequate attention for careful management and optimal identification of the best-tailored therapy.

Latent Class Analysis of School-Age Children at Risk for Asthma Exacerbation

BACKGROUND

Factors responsible for asthma exacerbations in children are complex and may differ from those that drive asthma severity.

OBJECTIVE

To identify latent classes of children at risk for asthma exacerbation and determine whether latent class assignment is useful in the prediction of future exacerbation.

METHODS

Latent class analysis was performed on 513 children aged 6 to 17 years at risk for asthma exacerbation, with 31 variables encompassing demographics, medical history, treatment, symptoms, lung function, sensitization, and type 2 inflammation. Primary and secondary outcomes included exacerbation occurrence by 12 months and time to first exacerbation, respectively.

RESULTS

Four latent classes were identified with differing demographic features, sensitization and type 2 inflammatory markers, prior exacerbation severity and health care utilization, and lung function. Exacerbations occurred in 22.4% of class 1 ("lesser sensitization with normal lung function"), 27.9% of class 2 ("lesser sensitization with prior severe exacerbation and normal lung function"), 45.3% of class 3 ("multiple sensitization with reversible airflow limitation"), and 64.3% of class 4 ("multiple sensitization with partially reversible airflow limitation") (P < .001). Time to exacerbation also followed similar trends and was shortest in the latent classes with multiple sensitization and airflow limitation (P < .001). Outcomes were driven largely by children with exacerbation-prone asthma (defined as ≥3 exacerbations in the prior year), who were present in each class but most strongly represented in classes 3 and 4.

CONCLUSIONS

Children at risk for asthma exacerbation are a heterogeneous group. Sensitization, prior exacerbation severity, and lung function variables may be particularly useful in identifying children at greatest risk for future exacerbation.

Ventilation defects on hyperpolarized helium-3 MRI in asthma are predictive of 2-year exacerbation frequency

BACKGROUND

There is an unmet need for an objective biomarker to predict asthma exacerbations.

OBJECTIVE

Our aim was to assess the ventilation defect percent (VDP) on hyperpolarized helium-3 magnetic resonance imaging as a predictor of exacerbation frequency following imaging.

METHODS

Subjects underwent hyperpolarized helium-3 and conventional clinical measurements, including pulmonary function tests, during a period of disease stability, and exacerbations were recorded prospectively over the following 2 years. We used a Poisson regression tree model to estimate an optimal VDP threshold for classifying subjects into high- versus low-exacerbation groups and then used statistical regression to compare this VDP threshold against conventional clinical measures as predictors of exacerbations.

RESULTS

A total of 67 individuals with asthma (27 males and 40 females, 28 with mild-to-moderate asthma and 39 with severe asthma) had a median VDP of 3.75% (1.2% [first quartile]-7.9% [third quartile]). An optimal VDP threshold of 4.28% was selected on the basis of the maximum likelihood estimation of the regression tree model. Subjects with a VDP greater than 4.28% (n = 32) had a median of 1.5 exacerbations versus 0.0 for subjects with a VDP less than 4.28% (n = 35). In a stepwise multivariate regression model, a VDP greater than 4.28% was associated with an exacerbation incidence rate ratio of 2.5 (95% CI = 1.3-4.7) versus a VDP less than or equal to 4.28%. However, once individual medical history was included in the model, VDP was no longer significant. Nonetheless, VDP may provide an objective and complementary quantitative marker of individual exacerbation risk that is useful for monitoring individual change in disease status, selecting patients for therapy, and assessing treatment response.

CONCLUSION

VDP measured with magnetic resonance imaging shows promise as a biomarker of prospective asthma exacerbations.

