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

Clinical remission of mild-to-moderate asthma: Rates, contributing factors, and stability

Background

Although clinical remission (CR) of severe asthma has been extensively investigated, CR of mild-to-moderate asthma remains unexplored.

Objective

This study aimed to determine CR rates, contributing factors, and stability in patients with mild-to-moderate asthma.

Methods

We retrospectively analyzed 263 patients with asthma. Three-component CR was defined as no exacerbation, no daily oral corticosteroid receipt, and an Asthma Control Test score equivalent to that of the well control; 4-component CR included these parameters plus forced expiratory volume in 1 second of ≥80% predicted. CR during the 1 year and stability of CR over 10 years were retrospectively analyzed in patients with mild-to-moderate and severe asthma.

Results

The CR rates were significantly higher (4-component, 73.2%; 3-component, 81.0%) in patients with mild-to-moderate asthma compared with the CR rate in patients with severe asthma (4-component, 33.9%; and 3-component, 30.6%). A lower smoking index contributed to 3- and 4-component CR. Lower body mass index contributed to 3-component remission, and later onset and shorter asthma duration contributed to 4-component remission. In patients experiencing 4-component remission 10 years before, 80.3% maintained disease in remission; 89.1% of patients experiencing 3-component remission maintained disease in remission. In patients with disease that did not maintain 4-component CR after 10 years, predicted forced expiratory volume decreased, but no differences in inhaled corticosteroid and long-acting β-agonists/long-acting muscarinic antagonists receipt were detected between 10 years ago and the present. The current muscarinic antagonist receipt remained low, at 16.7%.

Conclusion

CR, including normalized forced expiratory volume, is obtainable and sustainable in most Japanese patients with mild-to-moderate asthma. Assessing CR in these patients may help avoid undertreatment and reduce future risks.

Guidance for type 2 inflammatory biomarkers

Type 2 inflammation in the airways and lungs is inflammation induced by type 2 cytokines such as IL-4, IL-5, and IL-13, produced primarily by type 2 helper T cells and type 2 innate lymphoid cells, and causes changes in the physiology and structure of the airways. Type 2 inflammation is currently in the spotlight because of its direct link to the treatment of several airway and lung diseases. Abundant evidences have accumulated that inflammatory biomarkers such as blood eosinophils, fractional exhaled nitric oxide, and IgE are essential clinical tools in the diagnosis and management of asthma and COPD. It is well known that asthma and COPD have diverse inflammatory phenotypes even when clinical features are similar, and it has been demonstrated that assessment of airway inflammation with biomarkers can improve diagnostic accuracy, determine safer and more effective treatment strategies, and predict future risks such as exacerbations and lung function decline. The Japanese Respiratory Society has published clinical practice guidelines for the evaluation of type 2 inflammation in the airways and lungs. In addition to asthma and COPD, the guide covers a wide range of airway and lung diseases, including interstitial lung disease, allergic bronchopulmonary mycosis, allergic rhinitis, and eosinophilic chronic rhinosinusitis. It also provides comprehensive guidelines covering a variety of clinical biomarkers. The purpose of this guidance is to provide evidences for the interpretation of type 2 inflammation measurements and to promote the widespread use of inflammation assessment to further improve the efficiency of airway and respiratory disease management.

Association Between MUC13 Gene Polymorphisms and Exacerbations of Asthma Under the Influence of Cigarette Smoking

Acute exacerbation of asthma is often characterized by increased mucus production and hypersecretion. While mucins are believed to play a role in the pathogenesis and pathophysiology of airway diseases, no genetic studies on mucin genes have been conducted to date. We initially analyzed a genome-wide association dataset of 608 asthmatics, focusing on mucin gene polymorphisms. Subsequently, we conducted fine genotyping of the MUC13 gene in a separate cohort of 704 bronchial asthma patients monitored for over a year. Using generalized linear models and multiple logistic regression analyses, we evaluated the genetic associations of single nucleotide polymorphisms (SNPs) with the frequency of annual exacerbations and the likelihood of frequent exacerbations. Among 105 SNPs in 14 mucin genes analyzed, rs6765247 in MUC13 showed the most significant association with annual asthma exacerbation frequency. Fine genotyping revealed that individuals homozygous for the minor allele of rs6765247T>G had significantly more annual exacerbations compared to those with the common allele (mean ± SD; 0.94 ± 1.73 vs. 0.43 ± 1.02 and 0.35 ± 0.79, p = 0.001). The frequency of minor allele homozygotes was 3.2 times higher in frequent exacerbators than in nonfrequent exacerbators. The associations were particularly significant in smokers (interaction p = 0.009). These findings indicate that MUC13 is important in exacerbating asthma due to smoking and could be used as a marker to predict frequent exacerbations in smokers.

Mitochondrial DNA copy number variation in asthma risk, severity, and exacerbations

BACKGROUND

Asthma pathophysiology is associated with mitochondrial dysfunction. Mitochondrial DNA copy number (mtDNA-CN) has been used as a proxy of mitochondrial function, with lower levels indicating mitochondrial dysfunction in population studies of cardiovascular diseases and cancers.

OBJECTIVES

We investigated whether lower levels of mtDNA-CN are associated with asthma diagnosis, severity, and exacerbations.

METHODS

mtDNA-CN is evaluated in blood from 2 cohorts: UK Biobank (UKB) (asthma, n = 39,147; no asthma, n = 302,302) and Severe Asthma Research Program (SARP) (asthma, n = 1283; nonsevere asthma, n = 703).

RESULTS

Individuals with asthma have lower mtDNA-CN compared to individuals without asthma in UKB (beta, -0.006 [95% confidence interval, -0.008 to -0.003], P = 6.23 × 10-6). Lower mtDNA-CN is associated with asthma prevalence, but not severity in UKB or SARP. mtDNA-CN declines with age but is lower in individuals with asthma than in individuals without asthma at all ages. In a 1-year longitudinal study in SARP, mtDNA-CN was associated with risk of exacerbation; those with highest mtDNA-CN had the lowest risk of exacerbation (odds ratio 0.333 [95% confidence interval, 0.173 to 0.542], P = .001). Biomarkers of inflammation and oxidative stress are higher in individuals with asthma than without asthma, but the lower mtDNA-CN in asthma is independent of general inflammation or oxidative stress. Mendelian randomization studies suggest a potential causal relationship between asthma-associated genetic variants and mtDNA-CN.

CONCLUSION

mtDNA-CN is lower in asthma than in no asthma and is associated with exacerbations. Low mtDNA-CN in asthma is not mediated through inflammation but is associated with a genetic predisposition to asthma.

Durability of benralizumab effectiveness in severe eosinophilic asthma patients with and without chronic rhinosinusitis with nasal polyps: a post hoc analysis from the ANANKE study

Introduction

Severe eosinophilic asthma (SEA) often co-occurs with chronic rhinosinusitis with nasal polyps (CRSwNP), worsening asthma symptoms. Earlier studies have shown that benralizumab improves asthma outcomes with greater efficacy if patients present CRSwNP.

Methods

This post hoc analysis of the ANANKE study (NCT04272463) reports data on the long-term effectiveness of benralizumab between SEA patients with and without CRSwNP (N = 86 and N = 75, respectively) treated for up to 96 weeks.

Results

Before benralizumab initiation, CRSwNP patients displayed longer SEA duration, greater oral corticosteroid (OCS) use and blood eosinophil count. After 96 weeks of treatment, the annual exacerbation rate (AER) decreased in both groups, with CRSwNP patients achieving considerable reductions than No-CRSwNP patients (severe AER dropped by 100% and 95.6%, respectively). While lung function improvement was comparable at week 96, CRSwNP patients showed a faster response to benralizumab, with a rise of forced expiratory volume in 1 s (FEV1) at 16 weeks that was maintained throughout the study. Median OCS daily dose decreased to 0.0 mg in both groups at 96 weeks, but benralizumab OCS-sparing effect was faster in CRSwNP patients (median OCS dose was 0.0 mg and 2.5 mg in CRSwNP and No-CRSwNP patients respectively, at 48 weeks). Although asthma control test (ACT) median scores were comparable, greater proportions of CRSwNP patients displayed well-controlled asthma (ACT ≥ 20) than No-CRSwNP patients at all time points.

