Difficult/therapy-resistant asthma: the need for an integrated approach to define clinical phenotypes, evaluate risk factors, understand pathophysiology and find novel therapies. ERS Task Force on Difficult/Therapy-Resistant Asthma. European Respiratory Society

Paroxysmal dyspnoea in asthma: Wheeze, ILO or dysfunctional breathing?

Paroxysms of dyspnoea in the general population are commonly reported and are frequently assumed to be asthma-related, especially if this diagnostic label has been previously applied. Often, this is not the case. Inducible Laryngeal Obstruction (ILO) and Dysfunctional Breathing (DB) are common comorbid conditions that go unrecognised in many difficult-to-treat asthmatics. On average, these patients have a delay in diagnosis of almost 5 years. This delay, along with ineffective, inappropriate escalation of asthma therapy, frequent hospital presentations for uncontrolled symptoms, and even intensive care admissions, magnifies patient morbidity and poor quality of life. ILO and DB have similar presentations and triggers to asthma. Differentiating between them can be challenging, especially in centres that do not have access to multidisciplinary subspecialty asthma services. Objectively confirming the diagnosis can likewise be challenging as symptoms fluctuate, and gold-standard investigations require extensive experience. This mini-review will summarise the clinical features of ILO and DB, with particular focus in the context of individuals treated for asthma. This narrative review will define each condition, highlight poignant aspects of the history and describe elements of the diagnostic pathway to gain objective confirmation.

Does the Use of Asthma-Controller Medication in Accordance with Guidelines Reduce the Incidence of Acute Exacerbations and Healthcare Costs?

Background

In asthma, consistent control of chronic airway inflammation is crucial, and the use of asthma-controller medication has been emphasized. Our purpose in this study is to compare the incidence of acute exacerbation and healthcare costs related to the use of asthma-controller medication.

Methods

By using data collected by the National Health Insurance Review and Assessment Service, we compared one-year clinical outcomes and medical costs from July 2014 to June 2015 (follow-up period) between two groups of patients with asthma who received different prescriptions for recommended asthma-controller medication (inhaled corticosteroids or leukotriene receptor antagonists) at least once from July 2013 to June 2014 (assessment period).

Results

There were 51,757 patients who satisfied our inclusion criteria. Among them, 13,702 patients (26.5%) were prescribed a recommended asthma-controller medication during the assessment period. In patients using a recommended asthma-controller medication, the frequency of acute exacerbations decreased in the follow-up period, from 2.7% to 1.1%. The total medical costs of the controller group decreased during the follow-up period compared to the assessment period, from $3,772,692 to $1,985,475. Only 50.9% of patients in the controller group used healthcare services in the follow-up period, and the use of asthma-controller medication decreased in the follow-up period.

Conclusion

Overall, patients using a recommended asthma-controller medication showed decreased acute exacerbation and reduced total healthcare cost by half.

Severe pediatric asthma therapy: Omalizumab-A systematic review and meta-analysis of efficacy and safety profile

Background

Omalizumab is the first biological therapy used to treat moderate-to-severe asthma and certainly the one with the highest number of publications.

Methods

A systematic review and meta-analysis were performed to examine two critical outcomes of omalizumab therapy, asthma exacerbation rate, the reduction of the use of inhaled corticosteroids (ICS), and the improvement of the lung function as a secondary outcome using the following keywords in the MEDLINE database: "anti-IgE, severe asthma, children, and randomized controlled trial." We specifically selected papers that included moderate-to-severe asthma patients and collected data on children and adolescents.

Results

Four RCT studies (total number of patients = 1,239) were included in the analysis. The reported data on exacerbations showed an overall improvement in the exacerbation rate with a decreased use of inhaled steroids and some other minimal clinically important difference (MCID).

Conclusions

Our systematic review confirms the known findings that omalizumab therapy decreases asthma exacerbation rate and reduces background therapy inhaled steroid dose. Therefore, add-on therapy with omalizumab shows a good efficacy and safety profile, thus proving to be a useful additional therapeutic option.

Systematic Review Registration

https://www.crd.york.ac.uk/prospero/, identifier: CRD42023396785.

Leukotriene B4 Receptors Are Necessary for the Stimulation of NLRP3 Inflammasome and IL-1β Synthesis in Neutrophil-Dominant Asthmatic Airway Inflammation

The stimulation of the NOD-, LRR- and pyrin domain-containing protein 3 (NLRP3) inflammasome and IL-1β synthesis are associated with chronic respiratory diseases such as neutrophil-dominant severe asthma. Leukotriene B₄ (LTB₄) is a principal chemoattractant molecule for neutrophil recruitment, and its receptors BLT1 and BLT2 have been suggested to contribute to neutrophil-dominant asthmatic airway inflammation. However, the relationship between BLT1/2 and NLRP3 in neutrophil-dominant asthmatic airway inflammation has not been previously studied. In the present study, we investigated whether BLT1/2 play any roles in stimulating the NLRP3 inflammasome and IL-1βsynthesis. The blockade of BLT1 or BLT2 clearly suppressed the stimulation of the NLRP3 inflammasome and IL-1β synthesis in house dust mite (HDM)/lipopolysaccharide (LPS)-induced neutrophilic airway inflammation. The enzymes 5-lipoxygenase and 12-lipoxygenase, which catalyze the synthesis of BLT1/2 ligands [LTB₄, 12(S)-hydroxyeicosatetraenoic acid (12(S)-HETE), and 12-hydroxyheptadecatreinoic acid (12-HHT)], were also critically associated with the stimulation of NLRP3 and IL-1β synthesis. Together, our results suggest that the 5-/12-LOX-BLT1/2-linked cascade are necessary for the simulation of the NLRP3 inflammasome and IL-1β synthesis, thus contributing to HDM/LPS-induced neutrophil-dominant airway inflammation.

A child with a foreign body in bronchus misdiagnosed as asthma

Foreign body ingestion should be considered as an important differential in a child with difficult asthma. We report an 11-year-old male child with foreign body aspiration who initially was diagnosed and treated as difficult asthma. Later on, he was diagnosed to have a foreign body in the right bronchus, which was successfully removed by flexible bronchoscopy.

The Hidden Burden of Severe Asthma: From Patient Perspective to New Opportunities for Clinicians

Severe asthma is an important topic in respiratory diseases, due to its high impact on morbidity and mortality as well as on health-care resources. The many challenges that still exist in the management of the most difficult-to-treat forms of the disease, and the acknowledgement of the existence of unexplored areas in the pathophysiological mechanisms and the therapeutic targets represent an opportunity to gather experts in the field with the immediate goals to summarize current understanding about the natural history of severe asthma and to identify gaps in knowledge and research opportunities, with the aim to contribute to improved medical care and health outcomes. This article is a consensus document from the “International Course on Severe Asthma” that took place in Palermo, Italy, on May 10–11, 2019. Emerging topics in severe asthma were addressed and discussed among experts, with special focus on patient’s needs and research opportunities, with the aim to highlight the unanswered questions in the diagnostic process and therapeutic approach.

Patient perceived barriers to exercise and their clinical associations in difficult asthma

BACKGROUND

Exercise is recommended in guidelines for asthma management and has beneficial effects on symptom control, inflammation and lung function in patients with sub-optimally controlled asthma. Despite this, physical activity levels in patients with difficult asthma are often impaired. Understanding the barriers to exercise in people with difficult asthma is crucial for increasing their activity, and in implementing successful, disease modifying, and holistic approaches to improve their health.

METHODS

62 Patients within the WATCH Difficult Asthma Cohort (Southampton, UK) completed an Exercise Therapy Burden Questionnaire (ETBQ). The results were analyzed with contemporaneous asthma-related data to determine relationships between perceived exercise barriers and asthma and comorbidity characteristics.

RESULTS

Patients were reflective of a difficult asthma cohort, 66% were female, and 63% were atopic. They had a high BMI (median [inter-quartile range]) of 29.3 [25.5-36.2], age of 53.5 [38.75, 65.25], impaired spirometry with FEV1 73% predicted [59.5, 86.6%] and FEV/FVC ratio of 72 [56.5, 78.0] and poor symptom control, as defined by an Asthma Control Questionnaire (ACQ6) result of 2.4 [1.28, 3.2]. A high perceived barriers to exercise score was significantly correlated with increased asthma symptoms (r = 0.452, p < 0.0001), anxiety (r = 0.375, p = 0.005) and depression (r = 0.363, p = 0.008), poor quality of life (r = 0.345, p = 0.015) and number of rescue oral steroid courses in the past 12 months (r = 0.257, p = 0.048). Lung function, blood eosinophil count, FeNO, Njimegen and SNOT22 scores, BMI and hospitalisations in the previous year were not related to exercise perceptions.

CONCLUSION

In difficult asthma, perceived barriers to exercise are related to symptom burden and psychological morbidity. Therefore, exercise interventions combined with psychological input such as CBT to restructure thought processes around these perceived barriers may be useful in facilitating adoption of exercise.