In Vivo Allergen-Activated Eosinophils Promote Collagen I and Fibronectin Gene Expression in Airway Smooth Muscle Cells via TGF-β1 Signaling Pathway in Asthma

Eosinophils infiltration and releasing TGF-β1 in the airways has been implicated in the pathogenesis of asthma, especially during acute episodes provoked by an allergen. TGF-β1 is a major mediator involved in pro-inflammatory responses and fibrotic tissue remodeling in asthma. We aimed to evaluate the effect of in vivo allergen-activated eosinophils on the expression of COL1A1 and FN in ASM cells in asthma. A total of 12 allergic asthma patients and 11 healthy subjects were examined. All study subjects underwent bronchial challenge with D. pteronyssinus allergen. Eosinophils from peripheral blood were isolated before and 24 h after the bronchial allergen challenge using high-density centrifugation and magnetic separation. Individual co-cultures of blood eosinophils and immortalized human ASM cells were prepared. The TGF-β1 concentration in culture supernatants was analyzed using ELISA. Gene expression was analyzed using qRT-PCR. Eosinophils integrins were suppressed with linear RGDS peptide before co-culture with ASM cells. Results: The expression of TGF-β1 in asthmatic eosinophils significantly increased over non-activated asthmatic eosinophils after allergen challenge, p < 0.001. The TGF-β1 concentration in culture supernatants was significantly higher in samples with allergen-activated asthmatic eosinophils compared to baseline, p < 0.05. The effect of allergen-activated asthmatic eosinophils on the expression of TGF-β1, COL1A1, and FN in ASM cells was more significant compared to non-activated eosinophils, p < 0.05, however, no difference was found on WNT-5A expression. The incubation of allergen-activated asthmatic eosinophils with RGDS peptide was more effective compared to non-activated eosinophils as the gene expression in ASM cells was downregulated equally to the same level as healthy eosinophils.

Inflammatory mechanisms linking maternal and childhood asthma

Asthma is a chronic inflammatory airway disease characterized by airway hyperresponsiveness, inflammation, and remodeling. Asthma often develops during childhood and causes lifelong decrements in lung function and quality of life. Risk factors for childhood asthma are numerous and include genetic, epigenetic, developmental, and environmental factors. Uncontrolled maternal asthma during pregnancy exposes the developing fetus to inflammatory insults, which further increase the risk of childhood asthma independent of genetic predisposition. This review focuses on the role of maternal asthma in the development of asthma in offspring. We will present maternal asthma as a targetable and modifiable risk factor for childhood asthma and discuss the mechanisms by which maternal inflammation increases childhood asthma risk. Topics include how exposure to maternal asthma in utero shapes structural lung development with a special emphasis on airway nerves, how maternal type-2 cytokines such as IL-5 activate the fetal immune system, and how changes in lung and immune cell development inform responses to aero-allergens later in life. Finally, we highlight emerging evidence that maternal asthma establishes a unique "asthma signature" in the airways of children, leading to novel mechanisms of airway hyperreactivity and inflammatory cell responses.

Clinical factors associated with acute exacerbations of chronic rhinosinusitis

BACKGROUND

Chronic rhinosinusitis (CRS) is complicated by frequent acute exacerbations leading to significant health care burden and impaired quality of life.

OBJECTIVE

The objective of this study was to identify clinical factors associated with frequent acute exacerbation of CRS (AECRS).

METHODS

This is a retrospective cohort study of patients with CRS from January 1, 2014, to May 31, 2016. Frequent AECRS was defined as at least 4 episodes over a 12-month period in which an antibiotic was prescribed for worsening sinus symptoms, and infrequent AECRS was defined as 0 to 3 episodes. Clinical factors, including asthma, allergic rhinitis, eosinophil count of at least 150 cells per microliter, and autoimmune disease, were evaluated for associations between the 2 groups.

RESULTS

Of the 3109 patients with CRS who were identified, 600 (19.3%) were classified as having frequent exacerbation. Asthma, allergic rhinitis, eosinophil count of at least 150 cells per microliter, and autoimmune disease were associated with frequent AECRS with statistically significant adjusted odds ratios (aORs) after controlling for age, race, and sex in multivariate analysis (asthma aOR = 2.61 [95% CI = 2.14-3.18]; allergic rhinitis aOR = 1.96 [95% CI = 1.58-2.42]; eosinophil count of at least 150 cells per microliter aOR = 1.54 [95% CI = 1.21-1.97]; and autoimmune disease aOR = 1.68 [95% CI = 1.36-2.07]). Antibody deficiency, antibiotic allergy, lower FEV₁, radiographic sinus disease severity, nasal polyposis, and systemic corticosteroid use were also associated with frequent AECRS.

