Predictive value of blood eosinophils and exhaled nitric oxide in adults with mild asthma: a prespecified subgroup analysis of an open-label, parallel-group, randomised controlled trial

Evidence for 2 clusters among patients with noneosinophilic asthma

BACKGROUND

Although asthma is often seen as an eosinophilic disease associated with atopy, patients with noneosinophilic asthma represent a substantial part of the population with asthma.

OBJECTIVE

To apply an unsupervised clustering method in a cohort of 588 patients with noneosinophilic asthma (sputum eosinophils < 3%) recruited from an asthma clinic of a secondary care center.

METHODS

Our cluster analysis of the whole cohort identified 2 subgroups as cluster 1 (n = 417) and cluster 2 (n = 171).

RESULTS

Cluster 1 comprised a predominantly female group with late disease onset, a low proportion of atopy (24%), and a substantial smoking history (53%). In this cluster, treatment burden was low (<50% of inhaled corticosteroid users); asthma control and quality of life were poor, with median Asthma Control Test, Asthma Control Questionnaire, and Asthma Quality of Life scores of 16, 1.7, and 4.5, respectively, whereas lung function was preserved with a median postbronchodilation forced expiratory volume in 1 second of 93% predicted. Cluster 2 was a predominantly male group, almost exclusively comprising patients with atopy (99%) with early disease onset and a moderate treatment burden (median inhaled corticosteroids dose 800 µg/d equivalent beclomethasone). In cluster 2, asthma was partially controlled, with median Asthma Control Test and Asthma Control Questionnaire scores reaching 18 and 1.3, respectively, and lung function well preserved with a median postbronchodilation of 95% predicted. Although systemic and airway neutrophilic inflammation was the dominant pattern in cluster 1, cluster 2 essentially comprised paucigranulocytic asthma with moderately elevated fraction exhaled nitric oxide.

CONCLUSION

Noneosinophilic asthma splits into 2 clusters distinguishing by disease onset, atopic status, smoking history, systemic and airway inflammation, and disease control and quality of life.

The carbon footprint of as-needed budesonide/formoterol in mild asthma: a post hoc analysis

INTRODUCTION

The use of pressurised metered-dose inhalers (pMDIs) and asthma exacerbations necessitating healthcare reviews contribute substantially to the global carbon footprint of healthcare. It is possible that a reduction in carbon footprint could be achieved by switching patients with mild asthma from salbutamol pMDI reliever-based therapy to inhaled corticosteroid-formoterol dry powder inhaler (DPI) reliever therapy, as recommended by the Global Initiative for Asthma.

METHODS

This post hoc analysis included all 668 adult participants in the Novel START trial, who were randomised 1:1:1 to treatment with as-needed budesonide/formoterol DPI, as-needed salbutamol pMDI or maintenance budesonide DPI plus as-needed salbutamol pMDI. The primary outcome was carbon footprint of asthma management, expressed as kilograms of carbon dioxide equivalent emissions (kgCO2e) per person-year. Secondary outcomes explored the effect of baseline symptom control and adherence (maintenance budesonide DPI arm only) on carbon footprint.

RESULTS

As-needed budesonide/formoterol DPI was associated with 95.8% and 93.6% lower carbon footprint compared with as-needed salbutamol pMDI (least-squares mean 1.1 versus 26.2 kgCO2e; difference -25.0, 95% CI -29.7 to -20.4; p<0.001) and maintenance budesonide DPI plus as-needed salbutamol pMDI (least-squares mean 1.1 versus 17.3 kgCO2e; difference -16.2, 95% CI -20.9 to -11.6; p<0.001), respectively. There was no statistically significant evidence that treatment differences in carbon footprint depended on baseline symptom control or adherence in the maintenance budesonide DPI arm.

CONCLUSIONS

The as-needed budesonide/formoterol DPI treatment option was associated with a markedly lower carbon footprint than as-needed salbutamol pMDI and maintenance budesonide DPI plus as-needed salbutamol pMDI.

Asthma management with triple ICS/LABA/LAMA combination to reduce the risk of exacerbation: an umbrella review compliant with the PRIOR statement

INTRODUCTION

According to Global Initiative for Asthma (GINA) guidelines, long-acting muscarinic antagonists (LAMAs) should be considered as add-on therapy in patients with asthma that remains uncontrolled, despite treatment with medium-dose (MD) or high-dose (HD) inhaled corticosteroids (ICS)/long-acting β2-agonist (LABA) combinations. In patients ≥ 18 years, LAMA may be added in triple combination with an ICS and a LABA. To date, the precise efficacy of triple ICS/LABA/LAMA combination remains uncertain concerning the impact on exacerbation risk in patients with uncontrolled asthma. Therefore, an umbrella review was performed to systematically summarize available data on the effect of triple ICS/LABA/LAMA combination on the risk of asthma exacerbation.

METHODS

An umbrella review has been performed according to the PRIOR statement.

RESULTS

The overall results obtained from 5 systematic reviews and meta-analyses suggest that triple ICS/LABA/LAMA combination reduces the risk of asthma exacerbation. HD-ICS showed a greater effect particularly in reducing severe asthma exacerbation, especially in patients with evidence of type 2 inflammation biomarkers.

CONCLUSIONS

The findings of this umbrella review suggest an optimization of ICS dose in triple ICS/LABA/LAMA combination, based on the severity of exacerbation and type 2 biomarkers expression.

Risk Factors for Acute Asthma Exacerbations in Adults With Mild Asthma

BACKGROUND

Although individuals with mild asthma account for 30% to 40% of acute asthma exacerbations (AAEs), relatively little attention has been paid to risk factors for AAEs in this population.

OBJECTIVE

To identify risk factors associated with AAEs in patients with mild asthma.

METHODS

This was a retrospective cohort study. We used administrative data from a large managed care organization to identify 199,010 adults aged 18 to 85 years who met study criteria for mild asthma between 2013 and 2018. An asthma-coded qualifying visit (index visit) was identified for each patient. We then used information at the index visit or from the year before the index visit to measure potential risk factors for AAEs in the subsequent year. An AAE was defined as either an asthma-coded hospitalization or emergency department visit, or an asthma-related systemic corticosteroid administration (intramuscular or intravenous) or oral corticosteroid dispensing. Poisson regression models with robust SEs were used to estimate the adjusted risk ratios for future AAEs.

RESULTS

In the study cohort, mean age was 44 years and 64% were female; 6.5% had AAEs within 1 year after the index visit. In multivariate models, age, sex, race, ethnicity, smoking status, body mass index, prior acute asthma care, and a variety of comorbidities and other clinical characteristics were significant predictors for future AAE risk.

CONCLUSION

Population-based disease management strategies for asthma should be expanded to include people with mild asthma in addition to those with moderate to severe disease.

A network meta-analysis of the association between patient traits and response to regular dosing with ICS plus short-acting β2-agonist reliever or ICS/formoterol reliever only in mild asthma

INTRODUCTION/BACKGROUND

Mild asthma treatment recommendations include intermittent inhaled corticosteroid (ICS)/formoterol dosing or regular ICS dosing with short-acting β2-agonist reliever. Due to the heterogeneity of asthma, identification of traits associated with improved outcomes to specific treatments would be clinically beneficial.

AIMS/OBJECTIVES

To assess the impact of patient traits on treatment outcomes of regular ICS dosing compared with intermittent ICS/formoterol dosing, a systematic literature review (SLR) and network meta-analysis (NMA) was conducted. Searches identified randomised controlled trials (RCTs) of patients with asthma aged ≥12 years, containing ≥1 regular ICS dosing or intermittent ICS/formoterol dosing treatment arm, reporting traits and outcomes of interest.

RESULTS

The SLR identified 11 RCTs of mild asthma, of 14,516 patients. A total of 11 traits and 11 outcomes of interest were identified. Of these, a feasibility assessment indicated possible assessment of three traits (age, baseline lung function, smoking history) and two outcomes (exacerbation rate, change in lung function). The NMA found no significant association of any trait with any outcome with regular ICS dosing relative to intermittent ICS/formoterol dosing. Inconsistent reporting of traits and outcomes between RCTs limited analysis.

CONCLUSIONS

This is the first systematic analysis of associations between patient traits and differential treatment outcomes in mild asthma. Although the traits analysed were not found to significantly interact with relative treatment response, inconsistent reporting from the RCTs prevented assessment of some of the most clinically relevant traits and outcomes, such as adherence. More consistent reporting of respiratory RCTs would provide more comparable data and aid future analyses.