Severe asthma and eligibility for biologics in a Brazilian cohort

OBJECTIVE

This study aims to describe the eligibility for biologic therapies for severe asthma (SA) in a cohort of patients attending the Program for Control of Asthma (ProAR) in Bahia, Brazil.

METHODS

Data from SA patients (≥18 years old) attending the ProAR, that were included in a case-control study conducted from 2013 to 2015, were used to reassess patients according to a modified ERS/ATS 2014 SA criteria. Patients were then classified according to the eligibility for SA biological therapy based on current prescription labels.

RESULTS

From 544 patients in the cohort, 531 (97.6%) were included and 172 (32.4%) were identified as SA patients according to the ERS/ATS 2014 modified criteria. Of these 172 patients, 69 (40.1%) were ineligible for any of the biologicals approved for asthma (omalizumab, mepolizumab, reslizumab and benralizumab), 60 (34.9%) patients were eligible for one of the biological therapies, and 10 (5.8%) patients were eligible for all biological therapies.

CONCLUSIONS

More than half of patients with SA were eligible for biologic therapy in our study, but none of them received this form of treatment. Almost half of them were not eligible to any of the approved biologics, however. The variability and overlap in patients' eligibility highlight the importance of evaluating each patient individually for a more personalized treatment approach. While there is a need to increase access for some of those eligible that may really need a biologic treatment, continuous efforts are required to develop alternatives to those who are not eligible.

3D printing for tissue engineering in otolaryngology

Airway and other head and neck disorders affect hundreds of thousands of patients each year and most require surgical intervention. Among these, congenital deformity that affects newborns is particularly serious and can be life-threatening. In these cases, reconstructive surgery is resolutive but bears significant limitations, including the donor site morbidity and limited available tissue. In this context, tissue engineering represents a promising alternative approach for the surgical treatment of otolaryngologic disorders. In particular, 3D printing coupled with advanced imaging technologies offers the unique opportunity to reproduce the complex anatomy of native ear, nose, and throat, with its import in terms of functionality as well as aesthetics and the associated patient well-being. In this review, we provide a general overview of the main ear, nose and throat disorders and focus on the most recent scientific literature on 3D printing and bioprinting for their treatment.

Protocol for a multicentre randomised controlled trial to investigate the effect on asthma-related quality of life from breathing retraining in patients with incomplete asthma control attending specialist care in Denmark

INTRODUCTION AND AIM

Uncontrolled asthma is a global health challenge with substantial impact on quality of life (QoL) and overall healthcare costs. Unrecognised and/or unmanaged comorbidities often contribute to presence of uncontrolled asthma. Abnormalities in breathing pattern are termed dysfunctional breathing and are not only common in asthma but also lead to asthma-like symptoms and reduced QoL, and, in keeping with this, improvement with breathing normalisation. Evidence-based guidelines recommend breathing retraining interventions as an adjuvant treatment in uncontrolled asthma. Physiotherapy-based breathing pattern modification interventions incorporating relaxation have been shown to improve asthma-related QoL in primary care patients with impaired asthma control. Despite anecdotal reports, effectiveness of breathing retraining in patients referred to secondary care with incomplete asthma control has not been formally assessed in a randomised controlled trial (RCT). We aim to investigate the effect of breathing exercises on asthma-related QoL in patients with incomplete asthma control despite specialist care.

METHODS AND ANALYSIS

This two-armed assessor-blinded multicentre RCT will investigate the effect of physiotherapist-delivered breathing retraining on asthma QoL questionnaire (MiniAQLQ) in addition to usual specialist care, recruiting from seven outpatient departments and one specialised clinic representing all regions of Denmark during 2017-2019. We will include 190 consenting adults with incomplete asthma control, defined as Asthma Control Questionnaire 6-item score ≥0.8. Participants will randomly be allocated to either breathing exercise programme in addition to usual care (BrEX +UC) or UC alone. BrEX compiles three physiotherapy sessions and encouragement to perform home exercise daily. Both groups continue usual secondary care management. Primary outcome is between-group difference in MiniAQLQ at 6 months. Secondary outcomes include patient-reported outcome measures, spirometry and accelerometer.

ETHICS AND DISSEMINATION

Ethics Committee, Region Zealand (SJ-552) and Danish Data Protection Agency (REG-55-2016) approved the trial. Results will be reported in peer-reviewed scientific journals.

TRIAL REGISTRATION NUMBER

NCT03127059; Pre-results.

Recent Advances in Severe Asthma: From Phenotypes to Personalized Medicine

This review focuses on recent clinical and translational discoveries in severe and uncontrolled asthma that now enable phenotyping and personalized therapies in these patients. Although asthma is common in both children and adults and typically responds to standard therapies, a subset of individuals with asthma experience severe and/or persistent symptoms despite appropriate therapies. Airflow obstruction leading to frequent symptoms requiring higher levels of controller therapy is the cardinal feature of severe asthma, but the underlying molecular mechanisms, or endotypes, are diverse and variable between individuals. Two major risk factors that contribute to severe asthma are genetics and environmental exposures that modulate immune responses, and although these often interact in complex manners that are not fully understood, certain endotypes converge in severe asthma. A number of studies have evaluated various features of patients with severe asthma and classified patients into phenotypes with clinical relevance. This phenotyping is now incorporated into clinical practice and can be used to guide advanced biological therapies that target specific molecules and inflammatory pathways that contribute to asthma pathogenesis.

Protocol for the Wessex AsThma CoHort of difficult asthma (WATCH): a pragmatic real-life longitudinal study of difficult asthma in the clinic

Background

Asthma is now widely recognised to be a heterogeneous disease. The last two decades have seen the identification of a number of biological targets and development of various novel therapies. Despite this, asthma still represents a significant health and economic burden worldwide. Why some individuals should continue to suffer remains unclear.

Methods

The Wessex Asthma Cohort of Difficult Asthma (WATCH) is an ongoing ‘real-life’, prospective study of patients in the University Hospital Southampton Foundation Trust (UHSFT) Difficult Asthma service. Research data capture is aligned with the extensive clinical characterisation required of a commissioned National Health Service (NHS) Specialist Centre for Severe Asthma. Data acquisition includes detailed clinical, health and disease-related questionnaires, anthropometry, allergy and lung function testing, radiological imaging (in a small subset) and collection of biological samples (blood, urine and sputum). Prospective data are captured in parallel to clinical follow up appointments, with data entered into a bespoke database.

Discussion

The pragmatic ongoing nature of the WATCH study allows comprehensive assessment of the real world clinical spectrum seen in a Specialist Asthma Centre and allows a longitudinal perspective of deeply phenotyped patients. It is anticipated that the WATCH cohort would act as a vehicle for potential collaborative asthma studies and will build upon our understanding of mechanisms underlying difficult asthma.

Electronic supplementary material

The online version of this article (10.1186/s12890-019-0862-2) contains supplementary material, which is available to authorized users.

Genetic associations of the response to inhaled corticosteroids in asthma: a systematic review

There is wide variability in the response to inhaled corticosteroids (ICS) in asthma. While some of this heterogeneity of response is due to adherence and environmental causes, genetic variation also influences response to treatment and genetic markers may help guide treatment. Over the past years, researchers have investigated the relationship between a large number of genetic variations and response to ICS by performing pharmacogenomic studies. In this systematic review we will provide a summary of recent pharmacogenomic studies on ICS and discuss the latest insight into the potential functional role of identified genetic variants. To date, seven genome wide association studies (GWAS) examining ICS response have been published. There is little overlap between identified variants and methodologies vary largely. However, in vitro and/or in silico analyses provide additional evidence that genes discovered in these GWAS (e.g. GLCCI1, FBXL7, T gene, ALLC, CMTR1) might play a direct or indirect role in asthma/treatment response pathways. Furthermore, more than 30 candidate-gene studies have been performed, mainly attempting to replicate variants discovered in GWAS or candidate genes likely involved in the corticosteroid drug pathway. Single nucleotide polymorphisms located in GLCCI1, NR3C1 and the 17q21 locus were positively replicated in independent populations. Although none of the genetic markers has currently reached clinical practise, these studies might provide novel insights in the complex pathways underlying corticosteroids response in asthmatic patients.

Characteristics of Adult Severe Refractory Asthma in Korea Analyzed From the Severe Asthma Registry

Purpose

Although mild to moderate asthma is much more common, the morbidity and mortality of severe asthma are much higher. This study was performed to identify and analyze the clinical characteristics of severe asthma in Korea.

Methods

We registered patients with severe refractory asthma into the Severe Asthma Registry supported by the Severe Asthma Work Group of the Korean Academy of Asthma, Allergy and Clinical Immunology. Patients were enrolled since 2010 from the 15 university hospitals nationwide in Korea. Severe asthma was defined according to modified European Respiratory Society/American Thoracic Society criteria. Information on demographics, medical history, pulmonary function tests and skin prick tests was collected; the clinical characteristics of severe asthmatics were analyzed from the collected data.