Discussion

These findings show benralizumab long-term effectiveness in SEA patients with and without CRSwNP, highlighting its superior and faster-acting benefits on asthma outcomes in presence of CRSwNP.

Trajectory of the response to bronchodilator and respiratory outcomes in adults with asthma-like symptoms

In the real world, health professionals need to care for individuals with asthma-like symptoms who have a persistently negative bronchodilator response (BDR). Little is known about the evolution of symptoms and lung function of these individuals because they are usually excluded from studies on asthma. The aim of this study was to evaluate whether individuals with asthma-like symptoms but with a persistently negative BDR have a different evolution of symptoms and lung function compared to individuals with asthma proven by positive BDR. This prospective cohort study included adults with asthma-like symptoms. Individuals participated in two visits 12 months apart. They responded to questionnaires and underwent a spirometry test. In individuals without airway obstruction in the first visit, those with asthma-like symptoms and persistently negative BDR were less likely to lose forced expiratory volume in the first second during follow-up or progress to airway obstruction at the final visit compared to individuals with asthma proven by positive BDR. Among individuals with airway obstruction at baseline, those with asthma-like symptoms and persistently negative BDR were less likely to resolve the airway obstruction during follow-up compared to individuals with asthma proven by positive BDR. In individuals with proven asthma, the emergence or persistence of positive BDR during follow-up was accompanied by a worsening of asthma outcomes compared to the remission of positive BDR. Thus, BRD is an accessible marker of disease progression in individuals with asthma-like symptoms. In individuals with asthma proven by positive BDR, the trend in BDR was associated with the evolution of symptoms and lung function.

Asthma Exacerbation Risk in Pregnancy and Postpartum: Assessing the Impact of Gestational Diabetes Mellitus and Other Key Factors

BACKGROUND

Asthma, affecting approximately 13% of pregnancies worldwide, and gestational diabetes mellitus (GDM), present in approximately 14%, are both associated with adverse maternal and perinatal outcomes. This study aims to address a lack of current knowledge about how GDM affects asthma during pregnancy.

OBJECTIVE

To determine whether GDM is associated with an increased risk of asthma exacerbations during pregnancy and the first year postpartum.

METHODS

This retrospective cohort study analyzed electronic health records of pregnant patients with asthma from 2010 to 2023, excluding those with pre-existing diabetes mellitus or concurrent chronic lung diseases. Asthma exacerbations were defined by the need for an oral corticosteroid prescription. Multivariable logistic regression and zero-inflated Poisson regression were used to adjust for age, race, body mass index (BMI), prepregnancy asthma exacerbation history, and insurance status.

RESULTS

Among 10,985 individuals, 1492 had GDM. Patients with GDM were older with higher BMIs. GDM was associated with increased asthma exacerbation risk during pregnancy (adjusted odds ratio [OR] = 1.36, 95% confidence interval [CI]: 1.10-1.67), but not postpartum. Stratified analyses of 4331 individuals with gestational blood glucose measurement showed that each doubling of blood glucose levels doubled the risk of asthma exacerbations during pregnancy (adjusted OR = 2.02, 95% CI: 1.45-2.81). Other factors associated with asthma exacerbation included prepregnancy asthma exacerbations, older age, and Medicaid coverage.

CONCLUSION

The association between GDM and increased risk of asthma exacerbations underscores the need for early, universal screening and effective interventions to improve blood glucose control in pregnant individuals with pre-existing asthma.

T1-T2 Interplay in the Complex Immune Landscape of Severe Asthma

Asthma is orchestrated by an aberrant immune response involving a complex interplay between multiple inflammatory cell types. An increase in Th2 cells in the asthmatic airway is a hallmark of asthma, and biologics blocking their effector functions have been life-changing for many severe asthma patients who poorly respond to immunosuppression by corticosteroids. However, studies in the past decade have highlighted not only other cell types that also produce Th2 cytokines boosting the Type 2/T2 phenotype but also a heightened IFN-γ response, primarily from T cells, referred to as a Type 1/T1 immune response. Data derived from studies of immune cells in the airways and mouse models of severe asthma suggest a role of IFN-γ in corticosteroid resistance, airway hyperreactivity, and also airway remodeling via effects on other cell types including mast cells, eosinophils, airway epithelial cells, and airway smooth muscle cells. The simultaneous presence of T1 and T2 immune responses is detectable in the sickest of asthma patients in whom corticosteroids suppress the T2 but not the T1 response. This article has reviewed our current understanding of the complex T1-T2 interplay in severe asthma highlighting mediators that impact both arms which may be targeted alone or in combination for disease alleviation.

Chronic rhinosinusitis and asthma: epidemiology, pathophysiology, morbidity, treatment

PURPOSE OF REVIEW

Especially with the advent of biologics which have originally been prescribed primarily for pulmonary disease, the interconnections between asthma and chronic rhinosinusitis are becoming even more apparent. Biologics can now also be prescribed for chronic rhinosinusitis in some countries. But what is the epidemiology, pathophysiology and treatment of both diseases?

RECENT FINDINGS

This review covers the epidemiology, pathophysiology, morbidity and treatment of both diseases. Specifically, this review highlights the interdependencies of both diseases and potential future treatment options.

SUMMARY

This review aims to alert physicians to go beyond treating only one of the diseases, but rather to get a broader picture of the diseases and treatment options.

A RESPONSE to antiIL-5 therapy in comorbid patients with chronic rhinosinusitis with nasal polyps and severe asthma: Study protocol

Background

Chronic rhinosinusitis with nasal polyps (CRSwNP) and severe asthma (SA) are 2 frequently coexisting conditions that are, in most cases, associated with eosinophilic inflammation. The concurrence of both diseases has a negative synergistic impact on disease severity and patients' health-related quality of life. Thus, a holistic, collaborative management of these patients is a critical unmet need. Mepolizumab, a systemic anti-IL-5 therapy, has been shown to be effective as an add-on treatment in both SA and CRSwNP, with more literature available on asthma outcomes than on CRSwNP.

Objectives

The primary objective of the study is to evaluate the real-world effectiveness of mepolizumab in improving the health-related quality of life of comorbid patients at 12 months using the SNOT-22 questionnaire. Secondary objectives include safety and efficacy outcomes of mepolizumab treatment in the 2 populations, which are expected to have variable severity of the respective comorbid conditions.

Methods

RESPONSE is a European real-world prospective cohort study designed to assess the effectiveness of mepolizumab in 2 cohorts of adult patients: one with SA as primary diagnosis with (secondary diagnosis) comorbid CRSwNP, and another with CRSwNP as primary diagnosis with (secondary diagnosis) comorbid asthma. Up to 350 patients receiving newly prescribed mepolizumab will be followed up for 12 months as per the investigators' standard of care.

Conclusion

This study will report the effects of anti-IL-5 therapy in both diseases investigated and the respective comorbidity, as well as the consequence of treating milder forms of asthma and CRSwNP with mepolizumab, supporting the emerging evidence on early treatment optimization.

Possible Involvement of Lysophospholipids in Severe Asthma as Novel Lipid Mediators

In severe asthma, symptoms are unstable despite intensive treatment based on high doses of inhaled corticosteroids and on-demand use of oral corticosteroids. Although, recently, various biological agents related to Th2 cytokines have been added to intensive controller medications for severe asthma, a significant progress has not been observed in the management for symptoms (dyspnea, wheezing and cough). Medical treatment focused on Type 2 inflammation is probably insufficient to maintain good long-term management for severe asthma. Airway eosinophilia and decreased reversibility in forced expiratory volume in 1 second (FEV1) are listed as major predictors for exacerbation-prone asthma. However, it is generally considered that asthma is complex and heterogeneous. It is necessary to establish precision medicine using treatable traits based on a multidimensional approach related to asthma. Since phospholipids generate lysophospholipids and arachidonic acid by phospholipases, lysophospholipids can be associated with the pathogenesis of this disease via action on smooth muscle, endothelium, and epithelium in the airways. Lysophosphatidic acid (LPA), lysophosphatidylcholine (LPC), and sphingosine 1-phosphate (S1P) are increased in bronchoalveolar fluid after allergen challenge. LPA, LPC, and S1P recruit eosinophils to the lungs and cause β2-adrenergic desensitization. LAP and S1P cause contraction and hyperresponsiveness in airway smooth muscle. Moreover, lysophosphatidylserine and S1P are associated with the allergic reaction related to IgE/FcεRI in mast cells. Lysophospholipid action is probably comprised of corticosteroid resistance and is independent of Type 2 inflammation, and may be corelated with oxidative stress. Lysophospholipids may be a novel molecular target in advancing the management and treatment of asthma. This review discusses the clinical relevance of lysophospholipids in asthma.