Budesonide Attains Its Wide Clinical Profile by Alternative Kinetics

The introduction of inhaled corticosteroids (ICSs) changed over a few decades the treatment focus of mild-to-moderate asthma from bronchodilation to reduction in inflammation. This was achieved by inhaling a suitable corticosteroid (CS), giving a high, protracted airway concentration at a low total dose, thereby better combining efficacy and tolerance than oral therapy. Successful trials with the potent, lipophilic "skin" CS beclomethasone dipropionate (BDP) paved the way, suggesting that ICSs require a very low water solubility, prolonging their intraluminal dissolution within airways. The subsequent ICS development, with resulting clinical landmarks, is exemplified here with budesonide (BUD), showing that a similar efficacy/safety relationship is achievable by partly alternative mechanisms. BUD is much less lipophilic, giving it a 100-fold higher water solubility than BDP and later developed ICSs, leading to its more rapid intraluminal dissolution and faster airway and systemic uptake rates. In airway tissue, a BUD fraction is reversibly esterified to intracellular fatty acids, a lipophilic conjugate, which prolongs airway efficacy. Another mechanism is that the rapidly absorbed bulk fraction, via short plasma peaks, adds anti-inflammatory activity at the blood and bone marrow levels. Importantly, these plasma peaks are too short to provoke systemic adverse actions. Controlled clinical trials with BUD changed the use of ICS from a last resort to first-line treatment. Starting ICS treatment immediately after diagnosis ("early intervention") became a landmark for BUD. An established dose response made BUD suitable for the treatment of patients with all degrees of asthma severity. With the development of the budesonide/formoterol combination inhaler (BUD/FORM), BUD contributed to the widely used BUD/FORM maintenance and reliever therapy (MART). Recent studies demonstrated the value of BUD/FORM as a generally recommended as-needed therapy for asthma ("anti-inflammatory reliever", AIR). These abovementioned qualities have all influenced international asthma management and treatment guidelines.

The Role of ICS-Containing Rescue Therapy Versus SABA Alone in Asthma Management Today

The Global Initiative for Asthma (GINA) recommends that short-acting β2-agonist (SABA) monotherapy should no longer be prescribed, and that as-needed combination inhaled corticosteroids (ICS)-formoterol is the preferred reliever therapy in adults and adolescents with mild asthma. These recommendations are based on the risks of SABA monotherapy, the evidence that ICS-formoterol reliever therapy markedly decreases the occurrence of severe asthma exacerbations compared with SABA reliever therapy alone, and because ICS-formoterol reliever therapy has a favorable risk/benefit profile compared with maintenance ICS plus SABA reliever therapy. Data supporting the use of combination ICS-albuterol reliever therapy in mild asthma are more limited, but there are studies that inform its use in this population. In this review, we compare, using a pros and cons format, the (1) long-term safety and efficacy of ICS-formoterol reliever therapy versus SABA reliever therapy alone, (2) long-term safety and efficacy of ICS-albuterol reliever therapy versus SABA reliever therapy alone, (3) immediate bronchodilator effects of ICS-formoterol versus SABA alone, and (4) clinical and regulatory factors that may inform reliever therapy prescription decisions. By presenting the evidence of these reliever inhaler options, we hope to inform the reader while also calling for necessary future effectiveness and implementation research.

Treatable Traits in Pregnant Women with Asthma

BACKGROUND

Asthma is the most common chronic respiratory disease in pregnancy, affecting approximately 8-10% of pregnant women. Uncontrolled asthma is associated with adverse perinatal outcomes, including low birth weight, preterm birth, and maternal complications such as pre-eclampsia.

SUMMARY

A current approach to the management of chronic airway diseases is based on targeting treatable traits. The aim of this review was to define treatable traits in pregnant women with asthma based on recent literature and to determine personalized treatment options according to these traits. Traits addressed in this review that may improve asthma control and pregnancy outcomes are fractional exhaled nitric oxide-based asthma monitoring and treatment, medication adherence and inhalation technique, impaired lung function, smoking cessation and comorbidity including psychological conditions (depression and anxiety), obesity, rhinitis, gastroesophageal reflux disease, chronic rhinosinusitis with or without nasal polyps, and sleep apnea.

KEY MESSAGES

All the treatable traits discussed have the potential to improve asthma control and pregnancy outcomes in pregnant women with asthma. Further research is needed to determine which management approaches are best to improve asthma control during pregnancy, to identify other relevant treatable traits, and to determine whether the treatable trait approach is feasible and beneficial in pregnant women with asthma.

Systematic literature review of traits and outcomes reported in randomised controlled trials of asthma with regular dosing of inhaled corticosteroids with short-acting β2-agonist reliever, as-needed ICS/formoterol, or ICS/formoterol maintenance and reliever therapy

INTRODUCTION

Asthma treatments based solely on diagnostic label do not benefit patients equally. To identify patient traits that may be associated with improved treatment response to regular inhaled corticosteroid (ICSs) dosing with short-acting β2-agonist reliever or ICS/formoterol-containing therapy, a systematic literature review (SLR) was conducted.

METHODS

Searches of databases including MEDLINE and Embase identified randomised controlled trials (RCTs) of patients with asthma, aged ≥12 years, published 1998-2022, containing ≥1 regular ICS dosing or ICS/formoterol-containing treatment arm, and reporting patient traits and outcomes of interest. Relevant data was extracted and underwent a feasibility assessment to determine suitability for meta-analysis.

RESULTS

The SLR identified 39 RCTs of 72,740 patients and 90 treatment arms, reporting 11 traits and 11 outcomes. Five patient traits (age, body mass index, FEV1, smoking history, asthma control) and five outcomes (exacerbation rate, lung function, asthma control, adherence, time to first exacerbation) were deemed feasible for inclusion in meta-analyses due to sufficient comparable reporting. Subgroups of clinical outcomes stratified by levels of patient traits were reported in 16 RCTs.

CONCLUSION

A systematic review of studies of regular ICS dosing with SABA or ICS/formoterol-containing treatment strategies in asthma identified consistent reporting of five traits and outcomes, allowing exploration of associations with treatment response. Conversely, many other traits and outcomes, although being potentially relevant, were inconsistently reported and limited subgroup reporting meant analyses of treatment response for subgroups of traits was not possible. We recommend more consistent measurement and reporting of clinically relevant patient traits and outcomes in respiratory RCTs.

Mild asthma is not mild: risk factors and predictive biomarkers for severe acute exacerbations and progression in mild asthma

INTRODUCTION

Asthma is a common chronic respiratory disease characterized by chronic airway inflammation, airway hyperresponsiveness, reversible airflow limitation, and airway remodeling. Mild asthma is the most common type of asthma, but it is the most neglected. Sometimes mild asthma can lead to acute severe exacerbations or even death.

AREAS COVERED

This article reviews the epidemiology, risk factors, and possible predictors of acute severe exacerbations and disease progression in mild asthma to improve the understanding of mild asthma and its severe acute exacerbations and progression.

EXPERT OPINION

There is a necessity to improve asthma patient categorization and redefine mild asthma's concept to heighten patient and physician attention. Identifying mild asthma patients that are highly vulnerable to severe acute exacerbations and researching the mechanisms are future prioritizations.

Phenotyping the Responses to Systemic Corticosteroids in the Management of Asthma Attacks (PRISMA): protocol for an observational and translational pilot study

INTRODUCTION

Asthma and its associated exacerbation are heterogeneous. Although severe asthma attacks are systematically prescribed corticosteroids and often antibiotics, little is known about the variability of response to these therapies. Blood eosinophils and fractional exhaled nitric oxide (FeNO) are type 2 inflammation biomarkers that have established mechanistic, prognostic and theragnostic values in chronic asthma, but their utility in acute asthma is unclear. We speculate that the clinical and biological response to those treatments varies according to inflammometry and microbiological test results.

METHODS AND ANALYSIS

An observational longitudinal pilot study with multimodal clinical and translational assessments will be performed on 50 physician-diagnosed ≥12-year-old asthmatics presenting with an asthma attack and 12 healthy controls, including blood eosinophil count (venous and point-of-care (POC) capillary blood), FeNO and testing for airway infection (sputum cultures and POC nasopharyngeal swabs). People with asthma will be assessed on day 0 and after a 7-day corticosteroid course, with home monitoring performed in between. The primary analysis will be the change in the forced expiratory volume in 1 s according to type 2 inflammatory status (blood eosinophils ≥0.15×109/L and/or FeNO ≥25 ppb) after treatment. Key secondary analyses will compare changes in symptom scores and the proportion of patients achieving a minimal clinically important difference. Exploratory analyses will assess the relationship between clinical, lung function, inflammatory and microbiome parameters; satisfaction plus reliability indices of POC tests; and sex-gender variability in treatment response. Ultimately, this pilot study will serve to plan a larger trial comparing the clinical and biological response to systemic corticosteroids according to inflammatory biomarkers, offering valuable guidance for more personalised therapeutic strategies in asthma attacks.

ETHICS AND DISSEMINATION

The protocol has been approved by the Research Ethics Committee of the CIUSSS de l'Estrie-CHUS, Sherbrooke, Quebec, Canada (#2023-4687). Results will be communicated in an international meeting and submitted to a peer-reviewed journal.

TRIAL REGISTRATION NUMBER

ClinicalTrials.gov Registry (NCT05870215).