Results

A total of 489 patients were enrolled with a mean age of 62.3; 45% are male. Sixty percent of patients received Global Initiative for Asthma step 4 treatment, and 30% received step 5 treatment. The most common comorbidities were allergic rhinitis (58.7%). Aspirin hypersensitivity was observed in 14.0%. Approximately half (53.9%) are non-smokers. Atopy was proven in 38.5% of the patients. Regarding asthma medications, inhaled corticosteroids and long-acting β-agonist combination inhalers were most commonly prescribed (96.5%), followed by leukotriene antagonists (71.0%). A recombinant anti-immunoglobulin E monoclonal antibody (omalizumab) has been used in 1.8% of the patients. The mean forced vital capacity (FVC), forced expiratory volume in 1 second (FEV1) and FEV1/FVC were 78.7%, 67.5% and 67.9% of predicted values, respectively. The mean Asthma Control Test and quality of life questionnaire scores were 16.5 out of 25 and 59.5 out of 85, respectively.

Conclusions

The baseline characteristics of severe asthma patients in the Korea Severe Asthma Registry were analyzed and reported for the first time. With this cohort, further prospective studies should be performed to search for ways to improve management of severe refractory asthma.

Airway remodeling disease: primary human structural cells and phenotypic and pathway assays to identify targets with potential to prevent or reverse remodeling

Airway remodeling is a characteristic of many chronic respiratory diseases and occurs when there are significant changes to the architecture of the small and large airways leading to progressive loss of lung function. Some common features include airway smooth muscle and goblet cell hyperplasia, basement membrane thickening and subepithelial fibrosis. To explore the mechanisms driving airway remodeling and identify novel targets to treat this aspect of respiratory disease, appropriate models must be used that will accurately predict the pathology of disease. Phenotypic assays can be used in primary human lung cells to measure changes in cell behavior that are associated with particular disease pathology. This is becoming increasingly popular when targeting chronic pathologies such as airway remodeling, where phenotypic assays are likely to model disease in vitro more accurately than traditional second messenger assays. Here we review the use of primary human lung structural cells in a range of disease-relevant chronic phenotypic assays, and how they may be used in target identification/validation and drug discovery.

An algorithmic approach for the treatment of severe uncontrolled asthma

A small subgroup of patients with asthma suffers from severe disease that is either partially controlled or uncontrolled despite intensive, guideline-based treatment. These patients have significantly impaired quality of life and although they constitute <5% of all asthma patients, they are responsible for more than half of asthma-related healthcare costs. Here, we review a definition for severe asthma and present all therapeutic options currently available for these severe asthma patients. Moreover, we suggest a specific algorithmic treatment approach for the management of severe, difficult-to-treat asthma based on specific phenotype characteristics and biomarkers. The diagnosis and management of severe asthma requires specialised experience, time and effort to comprehend the needs and expectations of each individual patient and incorporate those as well as his/her specific phenotype characteristics into the management planning. Although some new treatment options are currently available for these patients, there is still a need for further research into severe asthma and yet more treatment options.

Stepwise approach for the treatment of severe asthmahttp://ow.ly/rLPl30i0TyZ

Perceptions of Severe Asthma and Asthma-COPD Overlap Syndrome Among Specialists: A Questionnaire Survey

Purpose

Severe asthma and asthma-chronic obstructive pulmonary disease (COPD) overlap syndrome (ACOS) are difficult to control and are often associated with poor clinical outcomes. However, much is not understood regarding the diagnosis and treatment of severe asthma and ACOS. To evaluate the current perceptions of severe asthma and COPD among asthma and COPD specialists, we designed an e-mail and internet-based questionnaire survey.

Methods

Subjects were selected based on clinical specialty from among the members of the Korean Academy of Asthma, Allergy and Clinical Immunology and the Korean Academy of Tuberculosis and Respiratory Diseases. Of 432 subjects who received an e-mail invitation to the survey, 95 subjects, including 58 allergists and 37 pulmonologists, responded and submitted their answers online.

Results

The specialists estimated that the percentage of severe cases among total asthma patients in their practice was 13.9%±11.0%. Asthma aggravation by stepping down treatment was the most common subtype, followed by frequent exacerbation, uncontrolled asthma despite higher treatment steps, and serious exacerbation. ACOS was estimated to account for 20.7% of asthma, 38.0% of severe asthma, and 30.1% of COPD cases. A history of smoking, persistently low forced expiratory volume in 1 second (FEV1), and low FEV1 variation were most frequently classified as the major criteria for the diagnosis of ACOS among asthma patients. Among COPD patients, the highly selected major criteria for ACOS were high FEV1 variation, positive bronchodilator response, a personal history of allergies and positive airway hyperresponsiveness. Allergists and pulmonologists showed different assessments and opinions on asthma phenotyping, percentage, and diagnostic criteria for ACOS.

Conclusions

Specialists had diverse perceptions and clinical practices regarding severe asthma and ACOS patients. This heterogeneity must be considered in future studies and strategy development for severe asthma and ACOS.

ST13 polymorphisms and their effect on exacerbations in steroid-treated asthmatic children and young adults

BACKGROUND

The clinical response to inhaled corticosteroids (ICS) is associated with single nucleotide polymorphisms (SNPs) in various genes. This study aimed to relate variations in genes in the steroid pathway and asthma susceptibility genes to exacerbations in children and young adults treated with ICS.

METHODS

We performed a meta-analysis of three cohort studies: Pharmacogenetics of Asthma Medication in Children: Medication with Anti-Inflammatory effects (n = 357, age: 4-12 years, the Netherlands), BREATHE (n = 820, age: 3-22 years, UK) and Paediatric Asthma Gene Environment Study (n = 391, age: 2-16 years, UK). Seventeen genes were selected based on a role in the glucocorticoid signalling pathway or a reported association with asthma. Two outcome parameters were used to reflect exacerbations: hospital visits and oral corticosteroid (OCS) use in the previous year. The most significant associations were tested in three independent validation cohorts; the Childhood Asthma Management Programme (clinical trial, n = 172, age: 5-12 years, USA), the Genes- environment and Mixture in Latino Americans II- study (n = 745, age: 8-21, USA) and the Pharmacogenetics of adrenal suppression cohort (n = 391, age: 5-18, UK) to test the robustness of the findings. Finally, all results were meta-analysed.

RESULTS

Two SNPs in ST13 (rs138335 and rs138337), but not in the other genes, were associated at a nominal level with an increased risk of exacerbations in asthmatics using ICS in the three cohorts studied. In a meta-analysis of all six studies, ST13 rs138335 remained associated with an increased risk of asthma-related hospital visits and OCS use in the previous year; OR = 1.22 (P = 0.013) and OR = 1.22 (P = 0.0017), respectively.

CONCLUSION AND CLINICAL RELEVANCE

A novel susceptibility gene, ST13, coding for a cochaperone of the glucocorticoid receptor, is associated with exacerbations in asthmatic children and young adults despite their ICS use. Genetic variation in the glucocorticoid signalling pathway may contribute to the interindividual variability in clinical response to ICS treatment in children and young adults.

Cost-Effectiveness of Bronchial Thermoplasty, Omalizumab, and Standard Therapy for Moderate-to-Severe Allergic Asthma

BACKGROUND

Bronchial thermoplasty (BT) is a recently developed treatment for patients with moderate-to-severe asthma. A few studies have suggested the clinical efficacy of this intervention. However, no study has evaluated the cost-effectiveness of BT compared to other alternative treatments for moderate-to-severe allergic asthma, which currently include omalizumab and standard therapy.

OBJECTIVE

To evaluate the cost-effectiveness of standard therapy, BT, and omalizumab for moderate-to-severe allergic asthma in the USA.

METHODS

A probabilistic Markov model with weekly cycles was developed to reflect the course of asthma progression over a 5-year time horizon. The study population was adults with moderate-to-severe allergic asthma whose asthma remained uncontrolled despite using high-dose inhaled corticosteroids (ICS, with or without long-acting beta-agonists [LABA]). A perspective of the health-care system was adopted with asthma-related costs as well as quality-adjusted life years (QALYs) and exacerbations as the outcomes.

RESULTS

For standard therapy, BT, and omalizumab, the discounted 5-year costs and QALYs were $15,400 and 3.08, $28,100 and 3.24, and $117,000 and 3.26, respectively. The incremental cost-effectiveness ratio (ICER) of BT versus standard therapy and omalizumab versus BT was $78,700/QALY and $3.86 million/QALY, respectively. At the willingness-to-pay (WTP) of $50,000/QALY and $100,000/QALY, the probability of BT being cost-effective was 9%, and 67%, respectively. The corresponding expected value of perfect information (EVPI) was $155 and $1,530 per individual at these thresholds. In sensitivity analyses, increasing the costs of BT from $14,900 to $30,000 increased its ICER relative to standard therapy to $178,000/QALY, and decreased the ICER of omalizumab relative to BT to $3.06 million/QALY. Reducing the costs of omalizumab by 25% decreased its ICER relative to BT by 29%.

