Identification of asthma phenotypes using cluster analysis in the Severe Asthma Research Program

What is the role of asthma in obstructive sleep apnea? A narrative review

INTRODUCTION

Asthma and obstructive sleep apnea (OSA) are two of the most prevalent respiratory diseases in the world. Their high prevalence increases the probability of the two diseases coexisting by chance in a single individual, but in recent years, various studies have also shown a real one-to-one association between them.

DATA SOURCES

PubMed. Keywords: asthma (title) and OSA (title) and apnea (title) and positive airway pressure and CPAP (title).

STUDIES SELECTION

All manuscript related to the relationship between asthma an OSA as well as its treatments in terms of pathophysiological, diagnostic, etiological, epidemiological and treatment points.

RESULTS

50% of asthmatic patients suffer from OSA and the adjusted risk of developing OSA in asthmatics is 2.5 times higher than in non-asthmatic individuals, especially in poorly controlled, more severe or longer-standing asthmatics. Several mechanisms have been postulated to explain this increase in OSA in asthmatics: obesity, gastro-esophageal reflux, rhinitis, nasal polyps, increased pharyngeal collapsibility due to mechanical, inflammatory or dynamic causes and, finally, the upper airway deposition of inhaled corticosteroids (IC) generating myopathy in the pharyngeal muscles (as occurs in the vocal cord muscles, resulting in dysphonia).

CONCLUSIONS

Although both asthma and OSA are common diseases that can coexist in the same individual, a one-to-one association between the two diseases has been observed. The presence of asthma could generate or exacerbate a preexisting OSA. Caution is recommended in IC inhalation techniques in patients with OSA. The use of ultrafine particles with less pharyngeal deposition is recommended.

Cough-Variant Asthma: A Review of Clinical Characteristics, Diagnosis, and Pathophysiology

Chronic cough is among the most common symptoms prompting medical care. Cough-variant asthma (CVA) is an asthma subset where cough is the primary symptom, without wheezing, chest tightness, or dyspnea. It is an important cause of chronic cough, estimated to account for 25% to 42% of cases, but likely underdiagnosed due to delayed recognition and pitfalls of diagnostic testing. Early recognition and treatment can reduce morbidity and delay its progression to more typical asthma. This review details the clinical characteristics, diagnosis, pathophysiology, and treatment of CVA and contrasts it with classic asthma and other causes of chronic cough.

Clinical characteristics and biological treatment responses of patients with late-onset asthma phenotype

Background: The data on subphenotypes and treatment responses to biologicals in late-onset asthma (LOA) is limited. This study aims to compare the clinical characteristics and treatment responses in severe asthma patients receiving biological treatments, categorized into early-onset asthma (EOA) and LOA groups. Methods: Patients treated with omalizumab or mepolizumab for at least six months at a tertiary care adult allergy clinic between December 2015 and December 2023 were included. Patients with persistent respiratory symptoms starting at age ≥40 years were categorized as LOA, while those with onset <40 years were categorized as EOA. Changes in Asthma Control Questionnaire (ACQ-6) scores, forced expiratory volume in one second (FEV1) percentages, and blood eosinophil counts were assessed at baseline and 6 months. The percentage change in FEV1 (liters) at 6 months relative to baseline was measured. Clinical remission rates were evaluated in those completing one year of treatment. Results: Among 87 patients, 38 (43.7%) had LOA and 49 (56.3%) had EOA. Of these, 22 (25.3%) received omalizumab and 65 (74.7%) received mepolizumab, with a mean treatment duration of 24.7 (±19.7) months. LOA patients had higher obesity rates and tobacco consumption compared to EOA patients (p = 0.041 and p = 0.024, respectively). There were no significant differences between LOA and EOA groups in ACQ scores, FEV1 percentage, the percentage change in FEV1 in liters and eosinophil counts (p = 0.531, p = 0.219, p = 0.632, p = 0.700, respectively). Within LOA patients, ACQ scores did not significantly differ between those treated with omalizumab and mepolizumab (p = 0.801). At 6 months, eosinophil counts significantly decreased with mepolizumab but not with omalizumab (p = 0.002). Conclusion: Biological treatment responses were similar between LOA and EOA groups. Omalizumab and mepolizumab showed comparable efficacy, with the exception of eosinophil count changes in LOA patients.