CONCLUSION

Patients with frequent episodes of AECRS were characterized by a higher prevalence of asthma, allergic rhinitis, eosinophil count of at least 150 cells per microliter, autoimmune disease, and other allergic and immunologic diseases. These findings identify a high-risk phenotype of patients with CRS for preventive interventions to reduce exacerbation frequency.

Three Major Efforts to Phenotype Asthma: Severe Asthma Research Program, Asthma Disease Endotyping for Personalized Therapeutics, and Unbiased Biomarkers for the Prediction of Respiratory Disease Outcome

The SARP, ADEPT, and U-BIOPRED programs are all significant efforts in characterizing asthma and reporting clusters that will assist in designing personalized therapies for asthma, and especially severe asthma. Key aspects of the design of these programs are summarized and major findings are reported in this review.

HSD3B1 genotype identifies glucocorticoid responsiveness in severe asthma

Asthma resistance to glucocorticoid treatment is a major health problem with unclear etiology. Glucocorticoids inhibit adrenal androgen production. However, androgens have potential benefits in asthma. HSD3B1 encodes for 3β-hydroxysteroid dehydrogenase-1 (3β-HSD1), which catalyzes peripheral conversion from adrenal dehydroepiandrosterone (DHEA) to potent androgens and has a germline missense-encoding polymorphism. The adrenal restrictive HSD3B1(1245A) allele limits conversion, whereas the adrenal permissive HSD3B1(1245C) allele increases DHEA metabolism to potent androgens. In the Severe Asthma Research Program (SARP) III cohort, we determined the association between DHEA-sulfate and percentage predicted forced expiratory volume in 1 s (FEV1PP). HSD3B1(1245) genotypes were assessed, and association between adrenal restrictive and adrenal permissive alleles and FEV1PP in patients with (GC) and without (noGC) daily oral glucocorticoid treatment was determined (n = 318). Validation was performed in a second cohort (SARP I&II; n = 184). DHEA-sulfate is associated with FEV1PP and is suppressed with GC treatment. GC patients homozygous for the adrenal restrictive genotype have lower FEV1PP compared with noGC patients (54.3% vs. 75.1%; P < 0.001). In patients with the homozygous adrenal permissive genotype, there was no FEV1PP difference in GC vs. noGC patients (73.4% vs. 78.9%; P = 0.39). Results were independently confirmed: FEV1PP for homozygous adrenal restrictive genotype in GC vs. noGC is 49.8 vs. 63.4 (P < 0.001), and for homozygous adrenal permissive genotype, it is 66.7 vs. 67.7 (P = 0.92). The adrenal restrictive HSD3B1(1245) genotype is associated with GC resistance. This effect appears to be driven by GC suppression of 3β-HSD1 substrate. Our results suggest opportunities for prediction of GC resistance and pharmacologic intervention.

Current and Future Treatments of Rhinitis and Sinusitis

Advances in understanding the pathogenic mechanisms of both rhinitis and chronic rhinosinusitis have resulted in new treatment options, especially for chronic rhinosinusitis. A review of relevant medical and surgical clinical studies shows that intranasal corticosteroids, antihistamines, and allergen immunotherapy continue to be the best treatments for chronic rhinitis. Dupilumab is the first biologic approved for chronic rhinosinusitis with polyps. Omalizumab, mepolizumab, and benralizumab may have a future role in the treatment of chronic rhinosinusitis. Novel corticosteroid delivery devices such as an exhalation delivery system for fluticasone and bioabsorbable sinus implants provide enhanced and localized distribution of corticosteroids. Surgical management tailored to the underlying disease process improves clinical outcomes in chronic rhinosinusitis with or without nasal polyposis. Advances in the understanding of the heterogeneous nature of rhinitis and rhinosinusitis have resulted in more precise treatments. Improving the understanding of different endotypes should provide better knowledge to determine appropriate current and new therapies to treat these diseases.