CONCLUSIONS

Based on the available evidence, our study suggests that there is more than 60% chance that BT becomes cost-effective relative to omalizumab and standard therapy at the WTP of $100,000/QALY in patients with moderate-to-severe allergic asthma. However, there is a substantial uncertainty in the underlying evidence, indicating the need for future research towards reducing such uncertainty.

Lack of autophagy induces steroid-resistant airway inflammation

BACKGROUND

Neutrophilic corticosteroid-resistant asthma accounts for a significant proportion of asthma; however, little is known about the mechanisms that underlie the pathogenesis of the disease.

OBJECTIVE

We sought to address the role of autophagy in lung inflammation and the pathogenesis of corticosteroid-resistant neutrophilic asthma.

METHODS

We developed CD11c-specific autophagy-related gene 5 (Atg5)(-/-) mice and used several murine models to investigate the role of autophagy in asthmatic patients.

RESULTS

For the first time, we found that deletion of the Atg5 gene specifically in CD11c(+) cells, which leads to impairment of the autophagy pathway, causes unprovoked spontaneous airway hyperreactivity and severe neutrophilic lung inflammation in mice. We found that severe lung inflammation impairs the autophagy pathway, particularly in pulmonary CD11c(+) cells in wild-type mice. We further found that adoptive transfer of Atg5(-/-), but not wild-type, bone marrow-derived dendritic cells augments lung inflammation with increased IL-17A levels in the lungs. Our data indicate that neutrophilic asthma in Atg5(-/-) mice is glucocorticoid resistant and IL-17A dependent.

CONCLUSION

Our results suggest that lack of autophagy in pulmonary CD11c(+) cells induces neutrophilic airway inflammation and hyperreactivity.

Unrecognised psychopathology in patients with difficult asthma: major mental and personality disorders

BACKGROUND

Difficult asthma is a severe subgroup of asthma in which the main feature is uncontrollability of symptoms. Psychopathology is suggested to be prominent in patients with difficult asthma and considered important in its treatment; however, the evidence is scarce.

AIMS

To describe psychopathology in difficult asthma, both major mental and personality disorders, based on diagnostic interviews.

METHOD

This study was conducted in a specialised asthma care centre. A total of 51 patients with difficult asthma were diagnosed at the start of the treatment programme using two structured clinical interviews for both major mental (SCID-I) and personality disorders (SCID-II) according to DSM-IV-TR.

RESULTS

About 55% of the patients with difficult asthma had a psychiatric disorder of which 89% was undiagnosed and untreated before being interviewed. About 49% had a minimum of one major mental disorder of which the cluster of anxiety disorders was the most common cluster of major mental disorders, followed by somatoform disorders. About 20% were diagnosed with a personality disorder. Of the 10 patients with a personality disorder, 9 had an obsessive-compulsive personality disorder.

CONCLUSIONS

This study demonstrates that more than half of patients with difficult asthma had a psychiatric disorder of which 89% was unrecognised. This study highlights the importance of offering patients with difficult asthma a psychiatric diagnostic interview and/or a psychiatric consultation as part of their routine medical examination and provision of appropriate psychiatric treatment. Moreover, it highlights the urgency of further research into the role of psychopathology in the development of difficult asthma.

DECLARATION OF INTEREST

None.

COPYRIGHT AND USAGE

© The Royal College of Psychiatrists 2015. This is an open access article distributed under the terms of the Creative Commons Non-Commercial, No Derivatives (CC BY-NC-ND) licence.

Defining phenotypes in asthma: a step towards personalized medicine

Asthma is a common disease with a complex pathophysiology. It can present in various clinical forms and with different levels of severity. Unbiased cluster analytic methods have unravelled several phenotypes in cohorts representative of the whole spectrum of severity. Clusters of severe asthma include those on high-dose corticosteroid treatment, often with both inhaled and oral treatment, usually associated with severe airflow obstruction. Phenotypes with concordance between symptoms and sputum eosinophilia have been reported, including an eosinophilic inflammation-predominant group with few symptoms and late-onset disease who have a high prevalence of rhinosinusitis, aspirin sensitivity, and exacerbations. Sputum eosinophilia is also a biomarker that can predict therapeutic responses to antibody-based treatments to block the effects of the T-helper (Th)-2 cytokine, interleukin (IL)-5. Low Th2-expression has been predictive of poor therapeutic response to inhaled corticosteroid therapy. Current asthma schedules emphasise a step-up approach to treating asthma in relation to increasing severity, but, in more severe disease, phenotyping or endotyping of asthma will be necessary to determine new treatment strategies as severe asthma is recognized as being a particularly heterogeneous disease. Much less is known about 'non-eosinophilic' asthma. Phenotypic characterisation of corticosteroid insensitivity and chronic airflow obstruction of severe asthma is also needed. Phenotype-driven treatment of asthma will be further boosted by the advent of transcriptomic and proteomic technologies, with the application of systems biology or medicine approaches to defining phenotypes and biomarkers of disease and therapeutic response. This will pave the way towards personalized medicine and healthcare for asthma.

Oxidants induce a corticosteroid-insensitive phosphorylation of histone 3 at serine 10 in monocytes

Oxidative stress enhances inflammation and reduces the effectiveness of corticosteroids, but the inflammatory signalling pathways induced by oxidants remain ill-defined. Phosphorylation of histone 3 at serine 10 (H3-Pser10) marks out a subset of inflammatory genes for transcription, several of which are induced in oxidant-associated inflammation. However, the influence of oxidants or of corticosteroids on this modification remains unknown. We assessed the regulation of H3-Pser10 by oxidants and lipopolysaccharide (LPS) in human blood monocytes and lung macrophages and the effectiveness of its abolition in controlling inflammatory gene expression in cells from asthmatic subjects compared to corticosteroids alone. Both oxidants and LPS promoted the induction of H3-Pser10 which was unaffected by corticosteroids. The induction of H3-Pser10 was mediated through p38α mitogen-activated protein kinase (MAPK) and IκB kinase 2 (IKK-2) signalling. Consequently, inhibitors of p38α MAPK or IKK-2 used in combination with dexamethasone were more effective at controlling inflammatory gene expression from monocytes and lung macrophages from asthmatic patients than the corticosteroid alone. Therefore, reduction of H3-Pser10 by inhibition of p38α MAPK or of IKK-2 may provide greater anti-inflammatory control than corticosteroids alone in oxidant-associated inflammation such as severe asthma.

BET bromodomains regulate transforming growth factor-β-induced proliferation and cytokine release in asthmatic airway smooth muscle

Airway smooth muscle (ASM) mass is increased in asthma, and ASM cells from patients with asthma are hyperproliferative and release more IL-6 and CXCL8. The BET (bromo- and extra-terminal) family of proteins (Brd2, Brd3, and Brd4) govern the assembly of histone acetylation-dependent chromatin complexes. We have examined whether they modulate proliferation and cytokine expression in asthmatic ASM cells by studying the effect of BET bromodomain mimics JQ1/SGCBD01 and I-BET762. ASM cells from healthy individuals and nonsevere and severe asthmatics were pretreated with JQ1/SGCBD01 and I-BET762 prior to stimulation with FCS and TGF-β. Proliferation was measured by BrdU incorporation. IL-6 and CXCL8 release was measured by ELISA, and mRNA expression was measured by quantitative RT-PCR. ChIP using a specific anti-Brd4 antibody and PCR primers directed against the transcriptional start site of IL-6 and CXCL8 gene promoters was performed. Neither JQ1/SGCBD01 nor I-BET762 had any effect on ASM cell viability. JQ1/SGCBD01 and I-BET762 inhibited FCS+TGF-β-induced ASM cell proliferation and IL-6 and CXCL8 release in healthy individuals (≥ 30 nm) and in nonsevere and severe asthma patients (≥100 nm), with the latter requiring higher concentrations of these mimics. JQ1/SGCBD01 reduced Brd4 binding to IL8 and IL6 promoters induced by FCS+TGF-β. Mimics of BET bromodomains inhibit aberrant ASM cell proliferation and inflammation with lesser efficiency in those from asthmatic patients. They may be effective in reducing airway remodeling in asthma.

MicroRNA-146a and microRNA-146b expression and anti-inflammatory function in human airway smooth muscle

MicroRNA (miR)-146a and miR-146b are negative regulators of inflammatory gene expression in lung fibroblasts, epithelial cells, monocytes, and endothelial cells. The abundance of cyclooxygenase-2 (COX-2) and IL-1β is negatively regulated by the miR-146 family, suggesting miR-146a and/or miR-146b might modulate inflammatory mediator expression in airway smooth muscle thereby contributing to pathogenesis of asthma. To test this idea we compared miR-146a and miR-146b expression in human airway smooth muscle cells (hASMCs) from nonasthmatic and asthmatic subjects treated with cytomix (IL-1β, TNF-α, and IFNγ) and examined the miRNAs' effects on COX-2 and IL-1β expression. We found that cytomix treatment elevated miR-146a and miR-146b abundance. Induction with cytomix was greater than induction with individual cytokines, and asthmatic cells exhibited higher levels of miR-146a expression following cytomix treatment than nonasthmatic cells. Transfection of miR-146a or miR-146b mimics reduced COX-2 and IL-1β expression. A miR-146a inhibitor increased COX-2 and IL-1β expression, but a miR-146b inhibitor was ineffective. Repression of COX-2 and IL-1β expression by miR-146a correlated with reduced abundance of the RNA-binding protein human antigen R. These results demonstrate that miR-146a and miR-146b expression is inducible in hASMCs by proinflammatory cytokines and that miR-146a expression is greater in asthmatic cells. Both miR-146a and miR-146b can negatively regulate COX-2 and IL-1β expression at pharmacological levels, but loss-of-function studies showed that only miR-146a is an endogenous negative regulator in hASMCs. The results suggest miR-146 mimics may be an attractive candidate for further preclinical studies as an anti-inflammatory treatment of asthma.