Real-world mepolizumab treatment in patients with severe asthma decreased exacerbations, oral corticosteroid use, and healthcare resource utilization and costs over 4 years: a retrospective analysis

OBJECTIVE

Although the efficacy of mepolizumab in reducing exacerbations and oral corticosteroid (OCS) use in severe asthma is well-established, real-world long-term effectiveness data are limited. This study evaluated the real-world impact of mepolizumab treatment in patients with severe asthma over a 4-year follow-up period.

METHODS

This was a retrospective cohort study of patients with asthma initiating mepolizumab (index date: first claim, November 2015-September 2019) using the Merative MarketScan Commercial and Medicare Databases. Outcomes included asthma exacerbations, OCS use, and exacerbation-related healthcare resource utilization (HCRU) and costs, assessed 12-months pre-index (baseline) and annually during the 4-year follow-up period.

RESULTS

Among 189 eligible patients, mean asthma exacerbation rate (AER) declined progressively from baseline during follow-up: AER decreased by 53.8% at Year 1 and 73.8% by Year 4 (p < 0.001). The annual OCS prescription rate reduced from baseline by 41.1% at Year 1 and 62.2% at Year 4 (p < 0.001). The proportion of patients with both no exacerbations and no OCS use progressively increased from 6.4% at baseline to 18.5% at Year 1 and 41.8% at Year 4. Exacerbation-related HCRU including inpatient, emergency room, and outpatient office visits decreased from baseline (9.0%, 21.7%, and 78.8%, respectively), at Year 1 (3.2%, 12.2%, and 49.2%), and Year 4 (0.0%, 4.8%, and 31.8%). Exacerbation-related healthcare costs declined from $4,635 at baseline to $1,487 at Year 1 and $217 at Year 4 (p < 0.001).

CONCLUSION

Patients treated with mepolizumab demonstrated progressive and sustained long-term, real-world reductions in exacerbation frequency, OCS dependency, and exacerbation-related HCRU and costs over 4 years.

Non-Pharmaceutical Interventions May Attenuate Acute Exacerbations of Asthma: Experience During the COVID-19 Pandemic in Taiwan

Background

Non-pharmaceutical interventions (NPIs) were widely used during the coronavirus disease 2019 (COVID-19) pandemic, however their impact on acute asthma exacerbations (AEs) is not well studied.

Methods

We had retrospectively collected patients with asthma AEs between 2019 and 2020 and retrieved data from the Chang Gung Research Database, including clinical manifestations, medications, pulmonary function, clinic and emergency department visits and hospitalizations.

Results

A total of 39,108 adult patients with asthma were enrolled, of whom 1502 were eligible for analysis. The prevalence of acute AEs significantly decreased throughout 2020 compared with 2019 after implementation of the NPI policy. The patients were categorized into four groups: Group 1, acute AEs in 2019 with influenza infection (n=692); Group 2: acute AEs in 2019 without influenza infection (n=328); Group 3: acute AEs in 2020 with influenza infection (n=268); Group 4: acute AEs in 2020 without influenza infection (n=214). The patients in group 4 were significantly older (73.3±29.1 vs 65.5±29.2, 69.7±26.2 years, p<0.01) and had significantly worse forced expiratory volume in one second/forced vital capacity ratio (70.5±13.9 vs 79.6±15.5, 72.9±18.0, p<0.01) than those in group 1 and 2, and the highest rate of oral corticosteroid prescriptions (17%, p<0.01). The patients in group 3 and 4 had significantly lower rates of oxygen therapy, ventilator use and mortality at 3 and 12 months of follow-up than those in group 1 and 2.

Conclusion

The use of NPIs during the COVID-19 pandemic in Taiwan may reduce the frequency and severity of asthma AEs. This may provide some cost-effective strategies to attenuate acute asthma AEs.

Development of an asthma health-care burden score as a measure of severity and predictor of remission in SARP III and U-BIOPRED: results from two major longitudinal asthma cohorts

BACKGROUND

Current asthma guidelines, including those of the European Respiratory Society (ERS) and American Thoracic Society (ATS), suboptimally predict asthma remission, disease severity, and health-care utilisation. We aimed to establish a novel approach to assess asthma severity based on asthma health-care burden data.

METHODS

We analysed prospectively collected data from the Severe Asthma Research Program III (SARP III; USA) and the European Unbiased Biomarkers for the Prediction of Respiratory Disease Outcomes (U-BIOPRED; 11 European countries) to calculate a composite burden score based on asthma exacerbations and health-care utilisation, which was modified to include the use of short-acting beta agonists (SABAs) to reflect asthma symptom burden.

FINDINGS

In SARP III, 528 adult participants with asthma were followed up for a mean of 4·4 (SD 1·6) years, and 312 (59%) had severe asthma according to the ERS-ATS definition. Among the 205 participants with asthma who used rescue SABAs daily, 90 used these two or more times a day. In U-BIOPRED, 509 adult participants with asthma were followed up for 1 year, and 421 (83%) had severe asthma. The burden score was less than 1·29 per patient-year in 106 (34%) of 312 SARP III participants and in 80 (19%) of 421 U-BIOPRED participants with severe asthma. By contrast, the burden score was above the median value in 58 (28%) SARP III and 24 (27%) U-BIOPRED participants with non-severe asthma. In both cohorts, the burden score negatively correlated with lung function, asthma control, and quality of life. A burden score of 0·15 or lower predicted asthma remission with a sensitivity greater than 91% and a specificity of 99%.

INTERPRETATION

Our findings highlight considerable discrepancies between the current definition of asthma severity and our burden score. Although the definition of severe asthma proposed by the ERS-ATS and the and Global Initiative for Asthma (GINA) is based on prescribed asthma medications, our personalised health-care burden score includes patient-centred data that reflect disease severity and accurately predicts asthma remission. Subject to prospective validation, the burden score could help to optimise the management of high-risk individuals with asthma.

FUNDING

SARP III: US National Heart, Lung, and Blood Institute; AstraZeneca; Boehringer Ingelheim; Genentech; GlaxoSmithKline; Sanofi Genzyme/Regeneron; and Teva Pharmaceuticals.

U-BIOPRED

Innovative Medicines Initiative Joint Undertaking (EU's Seventh Framework Programme and European Federation of Pharmaceutical Industries and Associations) and eTRIKS project.

Upper airway comorbidities of asthma

Asthma, characterized as a chronic heterogeneous airway disease, often presents with common comorbid conditions. The concept of "one airway, one disease" was coined more than 20 years ago, emphasizing the connection between asthma and upper airway comorbidities (UACs) such as allergic or nonallergic rhinitis, chronic rhinosinusitis with or without nasal polyps, and aspirin/nonsteroidal anti-inflammatory drug-exacerbated respiratory disease. Since then, numerous studies have demonstrated that UACs are closely related and affect asthma phenotypes. Recognizing these UACs and managing them are crucial aspects of comprehensive asthma care. Addressing these conditions as part of asthma treatment can lead to better control of symptoms, improved lung function, and better quality of life. Moreover, it is important to explore the field of respiratory biologics, which represents the latest advancements in medical treatment options for patients with asthma and UACs.

Obesity and hormonal influences on asthma: Mechanisms, management challenges, and emerging therapeutic strategies

Obesity and hormone dysregulation, common comorbidities of asthma, not only influence asthma risk and onset but can also complicate its management. The pathobiologic characteristics of obesity, such as insulin resistance and metabolism alterations, can impact lung function and airway inflammation while highlighting potential opportunities for therapeutic intervention. Likewise, obesity alters immune cell phenotypes and corticosteroid pharmacokinetics. Hormones such as sex hormones, incretins, and thyroid hormones can also affect asthma. This review highlights the mechanisms underlying obesity-related asthma and hormonal pathologies while exploring potential therapeutic strategies and the need for more research and innovative approaches in managing these comorbid conditions.