European Respiratory Society short guidelines for the use of as-needed ICS/formoterol in mild asthma

Recent clinical trials of as-needed fixed-dose combination of inhaled corticosteroid (ICS)/formoterol have provided new evidence that may warrant a reconsideration of current practice. A Task Force was set up by the European Respiratory Society to provide evidence-based recommendations on the use of as-needed ICS/formoterol as treatment for mild asthma. The Task Force defined two questions that were assessed using the GRADE (Grading of Recommendations, Assessment, Development and Evaluation) approach. The Task Force utilised the outcomes to develop recommendations for a pragmatic guideline for everyday clinical practice. The Task Force suggests that adults with mild asthma use as-needed ICS/formoterol instead of regular ICS maintenance treatment plus as-needed short-acting β2-antagonist (SABA) and that adolescents with mild asthma use either as-needed ICS/formoterol or ICS maintenance treatment plus as-needed SABA (conditional recommendation; low certainty of evidence). The recommendation for adults places a relatively higher value on the reduction of systemic corticosteroid use and the outcomes related to exacerbations, and a relatively lower value on the small differences in asthma control. Either treatment option is suggested for adolescent patients as the balance is very close and data more limited. The Task Force recommends that adult and adolescent patients with mild asthma use as-needed ICS/formoterol instead of as-needed SABA (strong recommendation; low certainty of evidence). This recommendation is based on the benefit of as-needed ICS/formoterol in mild asthma on several outcomes and the risks related to as-needed SABA in the absence of anti-inflammatory treatment. The implementation of this recommendation is hampered in countries (including European Union countries) where as-needed ICS/formoterol is not approved for mild asthma.

Evaluating as-needed inhaled corticosteroid strategies in asthma: expanding the benefits to mild asthma

INTRODUCTION

Adherence to regular anti-inflammatory treatment is commonly low, and short-acting β2 agonist (SABA) overuse is common in patients with asthma, leading to an increased risk of asthma-related adverse events.

AREAS COVERED

Given the pivotal role of inflammation in asthma, multiple as-needed inhaled corticosteroid (ICS)-containing therapies have been developed, leading to a reduction in asthma exacerbations and improvement in symptom control. Currently, as-needed ICS/formoterol is one of the most commonly available formulations; however, other combinations such as ICS/SABA have been shown to be superior to as-needed SABA alone. Therefore, we performed a comprehensive review of the available scientific literature to enhance the advantages and disadvantages of each combination in clinical practice.

EXPERT OPINION

The future direction we foresee in asthma management consists in abandoning as-needed short-acting bronchodilators in favor of as-needed ICS-containing therapies. Each patient is unique and differs from others; consequently, a single option will not fit everyone. Patients' and physicians' awareness of this perspective can be reached through the development of multiple therapeutic options suitable for each condition that can be found in 'real life'.

Mild asthma: Lessons learned and remaining questions

Patients living with mild disease represent the largest proportion of asthma patients. There are significant challenges in proposing a definition that would best describe these patients, while also accurately identifying at-risk individuals. Current literature suggests considerable inflammatory and clinical heterogeneity within this group. Research has shown that these patients are at risk of poor control, exacerbations, lung function decline, and death. Despite conflicting data on its prevalence, eosinophilic inflammation appears to be a predictor of poorer outcomes in mild asthma. There is an immediate need to better understand phenotypic clusters in mild asthma. It is also important to understand factors that influence disease progression and remission, as it is evident that both vary in mild asthma. Guided by robust literature that supports inhaled corticosteroid-based strategies over short-acting beta-agonist (SABA) reliant regimens, the management of these patients has evolved considerably. Unfortunately, SABA use remains high in clinical practice despite strong advocacy from the Global Initiative for Asthma. Future mild asthma research should explore the role of biomarkers, develop prediction tools based on composite risk scores, and explore targeted therapies at least for at-risk individuals.

Questions in Mild Asthma: An Official American Thoracic Society Research Statement

Background: Patients with mild asthma are believed to represent the majority of patients with asthma. Disease-associated risks such as exacerbations, lung function decline, and death have been understudied in this patient population. There have been no prior efforts from major societies to describe research needs in mild asthma. Methods: A multidisciplinary, diverse group of 24 international experts reviewed the literature, identified knowledge gaps, and provided research recommendations relating to mild asthma definition, pathophysiology, and management across all age groups. Research needs were also investigated from a patient perspective, generated in conjunction with patients with asthma, caregivers, and stakeholders. Of note, this project is not a systematic review of the evidence and is not a clinical practice guideline. Results: There are multiple unmet needs in research on mild asthma driven by large knowledge gaps in all areas. Specifically, there is an immediate need for a robust mild asthma definition and an improved understanding of its pathophysiology and management strategies across all age groups. Future research must factor in patient perspectives. Conclusions: Despite significant advances in severe asthma, there remain innumerable research areas requiring urgent attention in mild asthma. An important first step is to determine a better definition that will accurately reflect the heterogeneity and risks noted in this group. This research statement highlights the topics of research that are of the highest priority. Furthermore, it firmly advocates the need for engagement with patient groups and for more support for research in this field.

Peripheral blood eosinophilia in adult asthmatic patients and its association with the severity of asthma

BACKGROUND

Asthma is a diverse disease with various etiologic bases. Severe asthma can be associated with increased mortality, hospitalization, and decreased quality of life for asthma patients. High blood eosinophil counts were associated with severe asthma, but recent studies have failed to confirm this as a marker of severe asthma among adult asthma patients. As a result, the purpose of this study was to determine the association between the severity of asthma and high blood eosinophil count.

METHODOLOGY

A simple random sampling technique was used to select 291 asthmatic patients for an institution-based cross-sectional study. Socio-demographic, behavioral, and clinical characteristics were collected by using a pre-tested structured questionnaire. Four milliliters of venous blood were collected from asthmatic patients for complete blood count and peripheral morphology assessment. The eosinophil count was analyzed by the Unicel DxH 800 (Beckman Coulter, Ireland) analyzer. A statistical package for social science version 20 (SPSS) software was used to analyze the data. The non-parametric (Mann-Whitney U) test was used to compare the eosinophil count with different background variables. A binary logistic regression analysis was used to assess the factors associated with eosinophilia. A p-value less than 0.05 in multivariable logistic regression analysis was considered statistically significant.

RESULT

In this study, the overall magnitude of eosinophilia was 19.6% (95% CI = 14.8-24.1). Being admitted to the emergency department (AOR = 0.25; 95% CI: 0.09-0.69, p = 0.007) and being female (AOR = 0.49; 95% CI: 0.26-0.9, p = 0.025) were shown to have a statistically significant association with eosinophilia. Moreover, the absolute eosinophil count was significantly higher among asthmatic patients infected with intestinal parasitic infection (p < 0.045).

CONCLUSION

Being female and admission to the emergency department were negatively associated with eosinophilia. Lack of eosinophilia can be related to the low-T2 asthma phenotype. The absolute eosinophil counts were higher among intestinal parasite-infected patients. Therefore, different biomarkers will be considered for the proper diagnosis and management of adult asthma patients.

Airway inflammation and hyperresponsiveness in subjects with respiratory symptoms and normal spirometry

BACKGROUND

Subjects without a previous history of asthma, presenting with unexplained respiratory symptoms and normal spirometry, may exhibit airway hyperresponsiveness (AHR) in association with underlying eosinophilic (type 2 (T2)) inflammation, consistent with undiagnosed asthma. However, the prevalence of undiagnosed asthma in these subjects is unknown.

METHODS

In this observational study, inhaled corticosteroid-naïve adults without previously diagnosed lung disease reporting current respiratory symptoms and showing normal pre- and post-bronchodilator spirometry underwent fractional exhaled nitric oxide (F _ENO) measurement, methacholine challenge testing and induced sputum analysis. AHR was defined as a provocative concentration of methacholine causing a 20% fall in forced expiratory volume in 1 s (PC₂₀) <16 mg·mL^-1 and T2 inflammation was defined as sputum eosinophils >2% and/or F _ENO >25 ppb.

RESULTS

Out of 132 subjects (mean±sd age 57.6±14.2 years, 52% female), 47 (36% (95% CI 28-44%)) showed AHR: 20/132 (15% (95% CI 9-21%)) with PC₂₀ <4 mg·mL^-1 and 27/132 (21% (95% CI 14-28%)) with PC₂₀ 4-15.9 mg·mL^-1. Of 130 participants for whom sputum eosinophils, F _ENO or both results were obtained, 45 (35% (95% CI 27-43%)) had T2 inflammation. 14 participants (11% (95% CI 6-16%)) had sputum eosinophils >2% and PC₂₀ ≥16 mg·mL^-1, suggesting eosinophilic bronchitis. The prevalence of T2 inflammation was significantly higher in subjects with PC₂₀ <4 mg·mL^-1 (12/20 (60%)) than in those with PC₂₀ 4-15.9 mg·mL^-1 (8/27 (30%)) or ≥16 mg·mL^-1 (25/85 (29%)) (p=0.01).

CONCLUSIONS

Asthma, underlying T2 airway inflammation and eosinophilic bronchitis may remain undiagnosed in a high proportion of symptomatic subjects in the community who have normal pre- and post-bronchodilator spirometry.