Thiazolidinediones and the risk of asthma exacerbation among patients with diabetes: a cohort study

BACKGROUND

Thiazolidinediones are oral diabetes medications that selectively activate peroxisome proliferator-activated receptor gamma and have potent anti-inflammatory properties. While a few studies have found improvements in pulmonary function with exposure to thiazolidinediones, there are no studies of their impact on asthma exacerbations. Our objective was to assess whether exposure to thiazolidinediones was associated with a decreased risk of asthma exacerbation.

METHODS

We performed a cohort study of diabetic Veterans who had a diagnosis of asthma and were taking oral diabetes medications during the period of 10/1/2005 - 9/30/2006. The risk of asthma exacerbations and oral steroid use during 10/1/2006 - 9/30/2007 was compared between patients who were prescribed thiazolidinediones and patients who were on alternative oral diabetes medications. Multivariable logistic regression and negative binomial regression analyses were used to characterize this risk. A sensitivity analysis was performed, restricting our evaluation to patients who were adherent to diabetes therapy.

RESULTS

We identified 2,178 patients who were on thiazolidinediones and 10,700 who were not. Exposure to thiazolidinediones was associated with significant reductions in the risk of asthma exacerbation (OR = 0.79, 95% CI, 0.62 - 0.99) and oral steroid prescription (OR = 0.73, 95% CI 0.63 - 0.84). Among patients who were adherent to diabetes medications, there were more substantial reductions in the risks for asthma exacerbation (OR = 0.64, 95% CI 0.47 - 0.85) and oral steroid prescription (OR = 0.68, 95% CI 0.57 - 0.81).

CONCLUSIONS

Thiazolidinediones may provide a novel anti-inflammatory approach to asthma management by preventing exacerbations and decreasing the use of oral steroids.

Impaired macrophage phagocytosis of bacteria in severe asthma

Background

Bacteria are frequently cultured from sputum samples of severe asthma patients suggesting a defect in bacterial clearance from the airway. We measured the capacity of macrophages from patients with asthma to phagocytose bacteria.

Methods

Phagocytosis of fluorescently-labelled polystyrene beads, Haemophilus influenzae or Staphylococcus aureus by broncholaveolar lavage alveolar macrophages (AM) and by monocyte-derived macrophages (MDM) from non-asthmatics, mild-moderate and severe asthmatic patients was assessed using fluorimetry.

Results

There were no differences in phagocytosis of polystyrene beads by AMs or MDMs from any of the subject groups. There was reduced phagocytosis of Haemophilus influenzae and Staphylococcus aureus in MDMs from patients with severe asthma compared to non-severe asthma (p < 0.05 and p < 0.01, respectively) and healthy subjects (p < 0.01and p < 0.001, respectively). Phagocytosis of Haemophilus influenzae and Staphylococcus aureus by AM was also reduced in severe asthma compared to normal subjects (p < 0.05). Dexamethasone and formoterol did not suppress phagocytosis of bacteria by MDMs from any of the groups.

Conclusions

Persistence of bacteria in the lower airways may result partly from a reduced phagocytic capacity of macrophages for bacteria. This may contribute to increased exacerbations, airway colonization and persistence of inflammation.

Airway smooth muscle hyperproliferation is regulated by microRNA-221 in severe asthma

Increased airway smooth muscle (ASM) mass is a feature of asthmatic airways, and could result from augmented proliferation. We determined whether proliferation and IL-6 release are abnormal in ASM cells (ASMCs) from patients with severe asthma, and whether these features could be mediated by microRNA-221 and microRNA-222, through modulation of the cyclin-dependent kinase inhibitors, p21(WAF1) and p27(kip1). ASMCs cultured from bronchial biopsies of healthy subjects and patients with nonsevere or severe asthma were studied. Proliferation was measured by the incorporation of bromodeoxyuridine and IL-6 by ELISA. FCS and transforming growth factor (TGF)-β caused greater proliferation and IL-6 release in patients with severe compared with nonsevere asthma and normal subjects. FCS + TGF-β inhibited p21(WAF1) and p27(kip1) expression, and increased microRNA-221 (miR-221) expression in ASMCs from individuals with severe asthma. miR-221, and not miR-222, mimics the increased proliferation and IL-6 release induced by FCS + TGF in healthy ASM, whereas in patients with severe asthma, the inhibition of miR-221, but not miR-222, inhibited proliferation and IL-6 release. miR-221 inhibition led to the increased expression of FCS + TGF-β-induced p21(WAF1) and p27(kip1). Dexamethasone suppressed proliferation in healthy subjects, but not in subjects with asthma. IL-6 was less suppressible by dexamethasone in patients with nonsevere and severe asthma, compared with healthy subjects. miR-221 did not influence the effects of dexamethasone. ASM from patients with severe asthma shows greater proliferation and IL-6 release than in patients with nonsevere asthma, but both groups show corticosteroid insensitivity. miR-221 regulates p21(WAF1) and p27(kip1) expression levels. Furthermore, miR-221 regulates the hyperproliferation and IL-6 release of ASMCs from patients with severe asthma, but does not regulate corticosteroid insensitivity.

Development of a novel severe triple allergen asthma model in mice which is resistant to dexamethasone and partially resistant to TLR7 and TLR9 agonist treatment

Severe asthma is characterised by persistent inflammation, hyperreactivity and remodeling of the airways. No efficient treatment is available, this is particularly the case for steroid resistant phenotypes. Our aim therefore was to develop a preclinical model showing characteristics of severe human asthma including steroid insensitivity. Mice were first sensitized with ovalbumin, extracts of cockroach or house dust mite followed by a challenge period of seven weeks. Further to this, an additional group of mice was sensitized with all three allergens and then challenged with allergen alternating weekly between allergens. All three allergens applied separately to the mice induced comparably strong Th2-type airway inflammation, airway hyperreactivity and airway remodeling, which was characterised by fibrosis and increased smooth muscle thickness. In contrast, application of all three allergens together resulted in a greater Th2 response and increased airway hyperreactivity and a stronger albeit not significant remodeling phenotype compared to using HDM or CRA. In this triple allergen model dexamethasone application, during the last 4 weeks of challenge, showed no suppressive effects on any of these parameters in this model. In contrast, both TLR7 agonist resiquimod and TLR9 agonist CpG-ODN reduced allergen-specific IgE, eosinophils, and collagen I in the lungs. The TLR9 agonist also reduced IL-4 and IL-5 whilst increasing IFN-γ and strongly IL-10 levels in the lungs, effects not seen with the TLR7 agonist. However, neither TLR agonist had any effect on airway hyperreactivity and airway smooth muscle mass. In conclusion we have developed a severe asthma model, which is steroid resistant and only partially sensitive to TLR7 and TLR9 agonist treatment. This model may be particular useful to test new potential therapeutics aiming at treating steroid resistant asthma in humans and investigating the underlying mechanisms responsible for steroid insensitivity.

Dual oxidase regulates neutrophil recruitment in allergic airways

Enhanced reactive oxygen species production in allergic airways is well described and correlates with increased airway contractions, inflammatory cell infiltration, goblet cell metaplasia, and mucus hypersecretion. There is also an abundance of interleukin-4/interleukin-13 (IL-4/IL-13)- or interleukin-5-secreting cells that are thought to be central to the pathogenesis of allergic asthma. We postulated that the dual oxidases (DUOX1 and DUOX2), members of the nicotinamide adenine dinucleotide phosphate oxidase family that release hydrogen peroxide (H2O2) in the respiratory tract, are critical proteins in the pathogenesis of allergic airways. DUOX activity is regulated by cytokines, including IL-4 and IL-13, and DUOX-mediated H2O2 influences several important features of allergic asthma: mucin production, IL-8 secretion, and wound healing. The objective of this study was to establish the contribution of DUOXs to the development of allergic asthma in a murine model. To accomplish this goal, we utilized a DUOXA-deficient mouse model (Duoxa(-/-)) that lacked maturation factors for both DUOX1 and DUOX2. Our results are the first to demonstrate evidence of DUOX protein and DUOX functional activity in murine airway epithelium. We also demonstrate that DUOXA maturation factors are required for airway-specific H2O2 production and localization of DUOX to cilia of fully differentiated airway epithelial cells. We compared wild-type and Duoxa(-/-) mice in an ovalbumin exposure model to determine the role of DUOX in allergic asthma. In comparison to DUOX-intact mice, Duoxa(-/-) mice had reduced mucous cell metaplasia and lower levels of TH2 cytokine levels in bronchoalveolar fluid. In addition, increased airway resistance in response to methacholine was observed in Duoxa(+/+) mice, as expected, but was absent in Duoxa(-/-) mice. Surprisingly, Duoxa(-/-) mice had decreased influx of neutrophils in bronchoalveolar fluid and lung tissue sections associated with a lower level of the chemotactic cytokine IL-6. These findings suggest that DUOX-derived H2O2 has an important role in signaling neutrophils into allergic airways.