Asthma exacerbations and airway redox imbalance under type 2 inflammatory conditions

Asthma is a chronic inflammatory airway disease characterized by bronchial hyperresponsiveness and reversibility. Despite considerable advances in asthma treatment based on our understanding of its pathophysiology, asthma exacerbations remain challenging. To reduce asthma exacerbations, it is essential to identify triggers, patients' risk factors, and underlying mechanisms. While exposure to viruses and environmental stimuli are known common triggers for asthma exacerbations, the key factors involved in asthma exacerbations have been identified as type 2 inflammation. Type 2 inflammatory biomarkers have been demonstrated to be useful in predicting individuals at risk of exacerbations. Furthermore, recent clinical trials of targeted biological therapy, which blocks the type 2 pathway, have supported the critical role of type 2 inflammation in asthma exacerbations. Although the specific mechanisms linking type 2 inflammation to asthma exacerbations have not yet been fully elucidated, increasing evidence shows that reduction/oxidation (redox) imbalance likely plays an important role in this association. Under type 2 inflammatory conditions, human airway epithelial cells activate 15-lipoxygenase-1 in complex with phosphatidylethanolamine binding protein-1, leading to the generation of electrophilic hydroperoxyl-phospholipids. When the accumulation of reactive lipid peroxidation surpasses a specific glutathione-dependent activity, these electrophilic compounds are not neutralized, leading to programmed cell death, ferroptosis. Reduced glutathione levels, caused by type 2 inflammation, may impair its ability to neutralize reactive lipid peroxidation. The accumulation of lipid peroxidation with intracellular redox imbalance may contribute to asthma exacerbations in individuals with type 2 inflammation. Inhibiting the ferroptotic pathway holds promise as a therapeutic strategy to alleviate asthma exacerbations.

Immunologic aspects of asthma: from molecular mechanisms to disease pathophysiology and clinical translation

In the present review, we focused on recent translational and clinical discoveries in asthma immunology, facilitating phenotyping and stratified or personalized interventions for patients with this condition. The immune processes behind chronic inflammation in asthma exhibit marked heterogeneity, with diverse phenotypes defining discernible features and endotypes illuminating the underlying molecular mechanisms. In particular, two primary endotypes of asthma have been identified: "type 2-high," characterized by increased eosinophil levels in the airways and sputum of patients, and "type 2-low," distinguished by increased neutrophils or a pauci-granulocytic profile. Our review encompasses significant advances in both innate and adaptive immunities, with emphasis on the key cellular and molecular mediators, and delves into innovative biological and targeted therapies for all the asthma endotypes. Recognizing that the immunopathology of asthma is dynamic and continuous, exhibiting spatial and temporal variabilities, is the central theme of this review. This complexity is underscored through the innumerable interactions involved, rather than being driven by a single predominant factor. Integrated efforts to improve our understanding of the pathophysiological characteristics of asthma indicate a trend toward an approach based on disease biology, encompassing the combined examination of the clinical, cellular, and molecular dimensions of the disease to more accurately correlate clinical traits with specific disease mechanisms.

State of the art: Alternative overlap syndrome-asthma and obstructive sleep apnea

In the general population, Bronchial Asthma (BA) and Obstructive Sleep Apnea (OSA) are among the most prevalent chronic respiratory disorders. Significant epidemiologic connections and complex pathogenetic pathways link these disorders via complex interactions at genetic, epigenetic, and environmental levels. The coexistence of BA and OSA in an individual likely represents a distinct syndrome, that is, a collection of clinical manifestations attributable to several mechanisms and pathobiological signatures. To avoid terminological confusion, this association has been named alternative overlap syndrome (vs overlap syndrome represented by the chronic obstructive pulmonary disease-OSA association). This comprehensive review summarizes the complex, often bidirectional links between the constituents of the alternative overlap syndrome. Cross-sectional, population, or clinic-based studies are unlikely to elucidate causality or directionality in these relationships. Even longitudinal epidemiological evaluations in BA cohorts developing over time OSA, or OSA cohorts developing BA during follow-up cannot exclude time factors or causal influence of other known or unknown mediators. As such, a lot of pathophysiological interactions described here have suggestive evidence, biological plausibility, potential or actual directionality. By showcasing existing evidence and current knowledge gaps, the hope is that deliberate, focused, and collaborative efforts in the near-future will be geared toward opportunities to shine light on the unknowns and accelerate discovery in this field of health, clinical care, education, research, and scholarly endeavors.

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.

Novel insights into the pleiotropic health effects of growth differentiation factor 11 gained from genome-wide association studies in population biobanks

BACKGROUND

Growth differentiation factor 11 (GDF11) is a member of the transforming growth factor-β (TGF-β) superfamily that has gained considerable attention over the last decade for its observed ability to reverse age-related deterioration of multiple tissues, including the heart. Yet as many researchers have struggled to confirm the cardioprotective and anti-aging effects of GDF11, the topic has grown increasingly controversial, and the field has reached an impasse. We postulated that a clearer understanding of GDF11 could be gained by investigating its health effects at the population level.

METHODS AND RESULTS

We employed a comprehensive strategy to interrogate results from genome-wide association studies in population Biobanks. Interestingly, phenome-wide association studies (PheWAS) of GDF11 tissue-specific cis-eQTLs revealed associations with asthma, immune function, lung function, and thyroid phenotypes. Furthermore, PheWAS of GDF11 genetic variants confirmed these results, revealing similar associations with asthma, immune function, lung function, and thyroid health. To complement these findings, we mined results from transcriptome-wide association studies, which uncovered associations between predicted tissue-specific GDF11 expression and the same health effects identified from PheWAS analyses.

CONCLUSIONS

In this study, we report novel relationships between GDF11 and disease, namely asthma and hypothyroidism, in contrast to its formerly assumed role as a rejuvenating factor in basic aging and cardiovascular health. We propose that these associations are mediated through the involvement of GDF11 in inflammatory signaling pathways. Taken together, these findings provide new insights into the health effects of GDF11 at the population level and warrant future studies investigating the role of GDF11 in these specific health conditions.

Investigation of lactotransferrin messenger RNA expression levels as an anti-type 2 asthma biomarker

BACKGROUND

Lactotransferrin (LTF) has an immunomodulatory function, and its expression levels are associated with asthma susceptibility.

OBJECTIVES

We sought to investigate LTF messenger RNA (mRNA) expression levels in human bronchial epithelial cells (BECs) as an anti-type 2 (T2) asthma biomarker.

METHODS

Association analyses between LTF mRNA expression levels in BECs and asthma-related phenotypes were performed in the Severe Asthma Research Program (SARP) cross-sectional (n = 155) and longitudinal (n = 156) cohorts using a generalized linear model. Correlation analyses of mRNA expression levels between LTF and all other genes were performed by Spearman correlation.

RESULTS

Low LTF mRNA expression levels were associated with asthma susceptibility and severity (P < .025), retrospective and prospective asthma exacerbations, and low lung function (P < 8.3 × 10-3). Low LTF mRNA expression levels were associated with high airway T2 inflammation biomarkers (sputum eosinophils and fractional exhaled nitric oxide; P < 8.3 × 10-3) but were not associated with blood eosinophils or total serum IgE. LTF mRNA expression levels were negatively correlated with expression levels of TH2 or asthma-associated genes (POSTN, NOS2, and MUC5AC) and eosinophil-related genes (IL1RL1, CCL26, and IKZF2) and positively correlated with expression levels of TH1 and inflammation genes (IL12A, MUC5B, and CC16) and TH17-driven cytokines or chemokines for neutrophils (CXCL1, CXCL6, and CSF3) (P < 3.5 × 10-6).

CONCLUSIONS

Low LTF mRNA expression levels in BECs are associated with asthma susceptibility, severity, and exacerbations through upregulation of airway T2 inflammation. LTF is a potential anti-T2 biomarker, and its expression levels may help determine the balance of eosinophilic and neutrophilic asthma.

Comorbid allergy and rhinitis and patient-related outcomes in asthma and COPD: a cross-sectional study

Introduction

The study aimed to compare prevalence of comorbid allergic manifestations and rhinitis, allergy testing and associations with patient-related outcomes in patients with asthma and COPD.