"As-Needed" Inhaled Corticosteroids for Patients With Asthma

Prevention of severe asthma exacerbations is a primary management goal for asthma across the severity spectrum. Inhaled corticosteroids (ICSs) decrease the risk of asthma exacerbations, but patient adherence to ICS-containing medications as a daily maintenance therapy is poor, and many patients overuse short-acting beta2-agonist relievers; both are associated with increased risk of severe exacerbations and death. Airway inflammation also varies over time, influenced by exposures such as viral infections and allergen. As-needed ICS strategies, in which patients receive ICSs (or additional ICSs, if already taking controller therapy) whenever they take their reliever inhaler, empower patients to adjust their ICS intake in response to symptom fluctuation. These strategies can improve asthma morbidity outcomes, particularly by reducing severe exacerbations and reducing the risk of adverse effects of oral corticosteroids. In this review, the evidence for combination ICS-formoterol in a single inhaler, ICS and short-acting beta2-agonists in separate inhalers, and combination ICS-albuterol in a single inhaler is presented, along with practical considerations, evidence gaps, and implications for clinical practice for each strategy, presented by level of asthma severity and age group. Improving access to such strategies on a global scale is imperative to improve asthma outcomes and achieve equity across populations.

Toward a Predict and Prevent Approach in Obstructive Airway Diseases

Asthma and chronic obstructive pulmonary disease are currently diagnosed and treated after the demonstration of variable airflow limitation and symptoms. Under this framework, undiagnosed and unchecked airway inflammation is associated with recurrent acute attacks, airway remodeling, airflow limitation, adverse effects of corticosteroids, and impaired quality of life, ultimately leading to the collection of side effects termed "people remodeling." This one-size-fits-all damage control approach aims to control symptoms and treat exacerbations rather than modify the underlying disease process. The advent of highly effective therapies targeting proximal drivers of airway inflammation calls for a paradigm shift; upstream-acting therapies offer potential to alter the disease course and achieve clinical remission. We propose moving away from downstream firefighting and toward a "predict and prevent" model, measuring inflammation and providing anti-inflammatory therapy early, without waiting for further clinical deterioration. Much in the same way that high blood pressure and cholesterol are used to predict and prevent heart attacks, in asthma, elevated blood eosinophils and/or exhaled nitric oxide can be used to predict and prevent asthma attacks. We also advocate moving research further upstream by identifying patients with subclinical airway inflammation or disease who may be at risk of progressing to airflow limitation and associated morbidities and intervening early to prevent them. In summary, we call for a predict and prevent approach in obstructive airway disease.

The ICS/Formoterol Reliever Therapy Regimen in Asthma: A Review

The Global Initiative for Asthma recommends that low-dose inhaled corticosteroid (ICS)/formoterol be preferred to short-acting beta₂-agonists as reliever therapy in adolescents and adults with asthma, across the range of asthma severity. This recommendation represents the most fundamental change in asthma management for many decades. In this commentary, we review the rationale for combination ICS/formoterol therapy, the evidence on which this recommendation has been made, the limitations in the evidence, the practical issues relevant to the implementation of ICS/formoterol reliever-based regimens in clinical practice, and the emerging evidence for the efficacy and safety of combination ICS/salbutamol reliever therapy regimens.

Asthma Exacerbations in Severe Asthma: Why Systemic Corticosteroids May not Always Be the Best Treatment Option

Purpose

Advances in the management of severe, eosinophilic asthma have improved, but asthma exacerbations continue to occur. This review aims to look at the evidence we have about why exacerbations may occur; their phenotype and why oral corticosteroids may not always be the best treatment option for all exacerbation of symptoms in individuals with severe asthma.

Recent findings

Studies dating back to the 1990s showed that asthma exacerbations across the spectrum of asthma severity were of different inflammatory endotypes. In addition, there is a wealth of evidence suggesting that eosinophilic inflammation is very responsive to corticosteroid therapy, but that non-eosinophilic inflammation is less so. Two recent UK-based studies have undertaken systematic phenotyping of exacerbations in severe asthma and have shown that there are a significant minority of exacerbation events with an increase in asthma symptoms, fall in lung function, but without evidence of raised T2 biomarkers.

Summary

The evidence to date would suggest that T2 biomarker low asthma exacerbations do not benefit from the administration of oral corticosteroids; in fact, the effect of the oral corticosteroids is harmful. However, there is a paucity of data to answer this question directly. Further research is needed to assess the evolution of non-T2 exacerbations not treated with OCS in a randomised, placebo-controlled, manner.

Budesonide/formoterol maintenance and reliever therapy versus fluticasone/salmeterol fixed-dose treatment in patients with COPD

BACKGROUND

Maintenance and reliever therapy (MART) with inhaled corticosteroid (ICS)/formoterol effectively reduces exacerbations in asthma. We aimed to investigate its efficacy compared with fixed-dose fluticasone/salmeterol in chronic obstructive pulmonary disease (COPD).

METHODS

Patients with COPD and ≥1 exacerbation in the previous 2 years were randomly assigned to open-label MART (Spiromax budesonide/formoterol 160/4.5 µg 2 inhalations twice daily+1 prn) or fixed-dose therapy (Diskus fluticasone propionate/salmeterol combination (FSC) 500/50 µg 1 inhalation twice daily+salbutamol 100 µg prn) for 1 year. The primary outcome was rate of moderate/severe exacerbations, defined by treatment with oral prednisolone and/or antibiotics.

RESULTS

In total, 195 patients were randomised (MART Bud/Form n=103; fixed-dose FSC n=92). No significant difference was seen between MART and FSC therapy in exacerbation rates (1.32 vs 1.32 /year, respectively, rate ratio 1.05 (95% CI 0.79 to 1.39); p=0.741). No differences in lung function parameters or health status were observed. Total ICS dose was significantly lower with MART than FSC therapy (budesonide-equivalent 928 µg/day vs 1747 µg/day, respectively, p<0.05). Similar proportions of patients reported adverse events (MART Bud/Form: 73% vs fixed-dose FSC: 68%, p=0.408) and pneumonias (MART: 5% vs FSC: 1%, p=0.216).

CONCLUSIONS

This first study of MART in COPD found that budesonide/formoterol MART might be similarly effective to fluticasone/salmeterol fixed-dose therapy in moderate to severe patients with COPD, at a lower daily ICS dosage. Further evidence is needed about long-term safety.

Effect of Stepping Up to High-Dose Inhaled Corticosteroids in Patients With Asthma: UK Database Study

BACKGROUND

It is unclear whether patients with asthma benefit from stepping up to high-dose inhaled corticosteroids (ICSs).

OBJECTIVE

To determine the effectiveness of stepping up to high-dose ICSs.

METHODS

A historic cohort study of patients with asthma (≥13 years old), identified from 2 large UK electronic medical record databases, was conducted. Patients who remained on medium-dose ICSs were compared with those who stepped up from medium- to high-dose ICSs, whereas patients who stepped up from low- to medium-dose ICSs were compared with those who stepped up from low- to high-dose ICSs. Time to first severe exacerbation (primary outcome) between treatment groups was compared using multivariable Cox proportional hazards models, and the number of exacerbations and antibiotics courses was analyzed using negative binomial regression. Inverse probability of treatment weighting was used to handle confounding.

RESULTS

The mean follow-up time to first exacerbation was 2.7 ± 2.7 years for those who remained on stable medium-dose ICSs and 2.0 ± 2.2 years for those who stepped up from medium- to high-dose ICSs. A similar pattern was noted for those who stepped up from low- to medium-dose ICSs (2.6 ± 2.5 years) and from low- to high-dose ICSs (2.3 ± 2.5 years). Patients who stepped up from medium- to high-dose ICSs (n = 6879) had a higher risk of exacerbations during follow-up compared with those who remained on medium-dose ICSs (n = 51,737; hazard ratio, 1.17; 95% CI, 1.12-1.22). This was similar in patients stepping up from low- to high-dose (n = 3232) compared with low- to medium-dose (n = 12,659) ICSs (hazard ratio, 1.10; 95% CI, 1.04-1.17). A step-up to high-dose ICSs was also associated with a higher number of asthma exacerbations and antibiotics courses. No significant difference in associations was found across subgroups of patients with different blood eosinophil counts.

CONCLUSIONS

We found no evidence that a step-up to high-dose ICSs is effective in preventing future asthma exacerbations.

Diagnosis and Assessment of the Asthmas

Optimizing asthma diagnosis is an essential part of global strategies to reduce the excessive illness burden from asthma. New understanding about how to address the complexity and heterogeneity of the different forms of asthma means that asthma diagnosis now requires a compound diagnostic approach and label. Eliciting the typical symptoms and abnormal physiology of variable airflow limitation permits the recognition of asthma, and the identification of further features, such as eosinophilic or type 2 inflammation, allows a compound diagnostic label of eosinophilic asthma. This conveys key information about future exacerbation risk and likely treatment responsiveness. Treatable traits are a useful way to implement this new approach to diagnosis. Targeted assessment is used to inform a specific treatment plan in a pragmatic and iterative process.

Baseline FeNO Independently Predicts the Dupilumab Response in Patients With Moderate-to-Severe Asthma

BACKGROUND

FeNO may have a role as both a prognostic and predictive biomarker in combination with eosinophils for assessing responsiveness to some biological therapies.

OBJECTIVE

We evaluated the value of baseline FeNO, adjusted for baseline blood eosinophil levels and other clinical characteristics, as an independent predictor of treatment response to dupilumab in patients with uncontrolled moderate-to-severe asthma.