How variability in clinical phenotypes should guide research into disease mechanisms in asthma

Asthma is increasingly being considered as a collection of different phenotypes that present with intermittent wheezing. Unbiased approaches to classifying asthma have led to the identification of distinct phenotypes based on age of onset of disease, atopic state, disease severity or activity, degree of chronic airflow obstruction, and sputum eosinophilia. Linking phenotypes to known disease mechanism is likely to be more fruitful in determining the potential targets necessary for successful therapies of specific endotypes. A "Th2-high expression" signature from the epithelium of patients with asthma identifies a subset of patients with high eosinophilia and good therapeutic responsiveness to corticosteroids. Other characteristic traits of asthma include noneosinophilic asthma, corticosteroid insensitivity, obesity-associated, and exacerbation-prone. Further progress into asthma mechanisms will be driven by unbiased data integration of multiscale data sets from omics technologies with those phenotypic characteristics and by using mathematical modeling. This will lead to the discovery of new pathways and their integration into endotypes and also set up further hypothesis-driven research. Continued iteration through experimentation or modeling will be needed to refine the phenotypes that relate to outcomes and also delineate specific treatments for specific phenotypes.

The role of rhinosinusitis in severe asthma

The prevalence of asthma is approximately 5% to 10% in the general population. Of these, approximately 5% to 10% are severe asthmatics who respond poorly to asthmatic drugs, including high-dose inhaled steroids. Severe asthmatics have persistent symptoms, frequent symptom exacerbation, and severe airway obstruction even when taking high-dose inhaled steroids. The medical costs of treating severe asthmatics represent ~50% of the total healthcare costs for asthma. Risk factors for severe asthma are genetic and environmental, including many kinds of aeroallergens, β-blockers, and anti-inflammatory drugs. Gastroesophageal reflux disease and factors such as denial, anxiety, fear, depression, socioeconomic status, and alcohol consumption can exacerbate asthma. Rhinitis and asthma usually occur together. There is increasing evidence that allergic rhinitis and rhinosinusitis may influence the clinical course of asthma. This review discusses the role of rhinosinusitis in severe asthma.

Inhaled and systemic corticosteroid response in severe asthma assessed by alveolar nitric oxide: a randomized crossover pilot study of add-on therapy

AIMS

Alveolar nitric oxide (CA(NO)) is a potential biomarker of small airway inflammation. We investigated effects on CA(NO) of the addition of coarse and fine particle inhaled corticosteroids to standard therapy in severe asthma.

METHODS

Severe asthmatics taking ≥1600 µg day(-1) budesonide or equivalent performed a randomized open-label crossover study. Subjects with FEV(1) < 80%, gas trapping and CA(NO) ≥2 ppb entered a 6 week dose-ramp run-in of fluticasone/salmeterol(FPSM) 250/50 µg twice daily for 3 weeks, then 500/50 µg twice daily for 3 weeks. Patients then received additional HFA-beclomethasone diproprionate (BDP) 200 µg twice daily or FP 250 µg twice daily for 3 weeks in a crossover. Participants then received prednisolone(PRED) 25 mg day(-1) for 1 week. Nitric oxide, lung function, mannitol challenge, systemic inflammatory markers and urinary cortisol were measured.

RESULTS

Fifteen completed per protocol: mean (SD) age 51 (12) years, FEV(1) 58 (13)% predicted, residual volume 193 (100)% predicted and mannitol(PD10) 177 (2.8) µg. There was no significant difference between FPSM and add-on therapy for CA(NO). FPSM/BDP and FPSM/PRED suppressed broncial flux (Jaw(NO)) and FE(NO) compared with FPSM alone, but there was no significant difference between FPSM/BDP and FPSM/FP. ECP, e-selectin and ICAM-1 were suppressed by FPSM/PRED compared with FPSM and FPSM/FP but not FPSM/BDP. Plasma cortisol was significantly suppressed by FPSM/PRED.

CONCLUSION

In severe asthma, CA(NO) is insensitive to changes in dose and delivery of inhaled corticosteroids and is not suppressed by systemic corticosteroids. Additional inhaled HFA-BDP reduced FE(NO) and Jaw(NO) without adrenal suppression. There was a trend to reduction in FE(NO) and Jaw(NO) with additional FP but this did not reach statistical significance. PRED reduced FE(NO) and Jaw(NO) with suppression of systemic inflammatory markers and urinary cortisol.

Correlation between fungal sIgE and bronchial asthma severity

Fungal sensitisation is closely associated with asthma; however, the correlation between fungi and asthma severity remains unclear. The aim of this study was to investigate the severity of asthma in 100 patients with asthma due to fungal and non-fungal allergens. A total of 100 outpatients and inpatients with asthma were selected from 2010 to 2011 and were divided into three groups (mild, moderate and severe) according to their clinical manifestations, lung function results and treatment situations. Enzyme-linked immunosorbent assay (ELISA) was used to detect the levels of specific immunoglobulin E (sIgE) to five fungal allergens and seven non-fungal allergens in the serum of all patients. The levels of sIgE to Aspergillus, Penicillium and Candida albicans allergens in the severe group were significantly higher compared with those in the moderate and mild groups (P<0.001 and P<0.05, respectively); those of the moderate group were significantly higher compared with those of the mild group (P<0.05). No significant difference was observed for the levels of sIgE to Alternaria alternata among the three groups. sIgE to Cladosporium herbarum was not present for all three groups. No significant difference was observed for the levels of sIgE to non-fungal allergens among the three groups. Fungal allergens are closely correlated with the severity of asthma, whereas non-fungal allergens are not.

Severe asthma: an expanding and mounting clinical challenge

Although all patients with asthma have variable airflow obstruction, airway inflammation, and bronchial hyperresponsiveness, some have disease that is severe in many aspects: persistent airflow obstruction, ongoing symptoms, increased frequency of exacerbations, and, most importantly, a diminished response to medications. A number of definitions have emerged to characterize the clinical features of severe asthma, but a central feature of this phenotype is the need for high doses of medications, especially corticosteroids, in attempts to achieve disease control. The prevalence of severe asthma is also undergoing reevaluation from the usual estimate of 10% to larger numbers on the basis of medication needs and the lack of disease control achieved. At present, the underlying mechanisms of severe asthma are not established but likely reflect a heterogeneous pattern, rather than a single unifying process. Guideline-directed treatment for severe asthma has limits with usual approaches centered on high doses of inhaled corticosteroids, long-acting β-agonists, and trials with omalizumab, the monoclonal antibody to IgE. With the development of approaches to recognize asthma phenotypes with distinct pathogenesis and hence unique therapeutic targets, it is hoped that a personalized strategy in treatment directed toward disease-specific features will improve outcomes for this high-risk, severely affected population of patients.

Childhood asthma: diagnosis and treatment

Many children suffer from recurrent coughing, wheezing and chest tightness. In preschool children one third of all children have these symptoms before the age of six, but only 40% of these wheezing preschoolers will continue to have asthma. In older school-aged children the majority of the children have asthma. Quality of life is affected by asthma control. Sleep disruption and exercised induced airflow limitation have a negative impact on participation in sports and social activities, and may influence family life. The goal of asthma therapy is to achieve asthma control, but only a limited number of patients are able to reach total control. This may be due to an incorrect diagnosis, co-morbidities or poor inhalation technique, but in the majority of cases non-adherence is the main reason for therapy failures. However, partnership with the parents and the child is important in order to set individually chosen goals of therapy and may be of help to improve control. Non-pharmacological measures aim at avoiding tobacco smoke, and when a child is sensitised, to avoid allergens. In pharmacological management international guidelines such as the GINA guideline and the British Guideline on the Management of Asthma are leading.