Leptin augments IL-13-induced airway eotaxins and submucosal eosinophilia in obesity-associated asthma

BACKGROUND

Airway tissue eosinophilia can be an observed feature of obesity-associated type 2 (T2) asthma, but the processes mediating this inflammation are unknown.

OBJECTIVE

To investigate a process whereby leptin, an adipokine elevated in obesity, potentiates pulmonary eosinophilia and eotaxin production by airway fibroblasts in T2 asthma.

METHODS

We assessed associations between body mass index and airway eosinophilia as well as leptin and eotaxin production in 82 participants with asthma, 37 of whom exhibited obesity. Cultured human airway fibroblasts and mouse models of chronic allergic airway disease were used to evaluate leptin's effect on eotaxin production and lung eosinophilia. The role of IL-13 receptor alpha 2 (IL-13Rα2) in mediating these processes was examined using specific neutralizing antibodies in vitro.

RESULTS

In participants with T2 asthma and obesity, we observed that airway tissue eosinophilia did not associate with traditional T2 inflammation metrics such as peripheral and/or bronchoalveolar lavage fluid eosinophil counts or with fractional exhaled nitric oxide. Alternatively, we observed elevated bronchoalveolar lavage fluid leptin and eotaxin-1 levels. In airway fibroblasts from participants with asthma, leptin augmented IL-13-induced eotaxin-1 and eotaxin-3 production and IL13RA2 expression. In mice, elevated leptin promoted airway IL-13Rα2 and eotaxin production by lung fibroblasts and lung tissue eosinophilia following chronic house dust mite allergen exposure. Inhibition of IL-13Rα2 reduced combined leptin and IL-13-stimulated eotaxin secretion by human airway fibroblasts.

CONCLUSIONS

We identified a potential association explaining airway tissue eosinophil retention in obesity-associated T2 asthma through leptin-mediated enhancement of IL-13-induced eosinophil chemokine production by airway fibroblasts, a process requiring IL-13Rα2.

Glucagon-Like Peptide 1 Receptor (Glp1r) Deficiency Does Not Appreciably Alter Airway Inflammation or Gut-Lung Microbiome Axis in a Mouse Model of Obese Allergic Airways Disease and Bariatric Surgery

Purpose

High body mass index (≥30 kg/m2) is associated with asthma severity, and nearly 40% of asthma patients exhibit obesity. Furthermore, over 40% of patients with obesity and asthma that receive bariatric surgery no longer require asthma medication. Increased levels of glucagon-like peptide 1 (GLP-1) occur after bariatric surgery, and recent studies suggest that GLP-1 receptor (GLP-1R) signaling may regulate the gut microbiome and have anti-inflammatory properties in the lung. Thus, we hypothesized that increased GLP-1R signaling following metabolic surgery in obese and allergen-challenged mice leads to gut/lung microbiome alterations, which together contribute to improved features of allergic airways disease.

Methods

Male and female Glp1r-deficient (Glp1r-/- ) and replete (Glp1r+/+) mice were administered high fat diet (HFD) to induce obesity with simultaneous intranasal challenge with house dust mite (HDM) allergen to model allergic airway disease with appropriate controls. Mice on HFD received either no surgery, sham surgery, or vertical sleeve gastrectomy (VSG) on week 10 and were sacrificed on week 13. Data were collected with regard to fecal and lung tissue microbiome, lung histology, metabolic markers, and respiratory inflammation.

Results

HFD led to metabolic imbalance characterized by lower GLP-1 and higher leptin levels, increased glucose intolerance, and alterations in gut microbiome composition. Prevalence of bacteria associated with short chain fatty acid (SCFA) production, namely Bifidobacterium, Lachnospiraceae UCG-001, and Parasutterella, was reduced in mice fed HFD and positively associated with serum GLP-1 levels. Intranasal HDM exposure induced airway inflammation. While Glp1r-/- genotype affected fecal microbiome beta diversity metrics, its effect was limited.

Conclusion

Herein, GLP-1R deficiency had surprisingly little effect on host gut and lung microbiomes and health, despite recent studies suggesting that GLP-1 receptor agonists are protective against lung inflammation.