Strategies to prevent exacerbations of childhood asthma

PURPOSE OF REVIEW

The goal of this review is to discuss strategies to prevent asthma exacerbations in children, focusing on recent advances in knowledge and understanding.

RECENT FINDINGS

Asthma exacerbations are common, and their prevention is an important goal to avoid detrimental impacts such as loss of disease control and lung function and significant healthcare costs. A number of strategies have been studied as tools for prevention of asthma exacerbations. Daily inhaled corticosteroids (ICSs) are effective for many children with asthma. However, alternative strategies such as intermittent ICS therapy, antileukotrienes, and biologics have been studied as means to lessen corticosteroid exposure. Further, recent studies have examined add-on strategies for children not controlled with ICS alone. Finally, personalizing therapy with targeted approaches has provided significant benefit to those with moderate-severe disease.

SUMMARY

Recent research highlights many potentially effective treatment strategies to prevent asthma exacerbations in children. We have reviewed and summarized the data on treatment approaches to help provide a better understanding of the methods that can be utilized. An individualized approach with careful monitoring is essential to identify the most effective strategies to prevent asthma exacerbations in each child.

Longitudinal trajectories of severe wheeze exacerbations from infancy to school age and their association with early-life risk factors and late asthma outcomes

INTRODUCTION

Exacerbation-prone asthma subtype has been reported in studies using data-driven methodologies. However, patterns of severe exacerbations have not been studied.

OBJECTIVE

To investigate longitudinal trajectories of severe wheeze exacerbations from infancy to school age.

METHODS

We applied longitudinal k-means clustering to derive exacerbation trajectories among 887 participants from a population-based birth cohort with severe wheeze exacerbations confirmed in healthcare records. We examined early-life risk factors of the derived trajectories, and their asthma-related outcomes and lung function in adolescence.

RESULTS

498/887 children (56%) had physician-confirmed wheeze by age 8 years, of whom 160 had at least one severe exacerbation. A two-cluster model provided the optimal solution for severe exacerbation trajectories among these 160 children: "Infrequent exacerbations (IE)" (n = 150, 93.7%) and "Early-onset frequent exacerbations (FE)" (n = 10, 6.3%). Shorter duration of breastfeeding was the strongest early-life risk factor for FE (weeks, median [IQR]: FE, 0 [0-1.75] vs. IE, 6 [0-20], P < .001). Specific airway resistance (sR_aw ) was significantly higher in FE compared with IE trajectory throughout childhood. We then compared children in the two exacerbation trajectories with those who have never wheezed (NW, n = 389) or have wheezed but had no severe exacerbations (WNE, n = 338). At age 8 years, FEV₁ /FVC was significantly lower and FeNO significantly higher among FE children compared with all other groups. By adolescence (age 16), subjects in FE trajectory were significantly more likely to have current asthma (67% FE vs. 30% IE vs. 13% WNE, P < .001) and use inhaled corticosteroids (77% FE vs. 15% IE vs. 18% WNE, P < .001). Lung function was significantly diminished in the FE trajectory (FEV₁ /FVC, mean [95%CI]: 89.9% [89.3-90.5] vs. 88.1% [87.3-88.8] vs. 85.1% [83.4-86.7] vs. 74.7% [61.5-87.8], NW, WNE, IE, FE respectively, P < .001).

CONCLUSION

We have identified two distinct trajectories of severe exacerbations during childhood with different early-life risk factors and asthma-related outcomes in adolescence.