Enterococcus faecalis overcomes foreign body-mediated inflammation to establish urinary tract infections

Urinary catheterization elicits major histological and immunological changes that render the bladder susceptible to microbial invasion, colonization, and dissemination. However, it is not understood how catheters induce these changes, how these changes act to promote infection, or whether they may have any protective benefit. In the present study, we examined how catheter-associated inflammation impacts infection by Enterococcus faecalis, a leading cause of catheter-associated urinary tract infection (CAUTI), a source of significant societal and clinical challenges. Using a recently optimized murine model of foreign body-associated UTI, we found that the implanted catheter itself was the primary inducer of inflammation. In the absence of the silicone tubing implant, E. faecalis induced only minimal inflammation and was rapidly cleared from the bladder. The catheter-induced inflammation was only minimally altered by subsequent enterococcal infection and was not suppressed by inhibitors of the neurogenic pathway and only partially by dexamethasone. Despite the robust inflammatory response induced by urinary implantation, E. faecalis produced biofilm and high bladder titers in these animals. Induction of inflammation in the absence of an implanted catheter failed to promote infection, suggesting that the presence of the catheter itself is essential for E. faecalis persistence in the bladder. Immunosuppression prior to urinary catheterization enhanced E. faecalis colonization, suggesting that implant-mediated inflammation contributes to the control of enterococcal infection. Thus, this study underscores the need for novel strategies against CAUTIs that seek to reduce the deleterious effects of implant-mediated inflammation on bladder homeostasis while maintaining an active immune response that effectively limits bacterial invaders.

Restoration of corticosteroid sensitivity by p38 mitogen activated protein kinase inhibition in peripheral blood mononuclear cells from severe asthma

BACKGROUND

Severe asthma accounts for a small number of asthmatics but represents a disproportionate cost to health care systems. The underlying mechanism in severe asthma remains unknown but several mechanisms are likely to be involved because of a very heterogeneous profile. We investigated the effects of a p38MAPK inhibitor in corticosteroid sensitivity in peripheral blood mononuclear cells (PBMCs) from severe asthmatics and the profile of its responders.

METHODOLOGY/PRINCIPAL FINDINGS

Corticosteroid sensitivity was determined by measuring dexamethasone inhibition of CD3/28 and TNF-α induced IL-8 production in PBMCs by using ELISA. PBMCs from severe asthmatics were relatively less sensitive to dexamethasone (Dex) as compared to those of non-severe asthmatics and healthy volunteers. The IC(50) values of Dex negatively correlated with decreased glucocorticoid receptor (GR) nuclear translocation assessed using immunocytochemistry (r = -0.65; p<0.0005) and with decreased FEV(1) (% predicted) (r = 0.6; p<0.0005). A p38α/β inhibitor (SB203580) restored Dex-sensitivity in a subpopulation of severe asthma that was characterized by a defective GR nuclear translocation, clinically by lower FEV(1) and higher use of oral prednisolone. We also found that SB203580 partially inhibited GR phosphorylation at serine 226, resulting in increased GR nuclear translocation in IL-2/IL-4 treated corticosteroid insensitive U937s.

CONCLUSIONS/SIGNIFICANCE

p38MAPKα/β is involved in defective GR nuclear translocation due to phosphorylation at Ser226 and this will be a useful biomarker to identify responders to p38MAPKα/β inhibitor in the future.

Steroid response in refractory asthmatics

Inhaled glucocorticosteroids are currently the most effective anti-inflammatory controller medications for treating persistent asthma. The efficacies of glucocorticoids include reducing asthma symptoms, reducing exacerbation frequency, improving quality of life, improving lung function, decreasing airway hyperresponsiveness, controlling airway inflammation, and reducing mortality. However, the treatment response to glucocorticosteroids in asthmatics varies, and certain subtypes of asthma, such as refractory asthma, respond poorly to high-dose inhaled glucocorticoid and systemic steroids. The medical costs of treating refractory asthmatics represent about 50% of the total healthcare cost for asthma. A thorough understanding of the mechanisms of glucocorticoid action, patient responses to glucocorticoids, and steroid resistance observed in refractory asthmatics is necessary for the targeted development of therapeutic drugs. This review discusses the characteristics of severe refractory asthmatics and the mechanisms of steroid response and resistance in asthma treatment.

Bacteria in sputum of stable severe asthma and increased airway wall thickness

BACKGROUND

Patients with chronic asthma have thicker intrapulmonary airways measured on high resolution computed tomography (HRCT). We determined whether the presence of lower airway bacteria was associated with increased airway wall thickness.

METHODS

In 56 patients with stable severe asthma, sputum specimens obtained either spontaneously or after induction with hypertonic saline were cultured for bacteria and thoracic HRCT scans obtained. Wall thickness (WT) and area (WA) expressed as a ratio of airway diameter (D) and total area, respectively, were measured at five levels.

RESULTS

Positive bacterial cultures were obtained in 29 patients, with H. influenzae, P. aeruginosa and S. aureus being the commonest strains. Logistic regression analysis showed that this was associated with the duration of asthma and the exacerbations during the past year. In airways > 2 mm, there was no significant difference in WA (67.5 ± 5.4 vs 66.4 ± 5.4) and WT/D (21.6 ± 2.7 vs 21.3 ± 2.4) between the culture negative versus positive groups. Similarly, in airways (≤ 2 mm), there were no significant differences in these parameters. The ratio of √wall area to Pi was negatively correlated with FEV1% predicted (p < 0.05).

CONCLUSIONS

Bacterial colonization of the lower airways is common in patients with chronic severe asthma and is linked to the duration of asthma and having had exacerbations in the past year, but not with an increase in airway wall thickness.

Relationship between serum vitamin D, disease severity, and airway remodeling in children with asthma

RATIONALE

Little is known about vitamin D status and its effect on asthma pathophysiology in children with severe, therapy-resistant asthma (STRA).

OBJECTIVES

Relationships between serum vitamin D, lung function, and pathology were investigated in pediatric STRA.

METHODS

Serum 25-hydroxyvitamin D [25(OH)D(3)] was measured in 86 children (mean age, 11.7 yr): 36 with STRA, 26 with moderate asthma (MA), and 24 without asthma (control subjects). Relationships between 25(OH)D(3), the asthma control test (ACT), spirometry, corticosteroid use, and exacerbations were assessed. Twenty-two of 36 children with STRA underwent fiberoptic bronchoscopy, bronchoalveolar lavage, and endobronchial biopsy with assessment of airway inflammation and remodeling.

MEASUREMENTS AND MAIN RESULTS

25(OH)D(3) levels (median [IQR]) were significantly lower in STRA (28 [22-38] nmol/L) than in MA (42.5 [29-63] nmol/L) and control subjects (56.5 [45-67] nmol/L) (P < 0.001). There was a positive relationship between 25(OH)D(3) levels and percent predicted FEV(1) (r = 0.4, P < 0.001) and FVC (r = 0.3, P = 0.002) in all subjects. 25(OH)D(3) levels were positively associated with ACT (r = 0.6, P < 0.001), and inversely associated with exacerbations (r = -0.6, P < 0.001) and inhaled steroid dose (r = -0.39, P = 0.001) in MA and STRA. Airway smooth muscle (ASM) mass, but not epithelial shedding or reticular basement membrane thickness, was inversely related to 25(OH)D(3) levels (r = -0.6, P = 0.008). There was a positive correlation between ASM mass and bronchodilator reversibility (r = 0.6, P = 0.009) and an inverse correlation between ASM mass and ACT (r = -0.7, P < 0.001).

CONCLUSIONS

Lower vitamin D levels in children with STRA were associated with increased ASM mass and worse asthma control and lung function. The link between vitamin D, airway structure, and function suggests vitamin D supplementation may be useful in pediatric STRA.

Immunoglobulin E receptor signaling and asthma

Elevated IgE levels and increased IgE sensitization to allergens are central features of allergic asthma. IgE binds to the high-affinity Fcε receptor I (FcεRI) on mast cells, basophils, and dendritic cells and mediates the activation of these cells upon antigen-induced cross-linking of IgE-bound FcεRI. FcεRI activation proceeds through a network of signaling molecules and adaptor proteins and is negatively regulated by a number of cell surface and intracellular proteins. Therapeutic neutralization of serum IgE in moderate-to-severe allergic asthmatics reduces the frequency of asthma exacerbations through a reduction in cell surface FcεRI expression that results in decreased FcεRI activation, leading to improved asthma control. Our increasing understanding of IgE receptor signaling may lead to the development of novel therapeutics for the treatment of asthma.

Combination of lung ultrasound (a comet-tail sign) and N-terminal pro-brain natriuretic peptide in differentiating acute heart failure from chronic obstructive pulmonary disease and asthma as cause of acute dyspnea in prehospital emergency setting

Introduction

We studied the diagnostic accuracy of bedside lung ultrasound (the presence of a comet-tail sign), N-terminal pro-brain natriuretic peptide (NT-proBNP) and clinical assessment (according to the modified Boston criteria) in differentiating heart failure (HF)-related acute dyspnea from pulmonary (chronic obstructive pulmonary disease (COPD)/asthma)-related acute dyspnea in the prehospital setting.

Methods

Our prospective study was performed at the Center for Emergency Medicine, Maribor, Slovenia, between July 2007 and April 2010. Two groups of patients were compared: a HF-related acute dyspnea group (n = 129) and a pulmonary (asthma/COPD)-related acute dyspnea group (n = 89). All patients underwent lung ultrasound examinations, along with basic laboratory testing, rapid NT-proBNP testing and chest X-rays.