The Role of Fractional Exhaled Nitric Oxide and Oscillometry in Pediatric Asthma

Diagnosing pediatric asthma is challenging and requires the evaluation of symptoms, inflammation, and lung function. Spirometry, which is commonly used to evaluate lung function in asthma, is difficult to obtain from young pediatric patients and frequently not possible to obtain from patients under 5 years of age. This is also true for the fraction of exhaled nitric oxide (FENO) measurement, which can indicate type 2 airway inflammation in asthma, and controversy has existed regarding the appropriate use of FENO measurement in asthma diagnosis and monitoring. Impulse oscillometry can be used to evaluate lung function and may be easier to perform than spirometry for pediatric patients. This narrative review evaluates the recent guidelines for diagnosis and monitoring of pediatric asthma. It also provides an overview of the use of FENO measurement and impulse oscillometry in pediatric asthma. A panel discussion of the role of FENO measurement and impulse oscillometry in pediatric asthma concludes this article.

Economic Evaluation of Mepolizumab as Add-on Therapy to Standard Care in Severe Eosinophilic Asthma: A Cost-Effectiveness Analysis in Colombia

Background

Mepolizumab, an IL-5 receptor antagonist, is a targeted therapy approved for treating severe eosinophilic persistent asthma. While it offers significant clinical benefits in reducing exacerbations and improving quality of life, its high cost raises concerns about its affordability and overall value in resource-constrained settings. This study evaluates the cost-effectiveness of adding mepolizumab to standard care (SoC) compared to SoC alone in adolescents and adults with severe, uncontrolled eosinophilic asthma in Colombia.

Methods

We used a Markov model with a societal perspective and a lifetime horizon to estimate costs and quality-adjusted life years (QALYs). Parameters were derived from local data and existing literature. Both deterministic and probabilistic sensitivity analyses were performed to test the model's robustness. Cost-effectiveness was assessed using a willingness-to-pay threshold of US$5,130.

Results

Mepolizumab demonstrated an additional 0.31 QALYs per patient compared to standard of care (SoC), with an incremental cost-effectiveness ratio (ICER) of US$25,210 per QALY gained. Sensitivity analyses showed that the price of mepolizumab was the key driver of cost-effectiveness. Over a 5-year horizon, adding mepolizumab to SoC would have a significant budgetary impact. These findings highlight the need to balance clinical benefit with affordability in resource-limited settings.

Conclusion

Although mepolizumab improves patients' quality of life, it is not considered cost-effective in Colombia under the conditions of this study. The results provide valuable information for policymakers to consider when refining local clinical practice guidelines.

Asthma Phenotypes and Biomarkers

Asthma experienced by both adults and children is a phenotypically heterogeneous condition. Severe asthma, characterized by ongoing symptoms and airway inflammation despite high doses of inhaled and/or systemic corticosteroids, is the focus of research efforts to understand this underlying heterogeneity. Clinical phenotypes in both adult and pediatric asthma have been determined using supervised definition-driven classification and unsupervised data-driven clustering methods. Efforts to understand the underlying inflammatory patterns of severe asthma have led to the seminal discovery of type 2-high versus type 2-low phenotypes and to the development of biologics targeted at type 2-high inflammation to reduce the rates of severe asthma exacerbations. Type 2-high asthma is characterized by upregulation of T helper 2 immune pathways including interleukin (IL)-4, IL-5, and IL-13 along with eosinophilic airway inflammation, sometimes allergic sensitization, and responsiveness to treatment with corticosteroids. Type 2-low asthma is poorly responsive to corticosteroids and is not as well characterized as type 2-high asthma. Type 2-low asthma is limited by being defined as the absence of type 2-high inflammatory markers. Choosing a biologic for the treatment of severe asthma involves the evaluation of a panel of biomarkers such as blood eosinophils, total and specific immunoglobulin E/allergic sensitization, and fractional exhaled nitric oxide. In this review, we focus on the underlying pathobiology of adult and pediatric asthma, discuss the different phenotype-based treatment options for adult and pediatric type 2-high with or without allergic asthma and type 2-low asthma, and describe a clinical phenotyping approach to patients to guide out-patient therapy. Finally, we end with a discussion of whether pediatric asthma exacerbations necessitating admission to an ICU constitute their own high-risk phenotype and/or whether it is a part of other previously defined high-risk subgroups such as difficult-to-control asthma, exacerbation-prone asthma, and severe treatment-resistant asthma.