METHODS

We performed a post hoc analysis of LIBERTY ASTHMA QUEST (NCT02414854), a phase 3, double-blind study in patients aged 12 years and older with uncontrolled moderate-to-severe asthma, who received dupilumab 200 or 300 mg, or placebo every 2 weeks up to 52 weeks. We assessed the annualized event rate of severe exacerbations and least-squares mean change from baseline in prebronchodilator FEV₁ at weeks 12 and 52 in relationship to baseline FeNO, adjusted for eosinophils and other clinical characteristics.

RESULTS

The annualized event rate increased with increasing baseline FeNO in placebo and decreased in dupilumab groups. The relative risk of severe exacerbations was 22·7%, 58·3%, and 69·3% lower for dupilumab versus placebo for the FeNO less than 25, 25 to less than 50, and 50 and greater parts per billion subgroups. The magnitude of FEV₁ improvement increased with higher baseline FeNO for dupilumab and was consistent across the continuum of FeNO levels in placebo. Both findings were independent of blood eosinophil levels. Significant differences were observed between FeNO subgroups.

CONCLUSIONS

Increased baseline FeNO was associated with greater clinical effects in dupilumab versus placebo independently of eosinophil levels and other clinical characteristics.

A machine learning approach to characterize patients with asthma exacerbation attending an acute care setting

BACKGROUND

One of the main problems in poorly controlled asthma is the access to the Emergency Department (ED). Using a machine learning (ML) approach, the aim of our study was to identify the main predictors of severe asthma exacerbations requiring hospital admission.

METHODS

Consecutive patients with asthma exacerbation were screened for inclusion within 48 hours of ED discharge. A k-means clustering algorithm was implemented to evaluate a potential distinction of different phenotypes. K-Nearest Neighbor (KNN) as instance-based algorithm and Random Forest (RF) as tree-based algorithm were implemented in order to classify patients, based on the presence of at least one additional access to the ED in the previous 12 months.

RESULTS

To train our model, we included 260 patients (31.5% males, mean age 47.6 years). Unsupervised ML identified two groups, based on eosinophil count. A total of 86 patients with eosinophiles ≥370 cells/µL were significantly older, had a longer disease duration, more restrictions to daily activities, and lower rate of treatment compared to 174 patients with eosinophiles <370 cells/μL. In addition, they reported lower values of predicted FEV₁ (64.8±12.3% vs. 83.9±17.3%) and FEV₁/FVC (71.3±9.3 vs. 78.5±6.8), with a higher amount of exacerbations/year. In supervised ML, KNN achieved the best performance in identifying frequent exacerbators (AUROC: 96.7%), confirming the importance of spirometry parameters and eosinophil count, along with the number of prior exacerbations and other clinical and demographic variables.

CONCLUSIONS

This study confirms the key prognostic value of eosinophiles in asthma, suggesting the usefulness of ML in defining biological pathways that can help plan personalized pharmacological and rehabilitation strategies.

Phenotyping, Precision Medicine, and Asthma

The traditional one-size-fits all approach based on asthma severity is archaic. Asthma is a heterogenous syndrome rather than a single disease entity. Studies evaluating observable characteristics called phenotypes have elucidated this heterogeneity. Asthma clusters demonstrate overlapping features, are generally stable over time and are reproducible. What the identification of clusters may have failed to do, is move the needle of precision medicine meaningfully in asthma. This may be related to the lack of a straightforward and clinically meaningful way to apply what we have learned about asthma clusters. Clusters are based on both clinical factors and biomarkers. The use of biomarkers is slowly gaining popularity, but phenotyping based on biomarkers is generally greatly underutilized even in subspecialty care. Biomarkers are more often used to evaluate type 2 (T2) inflammatory signatures and eosinophils (sputum and blood), fractional exhaled nitric oxide (FeNO) and serum total and specific immunoglobulin (Ig) E reliably characterize the underlying inflammatory pathways. Biomarkers perform variably and clinicians must be familiar with their advantages and disadvantages to accurately apply them in clinical care. In addition, it is increasingly clear that clinical features are critical in understanding not only phenotypic characterization but in predicting response to therapy and future risk of poor outcomes. Strategies for asthma management will need to leverage our knowledge of biomarkers and clinical features to create composite scores and risk prediction tools that are clinically applicable. Despite significant progress, many questions remain, and more work is required to accurately identify non-T2 biomarkers. Adoption of phenotyping and more consistent use of biomarkers is needed, and we should continue to encourage this incorporation into practice.

May a different kinetic mode explain the high efficacy/safety profile of inhaled budesonide?

The claimed functional basis for ICSs in asthma and COPD is airway selectivity, attained by inhaling a potent, lipophilic compound with long local dissolution/absorption time. The development has been empirically based, resulting in five widely used ICSs. Among them, budesonide (BUD) deviates by being less lipophilic, leading to a more rapid systemic uptake with plasma peaks with some systemic anti-inflammatory activity. By this, BUD fits less well into the current pharmacological dogma of optimal ICS profile. In this review we compared the physicochemical, pharmacological and clinical properties of BUD, fluticasone propionate (FP) and fluticasone furoate (FF), representing different levels of lipophilicity, airway and systemic kinetics, focusing on their long-acting β2-agonist (LABA) combinations, in line with current GINA and GOLD recommendations. We are aware of the differences between formoterol (FORM) and the not rapid acting LABAs such as e.g. salmeterol and vilanterol but our comparisons are based on currently available combination products. A beclomethasone dipropionate (BDP)/FORM combination is also commented upon. Based on clinical comparisons in asthma and COPD, we conclude that the BUD/formoterol (BUD/FORM) combination is as effective and safe as the FP and FF combinations, and is in some cases even better as it can be used as "maintenance plus reliever therapy" (MART) in asthma and as maintenance in COPD. This is difficult to explain by current views of required ICS's/LABAs pharmacokinetic profiles. We propose that BUD achieves its efficacy by a combination of airway and systemic activity. The airway activity is dominating. The systemic activity contributes by plasma peaks, which are high enough for supportive anti-inflammatory actions at the blood and bone marrow levels but not sufficiently long to trigger a similar level of systemic adverse effects. This may be due to BUD's capacity to exploit a systemic differentiation mechanism as programmed for cortisol's various actions. This differentiation prospect can be reached only for an ICS with short plasma half-life. Here we present an alternative mode for an ICS to reach combined efficacy and safety, based on a poorly investigated and exploited physiological mechanism. A preference of this mode is broader versatility, due to that its straighter dose-response should allow a better adaptation to disease fluctuations, and that its rapid activity enables use as "anti-inflammatory reliever".

Artesunate: A review of its therapeutic insights in respiratory diseases

BACKGROUND

Artesunate, as a semi-synthetic artemisinin derivative of sesquiterpene lactone, is widely used in clinical antimalarial treatment due to its endoperoxide group. Recent studies have found that artesunate may have multiple pharmacological effects, indicating its significant therapeutic potential in multiple respiratory diseases.

PURPOSE

This review aims to summarize proven and potential therapeutic effects of artesunate in common respiratory disorders.

STUDY DESIGN

This review summarizes the pharmacological properties of artesunate and then interprets the function of artesunate in various respiratory diseases in detail, such as bronchial asthma, chronic obstructive pulmonary disease, lung injury, lung cancer, pulmonary fibrosis, coronavirus disease 2019, etc., on different target cells and receptors according to completed and ongoing in silico, in vitro, and in vivo studies (including clinical trials).

METHODS

Literature was searched in electronic databases, including Pubmed, Web of Science and CNKI with the primary keywords of 'artesunate', 'pharmacology', 'pharmacokinetics', 'respiratory disorders', 'lung', 'pulmonary', and secondary search terms of 'Artemisia annua L.', 'artemisinin', 'asthma', 'chronic obstructive lung disease', 'lung injury', 'lung cancer', 'pulmonary fibrosis', 'COVID-19' and 'virus' in English and Chinese. All experiments were included. Reviews and irrelevant studies to the therapeutic effects of artesunate on respiratory diseases were excluded. Information was sort out according to study design, subject, intervention, and outcome.

RESULTS

Artesunate is promising to treat multiple common respiratory disorders via various mechanisms, such as anti-inflammation, anti-oxidative stress, anti-hyperresponsiveness, anti-proliferation, airway remodeling reverse, induction of cell death, cell cycle arrest, etc. CONCLUSION: Artesunate has great potential to treat various respiratory diseases.

What is the added value of FeNO as T2 biomarker?

There is increasing evidence about the role of nitric oxide in type 2 (T2) immune response. Fraction of exhaled nitric oxide (FeNO) is a product of airways inflammation and it is increased in patients with asthma. Since Gustaffson published the first article about this biomarker in the 1990s, interest has continued to grow. Compared with other T2 biomarkers such as blood eosinophil count, induced sputum, or serum periostin, FeNO has some remarkable advantages, including its not invasive nature, easy repeatability, and possibility to be performed even in patients with severe airway obstruction. It is considered as an indicator of T2 inflammation and, by the same token, a useful predictor for inhaled steroid response. It is difficult to determine the utility of nitric oxide (NO) for initial asthma diagnosis. In such a heterogenous disease, a single parameter would probably not be enough to provide a complete picture. There is also an important variability among authors concerning FeNO cutoff values and the percentage of sensibility and specificity for diagnosis. Its high specificity indicates a potential role to “rule in” asthma; however, its lower sensibility could suggest a lower capacity to “rule out” this pathology. For this reason, if a diagnosis of asthma is being considered, FeNO should be considered along with other tests. FeNO has also shown its utility to detect response to steroids, adherence to treatment, and risk of exacerbation. Even though there is not enough quality of evidence to establish overall conclusions, FeNO could be an alternative procedure to diagnose or exclude asthma and also a predictive tool in asthma treated with corticosteroids.