Results

The ultrasound comet-tail sign has 100% sensitivity, 95% specificity, 100% negative predictive value (NPV) and 96% positive predictive value (PPV) for the diagnosis of HF. NT-proBNP (cutoff point 1,000 pg/mL) has 92% sensitivity, 89% specificity, 86% NPV and 90% PPV. The Boston modified criteria have 85% sensitivity, 86% specificity, 80% NPV and 90% PPV. In comparing the three methods, we found significant differences between ultrasound sign and (1) NT-proBNP (P < 0.05) and (2) Boston modified criteria (P < 0.05). The combination of ultrasound sign and NT-proBNP has 100% sensitivity, 100% specificity, 100% NPV and 100% PPV. With the use of ultrasound, we can exclude HF in patients with pulmonary-related dyspnea who have positive NT-proBNP (> 1,000 pg/mL) and a history of HF.

Conclusions

An ultrasound comet-tail sign alone or in combination with NT-proBNP has high diagnostic accuracy in differentiating acute HF-related from COPD/asthma-related causes of acute dyspnea in the prehospital emergency setting.

Trial registration

ClinicalTrials.gov NCT01235182.

Molecular mechanism of glucocorticoid resistance in inflammatory bowel disease

Natural and synthetic glucocorticoids (GCs) are widely employed in a number of inflammatory, autoimmune and neoplastic diseases, and, despite the introduction of novel therapies, remain the first-line treatment for inducing remission in moderate to severe active Crohn’s disease and ulcerative colitis. Despite their extensive therapeutic use and the proven effectiveness, considerable clinical evidence of wide inter-individual differences in GC efficacy among patients has been reported, in particular when these agents are used in inflammatory diseases. In recent years, a detailed knowledge of the GC mechanism of action and of the genetic variants affecting GC activity at the molecular level has arisen from several studies. GCs interact with their cytoplasmic receptor, and are able to repress inflammatory gene expression through several distinct mechanisms. The glucocorticoid receptor (GR) is therefore crucial for the effects of these agents: mutations in the GR gene (NR3C1, nuclear receptor subfamily 3, group C, member 1) are the primary cause of a rare, inherited form of GC resistance; in addition, several polymorphisms of this gene have been described and associated with GC response and toxicity. However, the GR is not self-standing in the cell and the receptor-mediated functions are the result of a complex interplay of GR and many other cellular partners. The latter comprise several chaperonins of the large cooperative hetero-oligomeric complex that binds the hormone-free GR in the cytosol, and several factors involved in the transcriptional machinery and chromatin remodeling, that are critical for the hormonal control of target genes transcription in the nucleus. Furthermore, variants in the principal effectors of GCs (e.g. cytokines and their regulators) have also to be taken into account for a comprehensive evaluation of the variability in GC response. Polymorphisms in genes involved in the transport and/or metabolism of these hormones have also been suggested as other possible candidates of interest that could play a role in the observed inter-individual differences in efficacy and toxicity. The best-characterized example is the drug efflux pump P-glycoprotein, a membrane transporter that extrudes GCs from cells, thereby lowering their intracellular concentration. This protein is encoded by the ABCB1/MDR1 gene; this gene presents different known polymorphic sites that can influence its expression and function. This editorial reviews the current knowledge on this topic and underlines the role of genetics in predicting GC clinical response. The ambitious goal of pharmacogenomic studies is to adapt therapies to a patient’s specific genetic background, thus improving on efficacy and safety rates.

Multi-symptom asthma is closely related to nasal blockage, rhinorrhea and symptoms of chronic rhinosinusitis-evidence from the West Sweden Asthma Study

Background

We have previously shown that approximately 25% of those with asthma in West Sweden have multiple asthma symptoms, which may describe a group of patients with more severe disease. Furthermore, asthma is associated with several co-morbid diseases, including rhinitis and chronic rhinosinusitis. The aim of this study was to determine whether multi-symptom asthma is related to signs of severe asthma, and to investigate the association between multi-symptom asthma and different symptoms of allergic and chronic rhinosinusitis.

Methods

This study analyzed data on asthma symptoms, rhinitis, and chronic rhinosinusitis from the 2008 West Sweden Asthma Study, which is an epidemiologically based study using the OLIN and GA²LEN respiratory and allergy focused questionnaires.

Results

Multi-symptom asthma was present in 2.1% of the general population. Subjects with multi-symptom asthma had more than double the risk of having night-time awakenings caused by asthma compared with those with fewer asthma symptoms (P < 0.001). The prevalence of allergic rhinitis was similar in the fewer- and multi-symptom asthma groups, but nasal blockage and rhinorrhea were significantly increased in those with multi- versus fewer-symptom asthma (odds ratio 2.21; 95% confidence interval 1.64-2.97, versus 1.49; 1.10-2.02, respectively). Having any, or one to four symptoms of chronic rhinosinusitis significantly increased the risk of having multi- versus fewer-symptom asthma (P < 0.01).

Conclusion

An epidemiologically identified group of individuals with multiple asthma symptoms harbour to greater extent those with signs of severe asthma. The degree of rhinitis, described by the presence of symptoms of nasal blockage or rhinorrhea, as well as the presence of any or several signs of chronic rhinosinusitis, significantly increases the risk of having multi-symptom asthma.

Recommendation for optimal management of severe refractory asthma

Patients whose asthma is not adequately controlled despite treatment with a combination of high dose inhaled corticosteroids and long-acting bronchodilators pose a major clinical challenge and an important health care problem. Patients with severe refractory disease often require regular oral corticosteroid use with an increased risk of steroid-related adverse events. Alternatively, immunomodulatory and biologic therapies may be considered, but they show wide variation in efficacy across studies thus limiting their generalizability. Managing asthma that is refractory to standard treatment requires a systematic approach to evaluate adherence, ensure a correct diagnosis, and identify coexisting disorders and trigger factors. In future, phenotyping of patients with severe refractory asthma will also become an important element of this systematic approach, because it could be of help in guiding and tailoring treatments. Here, we propose a pragmatic management approach in diagnosing and treating this challenging subset of asthmatic patients.

Testing bias in clinical databases: methodological considerations

Background

Laboratory testing in clinical practice is never a random process. In this study we evaluated testing bias for neutrophil counts in clinical practice by using results from requested and non-requested hematological blood tests.

Methods

This study was conducted using data from the Utrecht Patient Oriented Database. This clinical database is unique, as it contains physician requested data, but also data that are not requested by the physician, but measured as result of requesting other hematological parameters. We identified adult patients, hospitalized in 2005 with at least two blood tests during admission, where requests for general blood profiles and specifically for neutrophil counts were contrasted in scenario analyses. Possible effect modifiers were diagnosis and glucocorticoid use.

Results

A total of 567 patients with requested neutrophil counts and 1,439 patients with non-requested neutrophil counts were analyzed. The absolute neutrophil count at admission differed with a mean of 7.4 × 10⁹/l for requested counts and 8.3 × 10⁹/l for non-requested counts (p-value < 0.001). This difference could be explained for 83.2% by the occurrence of cardiovascular disease as underlying disease and for 4.5% by glucocorticoid use.

Conclusion

Requests for neutrophil counts in clinical databases are associated with underlying disease and with cardiovascular disease in particular. The results from our study show the importance of evaluating testing bias in epidemiological studies obtaining data from clinical databases.

Bone marrow stromal cells use TGF-beta to suppress allergic responses in a mouse model of ragweed-induced asthma

Bone marrow stromal cells [BMSCs; also known as mesenchymal stem cells (MSCs)] effectively suppress inflammatory responses in acute graft-versus-host disease in humans and in a number of disease models in mice. Many of the studies concluded that BMSC-driven immunomodulation is mediated by the suppression of proinflammatory Th1 responses while rebalancing the Th1/Th2 ratio toward Th2. In this study, using a ragweed induced mouse asthma model, we studied if BMSCs could be beneficial in an allergic, Th2-dominant environment. When BMSCs were injected i.v. at the time of the antigen challenge, they protected the animals from the majority of asthma-specific pathological changes, including inhibition of eosinophil infiltration and excess mucus production in the lung, decreased levels of Th2 cytokines (IL-4, IL-5, and IL-13) in bronchial lavage, and lowered serum levels of Th2 immunoglobulins (IgG1 and IgE). To explore the mechanism of the effect we used BMSCs isolated from a variety of knockout mice, performed in vivo blocking of cytokines and studied the effect of asthmatic serum and bronchoalveolar lavage from ragweed challenged animals on the BMSCs in vitro. Our results suggest that IL-4 and/or IL-13 activate the STAT6 pathway in the BMSCs resulting in an increase of their TGF-beta production, which seems to mediate the beneficial effect, either alone, or together with regulatory T cells, some of which might be recruited by the BMSCs. These data suggest that, in addition to focusing on graft-versus-host disease and autoimmune diseases, allergic conditions--specifically therapy resistant asthma--might also be a likely target of the recently discovered cellular therapy approach using BMSCs.