Methods

Cross-sectional study of randomly selected Swedish patients with a doctor's diagnosis of asthma (n = 1291) or COPD (n = 1329). Self-completion questionnaires from 2014 provided data on demographics, rhinitis, allergic symptoms at exposure to pollen or furry pets, exacerbations, self-assessed severity of disease and scores from the Asthma Control Test (ACT) and the COPD Assessment Test (CAT), and records were reviewed for allergy tests.

Results

Allergic manifestations were more common in asthma (75%) compared with COPD (38%). Rhinitis was reported in 70% of asthma and 58% of COPD patients. Allergy tests had been performed during the previous decade in 28% of patients with asthma and in 8% of patients with COPD.In patients with asthma; comorbid allergy and rhinitis were both independently associated with increased risk for poor asthma symptom control (ACT < 20) (OR [95% CI] 1.41 [1.05 to 1.87] and 2.13 [1.60 to 2.83]), exacerbations (1.58 [1.15 to 2.17] and 1.38 [1.02 to 1.86]), and self-assessed moderate/severe disease (1.64 [1.22 to 2.18] and 1.75 [1.33 to 2.30]). In patients with COPD, comorbid allergy and rhinitis were both independently associated with increased risk for low health status (CAT ≥ 10) (OR [95% CI] 1.46 [1.20 to 1.95] and 2.59 [1.97 to 3.41]) respectively, with exacerbations during the previous six months (1.91 [1.49 to 2.45] and 1.57 [1.23 to 2.01]), and with self-assessed moderate/severe disease (1.70 [1.31 to 2.22] and 2.13 [1.66 to 2.74]).

Conclusion

Allergic manifestations and rhinitis are more common in asthma than COPD but associated with worse outcomes in both diseases. This highlights the importance of examining and treating comorbid allergy and rhinitis, not only in asthma but also in COPD.

The impact of diabetes mellitus on blood-tissue barrier regulation and vascular complications: Is the lung different from other organs?

Diabetes Mellitus presents a formidable challenge as one of the most prevalent and complex chronic diseases, exerting significant strain on both patients and the world economy. It is recognized as a common comorbidity among severely ill individuals, often leading to a myriad of micro- and macro-vascular complications. Despite extensive research dissecting the pathophysiology and molecular mechanisms underlying vascular complications of diabetes, relatively little attention has been paid to potential lung-related complications. This review aims to illuminate the impact of diabetes on prevalent respiratory diseases, including chronic obstructive pulmonary disease (COPD), acute respiratory distress syndrome (ARDS), idiopathic pulmonary fibrosis (IPF), tuberculosis (TB), pneumonia infections, and asthma, and compare the vascular complications with other vascular beds. Additionally, we explore the primary mechanistic pathways contributing to these complications, such as the expression modulation of blood-tissue-barrier proteins, resulting in increased paracellular and transcellular permeability, and compromised immune responses rendering diabetes patients more susceptible to infections. The activation of inflammatory pathways leading to cellular injury and hastening the onset of these respiratory complications is also discussed.

Efficacy of Tezepelumab in Patients with Severe, Uncontrolled Asthma Across Multiple Clinically Relevant Subgroups in the NAVIGATOR Study

INTRODUCTION

Many patients with severe asthma continue to experience symptoms and exacerbations despite treatment with standard-of-care therapy. In the phase 3 NAVIGATOR study, tezepelumab significantly reduced exacerbations over 52 weeks compared with placebo in patients with severe, uncontrolled asthma. This analysis assessed the efficacy of tezepelumab in reducing asthma exacerbations in various clinically relevant subgroups of patients in NAVIGATOR.

METHODS

NAVIGATOR was a phase 3, multicentre, randomized, double-blind, placebo-controlled study. Participants (12-80 years old) with severe, uncontrolled asthma were randomized 1:1 to receive tezepelumab 210 mg or placebo subcutaneously every 4 weeks for 52 weeks. Pre-specified and post hoc analyses were performed to evaluate the annualized asthma exacerbation rate (AAER) over 52 weeks in clinically relevant subgroups of patients defined by baseline patient characteristics, medical history, exacerbation triggers, medication eligibility and medication use before and during the study.

RESULTS

Tezepelumab reduced the AAER over 52 weeks compared with placebo across a wide range of patient subgroups assessed. Reductions in exacerbations were similar across subgroups defined by baseline patient characteristics, ranging from 48% (95% confidence interval [CI]: 21, 65) to 60% (95% CI: 44, 71) in subgroups analysed by sex, smoking history and body mass index. Among the asthma-related comorbidity subgroups investigated, patients with aspirin or NSAID sensitivity had the greatest reductions in AAER with tezepelumab compared with placebo (83%; 95% CI: 66, 91). In patients eligible to receive dupilumab, tezepelumab reduced exacerbations compared with placebo by 64% (95% CI: 54, 71). Reductions in the AAER with tezepelumab compared with placebo were also observed irrespective of exacerbation trigger category and the number of asthma controller medications patients were receiving at baseline.

CONCLUSION

These findings further support the benefits of tezepelumab in patients with severe, uncontrolled asthma and can help to inform healthcare providers' treatment decisions.

CLINICAL TRIAL REGISTRATION

NAVIGATOR (NCT03347279).

Comparison of Asthma Phenotypes in Severe Asthma Cohorts (SARP, U-BIOPRED, ProAR and COREA) From 4 Continents

PURPOSE

Asthma is a clinical syndrome with various underlying pathomechanisms and clinical phenotypes. Genetic, ethnic, and geographic factors may influence the differences in clinical presentation, severity, and prognosis. We compared the characteristics of asthma based on the geographical background by analyzing representative cohorts from the United States, Europe, South America, and Asia using the Severe Asthma Research Program (SARP), Unbiased Biomarkers for the Prediction of Respiratory Disease Outcomes (U-BIOPRED), Program for Control of Asthma in Bahia (ProAR), and Cohort for Reality and Evolution of Adult Asthma in Korea (COREA), respectively.

METHODS

The clinical characteristics and medications for the SARP (n = 669), U-BIOPRED (n = 509), ProAR (n = 996), and COREA (n = 3,748) were analyzed. Subgroup analysis was performed for severe asthma.

RESULTS

The mean age was highest and lowest in the COREA and SARP, respectively. The asthma onset age was lowest in the ProAR. The mean body mass index was highest and lowest in the SARP and COREA, respectively. Baseline pulmonary function was lowest and highest in the U-BIOPRED and COREA, respectively. The number of patients with acute exacerbation in the previous year was highest in U-BIOPRED. The mean blood eosinophil count was highest in COREA. The total immunoglobulin E was highest in the ProAR. The frequency of atopy was highest in the SARP. The principal component analysis plot revealed differences among all cohorts.

CONCLUSIONS

The cohorts from 4 different continents exhibited different clinical and physiological characteristics, probably resulting from the interplay between genetic susceptibility and geographical factors.

Predictors of exacerbation in Japanese patients with severe asthma: Analysis of the severe asthma research program (Okayama-SARP) cohort

BACKGROUND

Because exacerbation of severe asthma decreases patients' quality of life, this study aimed to identify predictive factors for asthma exacerbation.

METHODS

Japanese patients with severe asthma requiring treatment according to the Global Initiative for Asthma (GINA) guidelines ≥ Step 4 between January 2018 and August 2021 were prospectively enrolled and followed up for one year at facilities participating in the Okayama Respiratory Disease Study Group (Okayama Severe Asthma Research Program).

RESULTS

A total of 85 patients (29 men and 56 women) were included. The median age was 64 (interquartile range [IQR], 51-72) years. Treatment according to GINA Steps 4 and 5 was required in 29 and 56 patients, respectively, and 44 patients (51.8%) were treated with biologics. The median peripheral-blood eosinophil count, fractional exhaled nitric oxide, IgE level, and percent predicted FEV1 (%FEV1) at enrollment were 204 (IQR, 49-436)/μL, 28 (IQR, 15-43) ppb, 172 (IQR, 56-473) IU/mL, and 80.0 (IQR, 61.1-96.1) %, respectively. Exacerbation during the previous year, asthma control test (ACT) score <20, %FEV1 <60%, and serum IL-10 level >6.7 pg/mL were associated with exacerbation during the observation period.