Stepped treatment algorithm using budesonide-formoterol for chronic respiratory diseases: A single arm interventional study

Background

While the safety and efficacy of inhaled budesonide-formoterol, used as-needed for symptoms, has been established for patients with asthma, it has not been trialed in undifferentiated patients with chronic respiratory diseases. We aimed to assess the feasibility of a pragmatic intervention that entails a stepped algorithm using inhaled budesonide-formoterol (dry powder inhaler, 160μg/4.5μg per dose) for patients presenting with chronic respiratory diseases to three rural district hospitals in Hanoi, Vietnam.

Methods

We recruited patients with evidence of airflow obstruction on spirometry and/or symptoms consistent with asthma. The algorithm consisted of three steps: 1. as-needed inhaled budesonide-formoterol for symptoms, 2. maintenance plus as-needed inhaled budesonide-formoterol, and 3. referral to a higher-level healthcare facility. All participants started at step 1, with escalation to the next step at review visits if there had been exacerbation(s) or inadequate symptom control. Patients were followed for 12 months.

Results

Among 313 participants who started the treatment algorithm, 47.2% had ≥ 1 episode of acute respiratory symptoms requiring a visit to hospital or clinic and 35.4% were diagnosed with an exacerbation. Twelve months after enrolment, 50.7% still adhered to inhaled budesonide-formoterol at the recommended treatment step. The mean and median number of doses per day was 1.5 (standard deviation 1.2) doses and 1.3 (interquartile range 0.7–2.3) doses, respectively. The proportion of patients taking more than 800μg budesonide per day was 3.8%.

Conclusion

This novel therapeutic algorithm is feasible for patients with chronic respiratory diseases in a rural setting in Vietnam. Further studies are required to establish the effectiveness, safety and cost-effectiveness of similar approaches in different settings.

Trial registration

ACTRN12619000554167.

Thunderstorm asthma in seasonal allergic rhinitis: The TAISAR study

BACKGROUND

Asthma epidemics associated with thunderstorms have had catastrophic effects on individuals and emergency services. Seasonal allergic rhinitis (SAR) is present in the vast majority of people who develop thunderstorm asthma (TA), but there is little evidence regarding risk factors for TA among the SAR population.

OBJECTIVE

We sought to identify risk factors for a history of TA and hospital presentation in a cohort of individuals with SAR.

METHODS

This multicenter study recruited adults from Melbourne, Australia, with a past diagnosis of TA and/or self-reported SAR. Clinical information, spirometry results, white blood cell count, ryegrass pollen-specific (RGP-sp) IgE concentration, and fractional exhaled nitric oxide were measured to identify risk factors for a history of TA in individuals with SAR.

RESULTS

From a total of 228 individuals with SAR, 35% (80 of 228) reported SAR only (the I-SAR group), 37% (84 of 228) reported TA symptoms but had not attended hospital for treatment (the O-TA group), and 28% (64 of 228) had presented to the hospital for TA (the H-TA group). All patients in the H-TA group reported a previous asthma diagnosis. Logistic regression analysis of factors associated with O-TA and H-TA indicated that lower FEV1 value and an Asthma Control Questionnaire score higher than 1.5 were associated with H-TA. Higher blood RGP-sp IgE concentration, eosinophil counts, and fractional exhaled nitric oxide level were significantly associated with both O-TA and H-TA. Receiver operating curve analysis showed an RGP-sp IgE concentration higher than 10.1 kU/L and a prebronchodilator FEV1 value of 90% or lower to be biomarkers of increased H-TA risk.

CONCLUSION

Clinical tests can identify risk of a history of TA in individuals with SAR and thereby inform patient-specific treatment recommendations.

Should we apply a treatable traits approach to asthma care?

OBJECTIVE

To explore the evidence for adopting a "treatable traits" approach to asthma management.

DATA SOURCES

PubMed, Medline, and Google Scholar.

STUDY SELECTIONS

The above-mentioned databases were searched for randomized, controlled phase III or IV trials of adults containing the word "asthma" in the title published in the previous 10 years and for all articles containing the title words "treatable AND trait(s)," "asthma AND biomarker(s) OR smoking OR obesity OR laryngeal OR management" published within the previous 5 years. Articles were excluded if they were not published in English. Our search identified 257 articles for consideration. We also manually searched the reference lists of studies identified and searched the websites of the British Thoracic Society, European Respiratory Society, National Institute for Health and Care Excellence, and Global Initiative for Asthma for specific guidance related to asthma management.

RESULTS

The "treatable traits" are described within 3 domains of pulmonary, extrapulmonary, or behavioral and lifestyle traits. We consider whether treatment should be targeted toward these traits where they are present in asthma patients, based on currently available evidence, rather than increasing treatment in response to symptoms in line with current step-up, step-down asthma management guidelines.

CONCLUSION

We advocate that a treatable traits approach should be applied more broadly to the assessment and management of inadequately controlled asthma, rather than a step-up, step-down approach based on patient symptoms. This approach should be focused on the 2 treatable pulmonary traits of T_H2 inflammation and airflow obstruction along with smoking cessation, in the first instance.

Blood eosinophils, fractional exhaled nitric oxide and the risk of asthma attacks in randomised controlled trials: protocol for a systemic review and control arm patient-level meta-analysis for clinical prediction modelling

INTRODUCTION

The reduction of the risk of asthma attacks is a major goal of guidelines. The fact that type-2 inflammatory biomarkers identify a higher risk, anti-inflammatory responsive phenotype is potentially relevant to this goal. We aim to quantify the relation between blood eosinophils, exhaled nitric oxide (FeNO) and the risk of severe asthma attacks.

METHODS AND ANALYSIS

A systematic review of randomised controlled trials (RCTs) will be conducted by searching MEDLINE from January 1993 to April 2021. We will include RCTs that investigated the effect of fixed treatment(s) regimen(s) on severe asthma exacerbation rates over at least 24 weeks and reported a baseline value for blood eosinophils and FeNO. Study selection will follow the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, and the methodological appraisal of the studies will be assessed by the Cochrane Risk-of-Bias Tool for RCTs. Study authors will be contacted to request anonymised individual participant data (IPD) for patients randomised to the trial's control arm. An IPD meta-analysis will be performed for multivariable prognostic modelling with performance assessment (calibration plots and the c-statistic) in a cross-validation by study procedure. The outcome to predict is the absolute number of severe asthma attacks to occur in the following 12 months if anti-inflammatory therapy is not changed (ie, annualised number of attacks requiring ≥3 days of systemic corticosteroids and/or hospitalisation if the patient was randomised to the control arm of an RCT). A summary prognostic equation and risk stratification chart will be reported as a basis for further analyses of individualised treatment benefit.

ETHICS AND DISSEMINATION

The protocol has been reviewed by the relevant Oxford academic ethics committee and found to comprise fully anonymised data not requiring further ethical approbation. Results will be communicated in an international meeting and submitted to a peer-reviewed journal.

PROSPERO REGISTRATION NUMBER

CRD42021245337.

From DREAM to REALITI-A and beyond: Mepolizumab for the treatment of eosinophil-driven diseases

Effective treatment of inflammatory diseases is often challenging owing to their heterogeneous pathophysiology. Understanding of the underlying disease mechanisms is improving and it is now clear that eosinophils play a complex pathophysiological role in a broad range of type 2 inflammatory diseases. Standard of care for these conditions often still includes oral corticosteroids (OCS) and/or cytotoxic immune therapies, which are associated with debilitating side effects. Selective, biological eosinophil‐reducing agents provide treatment options that improve clinical symptoms associated with eosinophilic inflammation and reduce OCS use. Mepolizumab is a humanized monoclonal antibody that binds to and neutralizes interleukin‐5, the major cytokine involved in eosinophil proliferation, activation, and survival. Mepolizumab is approved for the treatment of severe eosinophilic asthma, eosinophilic granulomatosis with polyangiitis and hypereosinophilic syndrome. Additionally, the efficacy of add‐on mepolizumab has been observed in patients with severe chronic rhinosinusitis with nasal polyposis and chronic obstructive pulmonary disease with an eosinophilic phenotype. Here, we review the development, approval, and real‐world effectiveness of mepolizumab for the treatment of patients with severe eosinophilic asthma, from the DREAM to REALITI‐A studies, and describe how knowledge from this journey extended to the use of mepolizumab and other biologics across a broad spectrum of eosinophilic diseases.