Obesity Does Not Increase the Risk of Asthma Readmissions

The relationship between obesity and asthma exacerbations is still under debate. The aim of our work is to analyse the relationship between obesity and hospital re-admissions in asthmatics. A review was retrospectively performed on all hospital admissions of adult patients due to asthma exacerbation occurring in our hospital for 11 years. All those cases with asthma as the first diagnosis in the discharge report were included, or those with asthma as the second diagnosis provided when the first diagnosis was respiratory infection or respiratory failure. Only the first hospital admission of each patient was included in this study. The Odds Ratios of a higher incidence of early/late readmissions due to asthma exacerbation were calculated using a binary logistic regression, using the body mass index (BMI) as independent variable, adjusted for all the variables included in the study. The study included 809 patients with a mean age of 55.6 years, and 65.2% were female. The majority (71.4%) were obese or overweight. No significant relationship was observed in the univariate or multivariate analyses between overweight or obesity and the early or late hospital readmissions due to asthma. Therefore, obesity does not seem to be a determining factor in the risk of asthma exacerbations.

Mechanisms and Management of Asthma Exacerbations

Acute asthma remains an important medical emergency, the most frequent cause of acute admissions in children and a major source of morbidity for adults with asthma. In all ages with asthma, the presence of exacerbations is an important defining characteristic of asthma severity. In this review, we assess the epidemiology of acute asthma, the triggers of acute exacerbations, and the mechanisms that underlie these exacerbations. We also assess current treatments that prevent exacerbations, with an emphasis on the role of type 2 airway inflammation in the context of acute exacerbations and the novel treatments that effectively target this. Finally we review current management strategies of the exacerbations themselves.

Severe Asthma in Childhood

Severe asthma is broadly defined as asthma requiring a high level of therapy, usually high doses of inhaled corticosteroids, to bring under control. Children who remain symptomatic despite such treatment are a heterogeneous population, and bear a high burden of disease and require high resource utilization. Children with severe asthma require a comprehensive evaluation, careful consideration of alternative diagnoses and comorbid conditions, assessment of medication adherence and environmental conditions, and frequent disease monitoring.

Comorbidities associated with severe asthma

Background:

Severe asthma can be a challenging disease to manage by the provider and by the patient, supported by evidence of increased health-care utilization by this population. Patients with severe asthma should be screened for comorbidities because these often contribute to poorly controlled asthma. The impact of comorbidities, however, are not completely understood.

Objective:

To review common comorbidities and their impact on severe asthma.

Methods:

A review of relevant clinical research studies that examined comorbidities in severe or difficult-to-treat asthma.

Results:

A number of comorbid diseases, including rhinitis, rhinosinusitis, gastroesophageal reflux, and obstructive sleep apnea, are associated with severe or difficult-to-treat asthma. If present and untreated, these conditions may adversely affect asthma control, quality of life, and/or lung function, despite adequate treatment with step-up asthma controller therapy.

Conclusion:

Treatable comorbidities are associated with severe and difficult-to-control asthma. Failure to recognize these comorbidities may divert appropriate care and increase disease burden. Assessment and management of these risk factors may contribute to improved asthma outcome; however, more investigation is needed to understand the relationship of comorbidities and asthma due to inconsistency in the findings.

Exacerbation-Prone Asthma

Patients who are prone to exacerbations of asthma experience significant costs in terms of missed work and school, acute care visits, and hospitalizations. Exacerbations are largely driven by environmental exposures including pollutants, stress, and viral and bacterial pathogens. These exposures are most likely to induce acute severe "asthma attacks" in high-risk patients. These personal risk factors for exacerbations can vary with the phenotype of asthma and age of the patient. In children, allergic sensitization is a strong risk factor, especially for those children who develop sensitization early in life. Airway inflammation is an important risk factor, and biomarkers are under evaluation for utility in detecting eosinophilic and type 2 inflammation and neutrophilic inflammation as indicators of risk for recurrent exacerbations. Insights into inflammatory mechanisms have led to new approaches to prevent exacerbations using mAb-based biologics that target specific type 2 pathways. Challenges remain in developing an evidence base to support precision interventions with these effective yet expensive therapies, and in determining whether these treatments will be safe and effective in young children. Unfortunately, there has been less progress in developing treatments for acute exacerbations. Hopefully, greater understanding of mechanisms relating airway viruses, bacteria, mucin production, and neutrophilic inflammatory responses will lead to additional treatment options for patients experiencing acute exacerbations.