Computational Phenotyping of Obstructive Airway Diseases: A Systematic Review

Introduction

Computational sciences have significantly contributed to characterizing airway disease phenotypes, complementing medical expertise. However, comparing studies that derive phenotypes is challenging due to varying decisions made during phenotyping. We conducted a systematic review to describe studies that utilized unsupervised computational approaches for phenotyping obstructive airway diseases in children and adults.

Methods

We searched for relevant papers published between 2010 and 2020 in PubMed, EMBASE, Scopus, Web of Science, and Google Scholar. Additional sources included conference proceedings, reference lists, and expert recommendations. Two reviewers independently screened studies for eligibility, extracted data, and assessed study quality. Disagreements were resolved by a third reviewer. An in-house quality appraisal tool was used. Evidence was synthesized, focusing on populations, variables, and computational approaches used for deriving phenotypes.

Results

Of 120 studies included in the review, 60 focused on asthma, 19 on severe asthma, 28 on COPD, 4 on asthma-COPD overlap (ACO), and 9 on rhinitis. Among asthma studies, 31 focused on adults and 9 on children, with phenotypes related to atopy, age at onset, and disease severity. Severe asthma phenotypes were characterized by symptomatology, atopy, and age at onset. COPD phenotypes involved lung function, emphysematous changes, smoking, comorbidities, and daily life impairment. ACO and rhinitis phenotypes were mostly defined by symptoms, lung function, and sensitization, respectively. Most studies used hierarchical clustering, with some employing latent class modeling, mixture models, and factor analysis. The comprehensiveness of variable reporting was the best quality indicator, while reproducibility measures were often lacking.

Conclusion

Variations in phenotyping methods, study settings, participant profiles, and variables contribute to significant differences in characterizing asthma, severe asthma, COPD, ACO, and rhinitis phenotypes across studies. Lack of reproducibility measures limits the evaluation of computational phenotyping in airway diseases, underscoring the need for consistent approaches to defining outcomes and selecting variables to ensure reliable phenotyping.

A comparison of the impact of anti-IL5/5r therapies in allergic versus non-allergic patients with severe eosinophilic asthma in a real-life setting

OBJECTIVE

This study aimed to compare the clinical characteristics and treatment outcomes of allergic patients (AP) and non-allergic patients (NAP) with severe eosinophilic asthma (SEA) treated with anti-IL5/IL5R biologic agents (mepolizumab, benralizumab, or reslizumab) over one year. Sub-analyses assessed treatment response variations between AP and NAP based on the biological used and compared outcomes among AP with and without fungal allergy.

METHODS

Observational retrospective analysis. Clinical characteristics, laboratory findings, pulmonary function tests, Asthma Control Test (ACT) scores, oral corticosteroid (OCS) usage, and exacerbation frequency were assessed at the initiation of biological treatment and after one year.

RESULTS

Sixty-five patients with SEA were included, 41 AP and 24 NAP. 55.4% were treated with mepolizumab, 33.8% with benralizumab, and 10.8% with reslizumab. Before anti-IL5/5R treatment, AP had worse baseline outcomes but there were no differences in pulmonary function. Mean annual exacerbation rate and percentage of patients requiring OCS and dose of prednisone were higher in AP than NAP. AP had significantly higher total IgE values. After one year of treatment, more AP discontinued OCS than NAP (p = 0.025). Both experienced a significant reduction in exacerbation frequency (p = 0.001) and improved respiratory function. 70.7% of AP and 60% of NAP improved ACT ≥3 points. There was no significant difference between AP and NAP using mepolizumab (p = 0.145) or benralizumab (p = 0.174) in reducing OCS.

CONCLUSIONS

Anti-IL5/IL5R reduced the need for OCS and improved asthma control, regardless of allergic status. Fungal allergy led to lower ACT scores and higher exacerbations than other allergens; both groups improved with anti-IL5/ILR.