CONCLUSIONS

Exacerbation during the previous year, low ACT score, and low %FEV1 were predictive factors of future exacerbation, even in a cohort with >50% of patients treated with biologics. Furthermore, high serum IL-10 levels might be a new predictive factor.

Contribution of Obstructive Sleep Apnea to Asthmatic Airway Inflammation and Impact of Its Treatment on the Course of Asthma

Asthma and obstructive sleep apnea (OSA) are very common respiratory disorders in the general population. Beyond their high prevalence, shared risk factors, and genetic linkages, bidirectional relationships between asthma and OSA exist, each disorder affecting the other's presence and severity. The author reviews here some of the salient links between constituents of the alternative overlap syndrome, that is, OSA comorbid with asthma, with an emphasis on the effects of OSA or its treatment on inflammation in asthma. In the directional relationship from OSA toward asthma, beyond direct influences, multiple factors and comorbidities seem to contribute.

The role of radiological imaging in the management of severe and difficult-to-treat asthma

Radiological imaging has proven to be a useful tool in the assessment of asthma, its comorbidities and potential complications. Characteristic chest radiograph and computed tomography scan findings can be seen in asthma and in other conditions that can coexist with or be misdiagnosed as asthma, including chronic rhinosinusitis, inducible laryngeal obstruction, excessive dynamic airway collapse, tracheobronchomalacia, concomitant COPD, bronchiectasis, allergic bronchopulmonary aspergillosis, eosinophilic granulomatosis with polyangiitis, and eosinophilic pneumonia. The identification of the characteristic radiological findings of these conditions is often essential in making the correct diagnosis and provision of appropriate management and treatment. Furthermore, radiological imaging modalities can be used to monitor response to therapy.

Socioeconomic status, diet, and recurrent severe asthma exacerbations in Puerto Rican youth

Background

Why Puerto Rican youths have higher rates of severe asthma exacerbations (SAEs) than their non-Hispanic White peers is unclear.

Objective

We aimed to identify risk factors associated with recurrent SAEs in Puerto Rican youths with asthma.

Methods

We performed cross-sectional and longitudinal analyses of recurrent SAEs in 209 Puerto Rican youths with asthma who participated in 2 cross-sectional studies approximately 5.2 years apart: the Puerto Rico Genetics of Asthma and Lifestyle study (visit 1, participants aged 6-14 years) and the Epigenetic Variation and Childhood Asthma in Puerto Ricans study (visit 2, participants aged 9-20 years). Recurrent SAEs were defined as at least 2 SAEs in the previous year.

Results

Of the youths in our study, there were 80 (38.3%) and 47 (22.4%) with recurrent SAEs at visit 1 and visit 2, respectively, and 31 participants (14.8%) had persistent recurrent SAEs (ie, recurrent SAEs at both visits). In multivariable analyses, low household income was significantly associated with 2.4 to 12.3 times increased odds of recurrent SAEs in all analyses, with stronger longitudinal associations. Low parental education level, nonprivate or employer-based health insurance, overweight or obesity, residential proximity to a major road, and low or moderate level of outdoor activity were each significantly associated with recurrent SAEs in at least 1 analysis. Further, persistence of low parental numeracy level, low household income, and an unhealthy diet were each associated with persistent recurrent SAEs.

Conclusion

In this study of Puerto Rican youths with asthma, persistence of low parental numeracy level, a low household income, and an unhealthy diet were associated with persistent recurrent SAEs. Our findings support policies promoting equity and healthy lifestyles for Puerto Rican children and their families.

Exploring the immunopathology of type 2 inflammatory airway diseases

Significant advancements have been achieved in understanding the roles of different immune cells, as well as cytokines and chemokines, in the pathogenesis of eosinophilic airway conditions. This review examines the pathogenesis of Chronic Rhinosinusitis with Nasal Polyps (CRSwNP), marked by complex immune dysregulation, with major contributions from type 2 inflammation and dysfunctional airway epithelium. The presence of eosinophils and the role of T-cell subsets, particularly an imbalance between Treg and Th17 cells, are crucial to the disease's pathogenesis. The review also investigates the pathogenesis of eosinophilic asthma, a unique asthma subtype. It is characterized by inflammation and high eosinophil levels, with eosinophils playing a pivotal role in triggering type 2 inflammation. The immune response involves Th2 cells, eosinophils, and IgE, among others, all activated by genetic and environmental factors. The intricate interplay among these elements, chemokines, and innate lymphoid cells results in airway inflammation and hyper-responsiveness, contributing to the pathogenesis of eosinophilic asthma. Another scope of this review is the pathogenesis of Eosinophilic Granulomatosis with Polyangiitis (EGPA); a complex inflammatory disease that commonly affects the respiratory tract and small to medium-sized blood vessels. It is characterized by elevated eosinophil levels in blood and tissues. The pathogenesis involves the activation of adaptive immune responses by antigens leading to T and B cell activation and eosinophil stimulation, which causes tissue and vessel damage. On the other hand, Allergic Bronchopulmonary Aspergillosis (ABPA) is a hypersensitive response that occurs when the airways become colonized by aspergillus fungus, with the pathogenesis involving activation of Th2 immune responses, production of IgE antibodies, and eosinophilic action leading to bronchial inflammation and subsequent lung damage. This analysis scrutinizes how an imbalanced immune system contributes to these eosinophilic diseases. The understanding derived from this assessment can steer researchers toward designing new potential therapeutic targets for efficient control of these disorders.

Clinical characteristics in Japanese patients with chronic rhinosinusitis who underwent endoscopic sinus surgery

OBJECTIVE

There is heterogeneity in the pathophysiology of chronic rhinosinusitis (CRS). Obtaining a detailed understanding of patient profiles in specific regions can provide valuable information not only for clinical practice but also future research plans. The aim of this study was to investigate the characteristics of patients who underwent endoscopic sinus surgery (ESS) for CRS.

METHODS

This retrospective, single-center study examined the features of 453 patients with CRS who underwent ESS in the Tokyo area of Japan. The study evaluated various factors in patients with CRS including sex and age, the Japanese Epidemiological Survey of Refractory Eosinophilic Chronic Rhinosinusitis (JESREC) score, the recurrence rate of CRS, comorbidities of asthma and/or allergic diseases, and IgE sensitization to 12 inhaled allergens.

RESULTS

Age-related declines in the sensitization rate to inhaled allergens were observed, and the most notable age-related decrease in specific IgE antibodies was observed for house dust mites (HDM) (p = 8.3 × 10-7). Sensitization to HDM, cat dander, and various types of fungi, including Aspergillus, was frequently observed in the CRS with asthma group, with rates of 54%, 17%, and 17%, respectively. We found that 23% of the patients had recurrence. In the recurrence group, the positive rates of specific IgE antibodies for birch and cat dander were significantly higher than in the no recurrence group. Bronchial asthma was identified as an important factor for recurrence. Among male patients, the recurrence group was younger than the no-recurrence group (p = 0.0032). Severe eosinophilic CRS (ECRS) showed early recurrence after surgery, with over the half of the patients experiencing at least one recurrence within 2 years post-surgery. Among patients with ECRS, the recurrence rate for females was 1.92 times higher than for males.

CONCLUSION

Our study revealed the influences of age and sex on various clinical phenotypes of CRS patients undergoing ESS. There was a high sensitization rate to cat dander in both the recurrence and asthma groups. Further research on diverse disease etiologies is necessary to improve therapeutic strategies for patients with CRS.