Biomarkers to Predict Response to Inhaled Corticosteroids and Long-Acting Muscarinic Antagonists in Adolescents and Adults with Mild Persistent Asthma

Rationale: Whether biomarkers can be used to predict response to inhaled corticosteroids (ICS) or long-acting muscarinic antagonists (LAMA) in mild persistent asthma is unclear. Objectives: In a prespecified exploratory analysis of a randomized clinical trial of 295 participants 12 years of age or older with uncontrolled mild persistent asthma, we sought to identify biomarkers of treatment response after 12 weeks of ICS (mometasone, 200 μg or 220 μg twice/d), LAMA (tiotropium, 5 μg/d), or placebo in adults (⩾18 yr) and adolescents (12-17 yr) separately. Methods: The primary outcome was a composite outcome of asthma control (treatment failure, asthma control days, and forced expiratory volume in 1 second [FEV₁]). Analyses examined type 2 inflammatory biomarkers and physiologic biomarkers. We assessed the area under the receiver operating characteristic curve (AUC) for response to ICS and LAMA (each versus placebo). An AUC of 0.5 suggests no discrimination, 0.7-0.8 is considered acceptable, more than 0.8-0.9 is considered excellent, and more than 0.9 is considered outstanding. Results: In 237 adults, sputum and blood eosinophil levels and fractional exhaled nitric oxide (Fe_NO) each predicted ICS response (AUCs: 0.61 [95% confidence interval (CI), 0.53-0.69], 0.64 [95% CI, 0.56-0.72], and 0.62 [95% CI, 0.54-0.70], respectively; all P < 0.01); the AUC for blood eosinophil levels and Fe_NO together was 0.66 (95% CI, 0.58-0.74; P < 0.001). In 58 adolescents, the number of positive aeroallergens and total serum immunoglobulin E each predicted ICS response (AUCs: 0.69 [95% CI, 0.52-0.85] and 0.73 [95% CI, 0.58-0.87], respectively; both P < 0.03); the AUC for both together was 0.73 (95% CI, 0.58-0.87; P = 0.003). After ipratropium bromide, FEV₁ reversibility predicted LAMA response in adults (AUC: 0.61 [95% CI, 0.53-0.69], P = 0.007) but not in adolescents. Conclusions: The AUCs of the type 2 inflammatory biomarkers and physiological biomarkers we examined may not be high enough to confidently identify individuals with asthma who respond to ICS and LAMA. However, our findings indicate that the biomarkers that predict response to ICS or LAMA may differ in adults versus adolescents with uncontrolled mild persistent asthma. Prospective, biomarker-stratified clinical trials are needed to confirm these findings and to identify first-line controllers tailored for each population.

European Respiratory Society Guidelines for the Diagnosis of Asthma in Adults

Although asthma is very common affecting 5-10% of the population, the diagnosis of asthma in adults remains a challenge in the real world that results in both over- and under-diagnosis. A task force (TF) was set up by the European Respiratory Society to systematically review the literature on the diagnostic accuracy of tests used to diagnose asthma in adult patients and provide recommendation for clinical practice.The TF defined eight PICO (Population, Index, Comparator, and Outcome) questions that were assessed using the GRADE (Grading of Recommendations, Assessment, Development and Evaluation) approach, The TF utilised the outcomes to develop an evidenced-based diagnostic algorithm, with recommendations for a pragmatic guideline for everyday practice that was directed by real-life patient experiences.The TF support the initial use of spirometry followed, and if airway obstruction is present, by bronchodilator reversibility testing. If initial spirometry fails to show obstruction, further tests should be performed in the following order: FeNO, PEF variability or in secondary care, bronchial challenge. We present the thresholds for each test that are compatible with a diagnosis of asthma in the presence of current symptoms.The TF reinforce the priority to undertake spirometry and recognise the value of measuring blood eosinophils and serum IgE to phenotype the patient. Measuring gas trapping by body plethysmography in patients with preserved FEV1/FVC ratio deserves further attention. The TF draw attention on the difficulty of making a correct diagnosis in patients already receiving inhaled corticosteroids, the comorbidities that may obscure the diagnosis, the importance of phenotyping, and the necessity to consider the patient experience in the diagnostic process.

An independent in-depth analysis proposing adjusted Global Initiative on Asthma (GINA) Step 1-2 treatment suggestions

The Global initiative on asthma (GINA) strategy included major changes for the treatment of mild asthma in the 2020 version, that are even taken to a next level in 2021, leaving a preferred track with only rescue therapy with inhaled corticosteroid and formoterol (ICS-FORM) for step 1-2 in 12+ years-old. It has been questioned how solid the evidence behind these recommendations is. We decided to independently conduct an in-depth analysis of published evidence based on a comprehensive evaluation of original articles and related appendices and publications, including quality of evidence and risk-of-bias per article. We first defined the major asthma treatment goals and proceeded to review how these were met in publications referenced in the main asthma guidelines. For patients with GINA 2021 Step 1 characteristics the analysis supports GINA's decision to avoid SABA monotherapy and to prefer ICS-FORM rescue with as alternative ICS rescue every time a SABA is used for ≥12 years, even though evidence is extrapolated from step 2 patients. For 6-11 year-olds we propose to consider ICS-FORM rescue as an alternative, as its use has been approved in this age-group, be it not as rescue-medication. For patients with GINA 2021 Step 2 characteristics our proposal slightly differs from GINA 2021. We propose to continue avoiding the separate use of SABA, using ICS rescue whenever a fast-acting bronchodilator is taken (even with ICS maintenance). Also, the superiority of ICS-FORM rescue over classical step 2 treatment is not uniform and year-long experience is lacking. Consequently for now, both treatment options seem equal: ICS-FORM rescue or ICS maintenance with SABA (+ICS) rescue. For 6-11 year-olds ICS rescue every time a SABA is used has the advantage of lower total ICS dose; as alternative we suggest ICS-FORM rescue. The best treatment option depends on patient characteristics and treatment goals. Recommendations should be reviewed as soon as new evidence becomes available.

Blood eosinophils as a predictor of treatment response in adults with difficult-to-treat chronic cough

There is lack of evidence on the role of blood eosinophil count (BEC) as a predictor of treatment response in patients with chronic cough. The study aimed to evaluate BEC as a predictor of treatment response in all non-smoking adults with chronic cough and normal chest radiograph referred to cough clinic and in a subgroup of patients with chronic cough due to asthma or non-asthmatic eosinophilic bronchitis (NAEB).

This prospective cohort study included 142 consecutive, non-smoking patients referred to our cough centre due to chronic cough. The management of chronic cough was performed according to the current recommendations. At least a 30-mm decrease of 100-mm visual analogue scale in cough severity and a 1.3 points improvement in Leicester Cough Questionnaire were classified as a good therapeutic response.

There was a predominance of females (72.5%), median age 57.5 years with long-lasting, severe cough (median cough duration 60 months, severity 55/100 mm). Asthma and NAEB were diagnosed in 47.2% and 4.9% of patients, respectively. After 12–16 weeks of therapy, a good response to chronic cough treatment was found in 31.0% of all patients. A weak positive correlation was demonstrated between reduction in cough severity and BEC (r=0.28, p<0.001). Area under the curve for all patients with chronic cough was 0.62 with the optimal BEC cut-off for prediction of treatment response set at 237 cells·µL⁻¹ and for patients with chronic cough due to asthma/NAEB was 0.68 (95% CI 0.55–0.81) with the cut-off at 150 cells·µL⁻¹.

BEC is a poor predictor of treatment response in adults with chronic cough treated in the cough centre.

Evaluation of blood eosinophil count has limited value in prediction of therapeutic response in patients with difficult-to-treat chronic coughhttps://bit.ly/3EjaYsZ

The use of the mannitol test as an outcome measure in asthma intervention studies: a review and practical recommendations

BACKGROUND

The mannitol test is an indirect bronchial challenge test widely used in diagnosing asthma. Response to the mannitol test correlates with the level of eosinophilic and mast cell airway inflammation, and a positive mannitol test is highly predictive of a response to anti-inflammatory treatment with inhaled corticosteroids. The response to mannitol is a physiological biomarker that may, therefore, be used to assess the response to other anti-inflammatory treatments and may be of particular interest in early phase studies that require surrogate markers to predict a clinical response. The main objectives of this review were to assess the practical aspects of using mannitol as an endpoint in clinical trials and provide the clinical researcher and respiratory physician with recommendations when designing early clinical trials.

METHODS

The aim of this review was to summarise previous uses of the mannitol test as an outcome measure in clinical intervention studies. The PubMed database was searched using a combination of MeSH and keywords. Eligible studies included intervention or repeatability studies using the standard mannitol test, at multiple timepoints, reporting the use of PD₁₅ as a measure, and published in English.

RESULTS

Of the 193 papers identified, 12 studies met the inclusion criteria and data from these are discussed in detail. Data on the mode of action, correlation with airway inflammation, its diagnostic properties, and repeatability have been summarised, and suggestions for the reporting of test results provided. Worked examples of power calculations for dimensioning study populations are presented for different types of study designs. Finally, interpretation and reporting of the change in the response to the mannitol test are discussed.

CONCLUSIONS

The mechanistic and practical features of the mannitol test make it a useful marker of disease, not only in clinical diagnoses, but also as an outcome measure in intervention trials. Measuring airway hyperresponsiveness to mannitol provides a novel and reproducible test for assessing efficacy in intervention trials, and importantly, utilises a test that links directly to underlying drivers of disease.