Unraveling the Link between Ιnsulin Resistance and Bronchial Asthma

Evidence from large epidemiological studies has shown that obesity may predispose to increased Th2 inflammation and increase the odds of developing asthma. On the other hand, there is growing evidence suggesting that metabolic dysregulation that occurs with obesity, and more specifically hyperglycemia and insulin resistance, may modify immune cell function and in some degree systemic inflammation. Insulin resistance seldom occurs on its own, and in most cases constitutes a clinical component of metabolic syndrome, along with central obesity and dyslipidemia. Despite that, in some cases, hyperinsulinemia associated with insulin resistance has proven to be a stronger risk factor than body mass in developing asthma. This finding has been supported by recent experimental studies showing that insulin resistance may contribute to airway remodeling, promotion of airway smooth muscle (ASM) contractility and proliferation, increase of airway hyper-responsiveness and release of pro-inflammatory mediators from adipose tissue. All these effects indicate the potential impact of hyperinsulinemia on airway structure and function, suggesting the presence of a specific asthma phenotype with insulin resistance. Epidemiologic studies have found that individuals with severe and uncontrolled asthma have a higher prevalence of glycemic dysfunction, whereas longitudinal studies have linked glycemic dysfunction to an increased risk of asthma exacerbations. Since the components of metabolic syndrome interact with one another so much, it is challenging to identify each one's specific role in asthma. This is why, over the last decade, additional studies have been conducted to determine whether treatment of type 2 diabetes mellitus affects comorbid asthma as shown by the incidence of asthma, asthma control and asthma-related exacerbations. The purpose of this review is to present the mechanism of action, and existing preclinical and clinical data, regarding the effect of insulin resistance in asthma.

Upper and lower airway interactions in children

PURPOSE OF REVIEW

The aim of the present review was to highlight the interactions between rhinitis, rhinosinusitis and asthma in children and to discuss the most relevant scientific progresses in the pathophysiology and treatment of these combined conditions.

RECENT FINDINGS

Advances in understanding the mechanisms underlying the relationship between upper and lower airways have provided valuable insights into the role of eosinophils in the pathophysiology of inflammatory events and have further delineated the concept of united airway disease. Studies addressed to evaluate the burden of sinonasal system on asthma outcomes showed a parallel severity of upper and lower airway diseases. Histopathology of sinonasal tissue in patients with chronic rhinosinusitis is different in adults and children. Targeted administration of biological agents represents an effective treatment in patients with severe uncontrolled asthma, but specific trials are awaited in children with chronic sinonasal disease.

SUMMARY

Allergic rhinitis and rhinosinusitis are important comorbidities in patients with asthma. Improved knowledge of pathogenic mechanisms of inflammation and remodelling in the sinonasal system and the lung has led to new therapeutic approaches in patients with united airway disease and opened interesting perspectives for personalized drug therapies.

Smoking, Urban Housing and Work-Aggravated Asthma are Associated with Asthma Severity in a Cross-Sectional Observational Study

Purpose

Severe asthma affects 5 to 10% of asthmatics and accounts for a large part of asthma-related morbidity and costs. The determinants of asthma severity are poorly understood. We tested the hypothesis that asthma severity was associated with 1) atopy and allergy and 2) markers associated with environmental exposure.

Patients and Methods

Data from the FASE-CPHG study, a cross-sectional, observational, multicenter investigation, were analyzed to identify markers associated with asthma severity. Asthma severity was gauged using the ASSESS score, encompassing symptom control, exacerbations, FEV1 and therapeutic load. Bivariate and multivariate analyses were used to identify patient characteristics associated with the ASSESS score.

Results

The analysis involved 948 patients, with 592 women, of which 447 patients (47%) had severe asthma. Among these, 491 patients (52%) had at least one positive aeroallergen skin prick test and 525 (55%) had at least one allergic disease among atopic dermatitis, chronic rhinitis and food allergy. The mean±SD ASSESS score was 11.2±3.4. Characteristics associated with a higher ASSESS score were female sex, secondary or lower education, unemployed occupational status, smoking, work-aggravated asthma and urban housing. There was no association between the ASSESS score and allergic diseases, aeroallergen-specific skin prick tests and IgEs, or blood eosinophil counts.

Conclusion

While atopy and allergy were frequent among asthmatics, neither was associated with asthma severity. Modifiable environmental factors such as smoking, urban housing and work-aggravated asthma were independently associated with asthma severity.

Obesity and Insulin Resistance in Asthma Pathogenesis and Clinical Outcomes

Common inflammatory ground links obesity, insulin resistance, and asthma. As recognition of their interplay, one worsening the natural course of the other, is recognised, questions remain about how to adequately address them altogether to improve clinical outcomes. The present manuscript sheds light on the problem, describing possible pathophysiological links, clinical views, and therapeutic challenges, raising questions about what remains to be done, and calling for multidisciplinary treatment of these patients to detect diseases early and adequately address them before they become full-blown and deteriorate their health and quality of life.

Asthma and obstructive sleep apnea: Unveiling correlations and treatable traits for comprehensive care

Asthma and obstructive sleep apnea (OSA) are common respiratory disorders. They share characteristics such as airway obstruction, poor sleep quality, and low quality of life. They are often present as comorbidities, along with obesity, gastroesophageal reflux disease (GERD), and allergic rhinitis (AR), which impacts the disease's control. In recent years, there has been discussion about the association between these conditions and their pathophysiological and clinical consequences, resulting in worse health outcomes, increased healthcare resource consumption, prolonged hospital stays, and increased morbidity and mortality. Some studies demonstrate that treatment with continuous positive airway pressure (CPAP) can have a beneficial effect on both pathologies. This review summarizes the existing evidence of the association between asthma and OSA at their pathophysiological, epidemiological, clinical, and therapeutic levels. It intends to raise awareness among healthcare professionals about these conditions and the need for further research.

Analysis of comorbidities and multimorbidity in adult patients in the International Severe Asthma Registry

BACKGROUND

Investigation for the presence of asthma comorbidities is recommended by the Global Initiative for Asthma because their presence can complicate asthma management.

OBJECTIVE

To understand the prevalence and pattern of comorbidities and multimorbidity in adults with severe asthma and their association with asthma-related outcomes.

METHODS

This was a cross-sectional study using data from the International Severe Asthma Registry from 22 countries. A total of 30 comorbidities were identified and categorized a priori as any of the following: (1) potentially type 2-related comorbidities, (2) potentially oral corticosteroid (OCS)-related comorbidities, or (3) comorbidities mimicking or aggravating asthma. The association between comorbidities and asthma-related outcomes was investigated using multivariable models adjusted for country, age at enrollment, and sex (ie male or female).

RESULTS

Of the 11,821 patients, 69%, 67%, and 55% had at least 1 potentially type 2-related, potentially OCS-related, or mimicking or aggravating comorbidities, respectively; 57% had 3 or more comorbidities, and 33% had comorbidities in all 3 categories. Patients with allergic rhinitis, nasal polyposis, and chronic rhinosinusitis experienced 1.12 (P = .003), 1.16 (P < .001), and 1.29 times (P < .001) more exacerbations per year, respectively, than those without. Patients with nasal polyposis and chronic rhinosinusitis were 40% and 46% more likely (P < .001), respectively, to have received long-term (LT) OCS. All assessed potential OCS-related comorbidities (except obesity) were associated with a greater likelihood of LTOCS use (odds ratios [ORs]: 1.23-2.77) and, except for dyslipidemia, with a greater likelihood of uncontrolled asthma (ORs: 1.29-1.68). All mimicking or aggravating comorbidities assessed were associated with more exacerbations (1.24-1.68 times more), all (except bronchiectasis) with increased likelihood of uncontrolled asthma (ORs: 1.57-1.81), and all (except chronic obstructive pulmonary disease) with increased likelihood of LTOCS use (ORs: 1.37-1.57). A greater number of comorbidities was associated with worse outcomes.

CONCLUSION

In a global study, comorbidity or multimorbidity is reported in most adults with severe asthma and is associated with poorer asthma-related outcomes.

CLINICAL TRIAL REGISTRATION

The International Severe Asthma Registry database has ethical approval from the Anonymous Data Ethics Protocols and Transparency (ADEPT) committee (ADEPT0218) and is registered with the European Union Electronic Register of Post-Authorization Studies (European Network Centres for Pharmacoepidemiology and Pharmacovigilance [ENCEPP]/DSPP/23720). The study was designed, implemented, and reported in compliance with the European Network Centres for Pharmacoepidemiology and Pharmacovigilance (ENCEPP) Code of Conduct (EMA 2014; EUPAS44024) and with all applicable local and international laws and regulations, and registered with ENCEPP (https://www.encepp.eu/encepp/viewResource.htm?id=48848). Governance was provided by ADEPT (registration number: ADEPT1121).