Global Initiative for Asthma (GINA) Strategy 2021 - Executive summary and rationale for key changes

The Global Initiative for Asthma (GINA) Strategy Report provides clinicians with an annually updated evidence-based strategy for asthma management and prevention, which can be adapted for local circumstances (e.g., medication availability). This article summarizes key recommendations from GINA 2021, and the evidence underpinning recent changes. GINA recommends that asthma in adults and adolescents should not be treated solely with short-acting beta2-agonist (SABA), because of the risks of SABA-only treatment and SABA overuse, and evidence for benefit of inhaled corticosteroids (ICS). Large trials show that as-needed combination ICS-formoterol reduces severe exacerbations by ≥60% in mild asthma compared with SABA alone, with similar exacerbation, symptom, lung function and inflammatory outcomes as daily ICS plus as-needed SABA. Key changes in GINA 2021 include division of the treatment figure for adults and adolescents into two tracks. Track 1 (preferred) has low-dose ICS-formoterol as the reliever at all steps: as-needed only in Steps 1-2 (mild asthma), and with daily maintenance ICS-formoterol (maintenance-and-reliever therapy, MART) in Steps 3-5. Track 2 (alternative) has as-needed SABA across all steps, plus regular ICS (Step 2) or ICS-long-acting beta2-agonist (LABA) (Steps 3-5). For adults with moderate-to-severe asthma, GINA makes additional recommendations in Step 5 for add-on long-acting muscarinic antagonists and azithromycin, with add-on biologic therapies for severe asthma. For children 6-11 years, new treatment options are added at Steps 3-4. Across all age-groups and levels of severity, regular personalized assessment, treatment of modifiable risk factors, self-management education, skills training, appropriate medication adjustment and review remain essential to optimize asthma outcomes.

Global Initiative for Asthma (GINA) Strategy 2021 - Executive summary and rationale for key changes

The Global Initiative for Asthma (GINA) Strategy Report provides clinicians with an annually updated evidence-based strategy for asthma management and prevention, which can be adapted for local circumstances (e.g., medication availability). This article summarizes key recommendations from GINA 2021, and the evidence underpinning recent changes.GINA recommends that asthma in adults and adolescents should not be treated solely with short-acting beta2-agonist (SABA), because of the risks of SABA-only treatment and SABA overuse, and evidence for benefit of inhaled corticosteroids (ICS). Large trials show that as- needed combination ICS-formoterol reduces severe exacerbations by >60% in mild asthma compared with SABA alone, with similar exacerbation, symptom, lung function and inflammatory outcomes as daily ICS plus as-needed SABA.Key changes in GINA 2021 include division of the treatment figure for adults and adolescents into two tracks. Track 1 (preferred) has low-dose ICS-formoterol as the reliever at all steps: as-needed only in Steps 1-2 (mild asthma), and with daily maintenance ICS-formoterol (maintenance-and-reliever therapy, MART) in Steps 3-5. Track 2 (alternative) has as-needed SABA across all steps, plus regular ICS (Step 2) or ICS-long-acting beta2-agonist (LABA) (Steps 3-5). For adults with moderate-to-severe asthma, GINA makes additional recommendations in Step 5 for add-on long-acting muscarinic antagonists and azithromycin, with add-on biologic therapies for severe asthma. For children 6-11  years, new treatment options are added at Steps 3-4.Across all age-groups and levels of severity, regular personalized assessment, treatment of modifiable risk factors, self-management education, skills training, appropriate medication adjustment and review remain essential to optimize asthma outcomes.

Using FeNO Measurement in Clinical Asthma Management

Asthma is a common and heterogeneous disease, characterised by lower airway inflammation and airflow limitation. Critical factors in asthma management include establishing an accurate diagnosis and ensuring appropriate selection and dosage of anti-inflammatory therapies. The majority of asthma patients exhibit type 2 (T2) inflammation, with increased interleukin (IL)-4, IL-5, and IL-13 signalling, often with associated eosinophilia. Identifying lower airway eosinophilia with sputum induction improves asthma outcomes, but is time consuming and costly. Increased T2-inflammation leads to upregulation of nitric oxide (NO) release into the airway, with increasing fractional exhaled NO (FeNO) reflecting greater T2-inflammation. FeNO can be easily and quickly measured in the clinic, offering a point of care surrogate measure of the degree of lower airway inflammation. FeNO testing can be used to help confirm an asthma diagnosis, to guide inhaled corticosteroid therapy, to assess adherence to treatment, and to aid selection of appropriate biologic therapy. However, FeNO levels may also be influenced by a variety of intrinsic and extrinsic factors other than asthma, including nasal polyposis and cigarette smoking, and must be interpreted in the broader clinical context rather than viewed in isolation. This review discusses the clinical application of FeNO measurement in asthma care, from diagnosis to treatment selection, and describes its place in current international expert guidelines.

Global Initiative for Asthma (GINA) Strategy 2021 - Executive Summary and Rationale for Key Changes

The Global Initiative for Asthma (GINA) Strategy Report provides clinicians with an annually updated evidence-based strategy for asthma management and prevention, which can be adapted for local circumstances (e.g., medication availability). This article summarizes key recommendations from GINA 2021, and the evidence underpinning recent changes. GINA recommends that asthma in adults and adolescents should not be treated solely with short-acting beta2-agonist (SABA), because of the risks of SABA-only treatment and SABA overuse, and evidence for benefit of inhaled corticosteroids (ICS). Large trials show that as-needed combination ICS-formoterol reduces severe exacerbations by ≥60% in mild asthma compared with SABA alone, with similar exacerbation, symptom, lung function and inflammatory outcomes as daily ICS plus as-needed SABA. Key changes in GINA 2021 include division of the treatment figure for adults/adolescents into two tracks. Track 1 (preferred) has low-dose ICS-formoterol as the reliever at all steps: as-needed only in Steps 1-2 (mild asthma), and with daily maintenance ICS formoterol (maintenance-and-reliever therapy, MART) in Steps 3-5. Track 2 (alternative) has as-needed SABA across all steps, plus regular ICS (Step 2) or ICS-long-acting beta2-agonist (LABA) (Steps 3-5). For adults with moderate-to-severe asthma, GINA makes additional recommendations in Step 5 for add-on long-acting muscarinic antagonists and azithromycin, with add-on biologic therapies for severe asthma. For children 6-11 years, new treatment options are added at Steps 3-4. Across all age-groups and levels of severity, regular personalized assessment, treatment of modifiable risk factors, self-management education, skills training, appropriate medication adjustment and review remain essential to optimize asthma outcomes.

Serum 14-3-3β protein: a new biomarker in asthmatic patients with acute exacerbation in an observational study

Background

The determination of systemic inflammatory markers is one of the important directions to study the pathogenesis of asthma and improve the diagnosis of asthma. Current studies have found that the 14-3-3 protein family subtypes interact with target proteins to participate in the pathogenesis of a variety of immune inflammatory diseases. However, studies on serum tyrosine3-monooxygenase/tryptophan5-monooxygenase activation protein β (14-3-3β) in asthma are scarce. This study aimed to assess the clinical significance of 14-3-3β in asthmatic patients.

Methods

We recruited 54 asthmatic patients with acute exacerbation and 50 asthmatic patients with chronic persistent. The normal control group included 54 healthy individuals. Clinical characteristics, clinical indicators [fractional expiratory nitric oxide (FeNO), eosinophil count, forced vital capacity (FVC), percent of predicted FVC (FVC% predicted), forced expiratory volume in one second (FEV1), percent of predicted FEV1 (FEV1% predicted), the ratio of forced expiratory volume in one second to forced vital capacity (FEV1/FVC) and serum 14-3-3β levels were measured to compare among each group. Spearman’s rank correlation coefficient was used to evaluate the correlation between 14-3-3β and clinical indicators. Finally, Receiver-operating characteristic (ROC) curves analysis was used to determine the sensitivity and specificity of 14-3-3β.

Results

Our results showed that median (interquartile range) of serum 14-3-3β concentration (ng/mL) in acute exacerbation group of asthma (41.18 [33.06–51.76]) was much higher than that in normal control group (24.99 [17.43–29.91]; P < 0.001) and chronic persistent group of asthma (25.88 [21.03–34.55]; P < 0.001). Spearman’s correlation coefficient shows that the serum 14-3-3β level was positively correlated with FeNO (r = − 0.292, P = 0.032) and peripheral blood eosinophil count (r = 0.328, P = 0.016), and was negatively related to FEV1/FVC (r = − 0.293, P = 0.031) in the acute exacerbation group of asthma. At the same time, the serum 14-3-3β level was also negatively associated with FEV1 (r = − 0.297, P = 0.036) in the chronic persistent group of asthma. ROC curve analysis comparing acute exacerbation group of asthma with normal control group demonstrated a significant (P < 0.001) AUC of 0.90 (95% CI 0.85–0.96).

Conclusion

The serum 14-3-3β protein may become a potential biomarker in asthmatic patients with acute exacerbation.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13223-021-00608-4.