Prediction of Asthma Exacerbations in Children

Asthma exacerbations are common in asthmatic children, even among those with good disease control. Asthma attacks result in the children and their parents missing school and work days; limit the patient's social and physical activities; and lead to emergency department visits, hospital admissions, or even fatal events. Thus, the prompt identification of asthmatic children at risk for exacerbation is crucial, as it may allow for proactive measures that could prevent these episodes. Children prone to asthma exacerbation are a heterogeneous group; various demographic factors such as younger age, ethnic group, low family income, clinical parameters (history of an exacerbation in the past 12 months, poor asthma control, poor adherence to treatment, comorbidities), Th2 inflammation, and environmental exposures (pollutants, stress, viral and bacterial pathogens) determine the risk of a future exacerbation and should be carefully considered. This paper aims to review the existing evidence regarding the predictors of asthma exacerbations in children and offer practical monitoring guidance for promptly recognizing patients at risk.

Deep learning prediction of hospital readmissions for asthma and COPD

QUESTION

Severe asthma and COPD exacerbations requiring hospitalization are linked to increased disease morbidity and healthcare costs. We sought to identify Electronic Health Record (EHR) features of severe asthma and COPD exacerbations and evaluate the performance of four machine learning (ML) and one deep learning (DL) model in predicting readmissions using EHR data.

STUDY DESIGN AND METHODS

Observational study between September 30, 2012, and December 31, 2017, of patients hospitalized with asthma and COPD exacerbations.

RESULTS

This study included 5,794 patients, 1,893 with asthma and 3,901 with COPD. Patients with asthma were predominantly female (n = 1288 [68%]), 35% were Black (n = 669), and 25% (n = 479) were Hispanic. Black (44 vs. 33%, p = 0.01) and Hispanic patients (30 vs. 24%, p = 0.02) were more likely to be readmitted for asthma. Similarly, patients with COPD readmissions included a large percentage of Blacks (18 vs. 10%, p < 0.01) and Hispanics (8 vs. 5%, p < 0.01). To identify patients at high risk of readmission index hospitalization data of a subset of 2,682 patients, 777 with asthma and 1,905 with COPD, was analyzed with four ML models, and one DL model. We found that multilayer perceptron, the DL method, had the best sensitivity and specificity compared to the four ML methods implemented in the same dataset.

INTERPRETATION

Multilayer perceptron, a deep learning method, had the best performance in predicting asthma and COPD readmissions, demonstrating that EHR and deep learning integration can improve high-risk patient detection.

Mitochondrial DNA Copy Number Variation in Asthma Risk, Severity, and Exacerbations

Rationale

Although airway oxidative stress and inflammation are central to asthma pathogenesis, there is limited knowledge of the relationship of asthma risk, severity, or exacerbations to mitochondrial dysfunction, which is pivotal to oxidant generation and inflammation.

Objectives

We investigated whether mitochondrial DNA copy number (mtDNA-CN) as a measure of mitochondrial function is associated with asthma diagnosis, severity, oxidative stress, and exacerbations.

Methods

We measured mtDNA-CN in blood in two cohorts. In the UK Biobank (UKB), we compared mtDNA-CN in mild and moderate-severe asthmatics to non-asthmatics. In the Severe Asthma Research Program (SARP), we evaluated mtDNA-CN in relation to asthma severity, biomarkers of oxidative stress and inflammation, and exacerbations.

Measures and Main Results

In UK Biobank, asthmatics (n = 29,768) have lower mtDNA-CN compared to non-asthmatics (n = 239,158) (beta, -0.026 [95% CI, -0.038 to -0.014], P = 2.46×10-5). While lower mtDNA-CN is associated with asthma, mtDNA-CN did not differ by asthma severity in either UKB or SARP. Biomarkers of inflammation show that asthmatics have higher white blood cells (WBC), neutrophils, eosinophils, fraction exhaled nitric oxide (FENO), and lower superoxide dismutase (SOD) than non-asthmatics, confirming greater oxidative stress in asthma. In one year follow-up in SARP, higher mtDNA-CN is associated with reduced risk of three or more exacerbations in the subsequent year (OR 0.352 [95% CI, 0.164 to 0.753], P = 0.007).

Conclusions

Asthma is characterized by mitochondrial dysfunction. Higher mtDNA-CN identifies an exacerbation-resistant asthma phenotype, suggesting mitochondrial function is important in exacerbation risk.

Mepolizumab in Patients With Severe Asthma and Comorbidities: 1-Year REALITI-A Analysis

BACKGROUND

Severe asthma is complex; comorbidities may influence disease outcomes.

OBJECTIVE

To assess mepolizumab effectiveness in patients with severe asthma and comorbidities.

METHODS

REALITI-A was a 2-year international, prospective study enrolling adults with asthma newly prescribed mepolizumab (100 mg subcutaneously) at physician's discretion. This post hoc analysis assessed 1-year outcomes stratified by comorbidities at enrollment: chronic rhinosinusitis with nasal polyps (CRSwNP), gastroesophageal reflux disease (GERD), depression/anxiety, and chronic obstructive pulmonary disease (COPD). Outcomes included the rate of clinically significant asthma exacerbations (CSEs; requiring systemic corticosteroids and/or hospital/emergency room admission) between the 12 months pre- and post-mepolizumab treatment and changes from baseline in daily maintenance oral corticosteroid dose (mo 12), Asthma Control Questionnaire-5 score (mo 12) and forced expiratory volume in 1 second (FEV1; mo 9-12).

RESULTS

At enrollment (n = 822), 321 of 822 (39%), 309 of 801 (39%), 203 of 785 (26%), and 81 of 808 (10%) patients had comorbid CRSwNP, GERD, depression/anxiety, and COPD, respectively. Post- versus pre-treatment across all comorbidity subgroups: the rate of CSEs decreased by 63% or more; among 298 (39%) patients on maintenance oral corticosteroids at baseline, median dose decreased by 50% or more; Asthma Control Questionnaire-5 score decreased by 0.63 or more points; FEV1 increased by 74 mL or more. Patients with versus without CRSwNP had the greatest improvements (eg, rate of CSEs decreased by 75%). Patients without GERD, depression/anxiety, or COPD had greater improvements than those with the respective comorbidities, except for FEV1 in patients with COPD.

CONCLUSIONS

Mepolizumab improved disease outcomes in patients with severe asthma irrespective of comorbidities, with additional benefit for patients with CRSwNP.

Dupilumab leads to better-controlled asthma and quality of life in children: the VOYAGE study

BACKGROUND

Dupilumab has shown long-term treatment benefits in children with uncontrolled asthma. We assessed in more detail the impact of dupilumab on asthma control and health-related quality of life (HRQoL) in children and their caregivers.

METHODS

Children aged 6-11 years with uncontrolled moderate-to-severe type 2 asthma (baseline blood eosinophils ≥150 cells·µL-1 or fractional exhaled nitric oxide ≥20 ppb; n=350) were treated with dupilumab or placebo for 52 weeks in the VOYAGE study. Primary outcomes of these analyses were asthma control (change from baseline in Asthma Control Questionnaire 7 Interviewer-Administered (ACQ-7-IA) and achieving a clinically meaningful response of ≥0.5 points); proportion of patients achieving well-controlled asthma or better (ACQ-7-IA ≤0.75 points); effect on patients' (Standardised Paediatric Asthma Quality of Life Questionnaire Interviewer-Administered (PAQLQ(S)-IA)) and caregivers' (Paediatric Asthma Caregiver's Quality of Life Questionnaire (PACQLQ)) HRQoL; and allergic rhinitis-related QoL.

RESULTS

Dupilumab versus placebo significantly improved children's ACQ-7-IA scores by week 4 with sustained improvements through week 52 (least squares mean difference at week 52: -0.44, 95% CI -0.59- -0.30; p<0.0001); a higher proportion achieved a clinically meaningful response (week 52: 86% versus 75%; p=0.0051). At weeks 24 and 52, more children who received dupilumab achieved well-controlled asthma (ACQ-7-IA ≤0.75 points: 61% versus 43%; p=0.0001 and 70% versus 46%; p<0.0001, respectively). Significant improvements in PAQLQ(S)-IA and PACQLQ scores were observed by week 52.

CONCLUSIONS

In children aged 6-11 years with moderate-to-severe type 2 asthma, dupilumab treatment was associated with rapid, sustained improvements in asthma control. HRQoL was significantly improved for children and their caregivers.