Copy Number Variation in Asthma: An Integrative Review

Asthma is a complex disease with varied clinical manifestations resulting from the interaction between environmental and genetic factors. While chronic airway inflammation and hyperresponsiveness are central features, the etiology of asthma is multifaceted, leading to a diversity of phenotypes and endotypes. Although most research into the genetics of asthma focused on the analysis of single nucleotide polymorphisms (SNPs), studies highlight the importance of structural variations, such as copy number variations (CNVs), in the inheritance of complex characteristics, but their role has not yet been fully elucidated in asthma. In this context, an integrative review was conducted to identify the genes and pathways involved, the location, size, and classes of CNVs, as well as their contribution to asthma risk, severity, control, and response to treatment. As a result of the review, 16 articles were analyzed, from different types of observational studies, such as case-control, cohort studies and genotyped-proband or trios design, that have been carried out in populations from different countries, ethnicities, and ages. Chromosomes 12 and 17 were the most studied in three publications each. CNVs located on 12 chromosomes were associated with asthma, the majority being found on chromosome 6p and 17q, of the deletion type, encompassing 30 different coding-protein genes and one pseudogene region. Six genes with CNVs were identified as significant expression quantitative locus (eQTLs) with mean expression in asthma-related tissues, such as the lung and whole blood. The phenotypic variability of asthma may hinder the clinical application of these findings, but the research shows the importance of investigating these genetic variations as possible biomarkers in asthma patients.

Identifying super-responders: A review of the road to asthma remission

Asthma is a chronic respiratory disease marked by heterogeneity and variable clinical outcomes. Recent therapeutic advances have highlighted patients achieving optimal outcomes, termed "remission" or "super-response." This review evaluates the various definitions of these terms and explores how disease burden impedes the attainment of remission. We assessed multiple studies, including a recent systematic review and meta-analysis, on biologic treatments for asthma remission. Our review highlights that type 2 inflammation may be the strongest predictor of biologic response. Key comorbidities (eg, obesity and mood disorders) and behavioral factors (eg, poor adherence, improper inhalation technique, and smoking) were identified as dominant traits limiting remission. In addition, asthma burden and longer disease duration significantly restrict the potential for remission in patients with severe asthma under the current treatment paradigm. We review the potential for a "predict-and-prevent" approach, which focuses on early identification of high-risk patients with type 2 inflammation and aggressive treatment to improve long-term asthma outcomes. In conclusion, this scoping review highlights the following unmet needs in asthma remission: (1) a harmonized global definition, with better defined lung function parameters; (2) integration of nonbiologic therapies into remission strategies; and (3) a clinical trial of early biologic intervention in patients with remission-prone, very type 2-high, moderately severe asthma with clinical remission as a predefined primary end point.

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.

SnS2 QDs@MXene Ohmic Junction-Based Surface Plasmon Coupling ECL Sensor to Detect Saliva Exosome for the Diagnosis of Childhood Asthma

This study represents a novel surface plasmon coupling electrochemiluminescence (SPC-ECL) method for detecting salivary exosomes and the diagnosis of childhood asthma. First, SnS2 QDs@MXene Ohmic junctions was developed as efficient ECL emitters. The Ohmic junction provided a low resistance to reduce the contact resistance and improve charge injection efficiency, which enhanced the ECL signal by 2.76 times. Furthermore, the self-assembled surface plasmonic Bi@SiO2 array was prepared. When the ECL of SnS2 QDs@MXene resonated with the electronic oscillations in the Bi@SiO2 NPs array, the luminescence intensity was enhanced and regulated into the directionally polarized signal by the SPC-ECL effect. Remarkably, the detection of CD9-exosomes in saliva was achieved successfully based on the above sensing system, which can be used to analysis the acute exacerbation and chronic persistence of childhood asthma.

Clinical Potential of Misshapen/NIKs-Related Kinase (MINK) 1-A Many-Sided Element of Cell Physiology and Pathology

Misshapen/NIKs-related kinase (MINK) 1 belongs to the mammalian germinal center kinase (GCK) family. It contains the N-terminal, conserved kinase domain, a coiled-coil region, a proline-rich region, and a GCK, C-terminal domain with the Citron-NIK-Homology (CNH) domain. The kinase is an essential component of cellular signaling pathways, which include Wnt signaling, JNK signaling, pathways engaging Ras proteins, the Hippo pathway, and STRIPAK complexes. It thus contributes to regulating the cell cycle, apoptosis, cytoskeleton organization, cell migration, embryogenesis, or tissue homeostasis. MINK1 plays an important role in immunological responses, inhibiting Th17 and Th1 cell differentiation and regulating NLRP3 inflammasome function. It may be considered a link between ROS and the immunological system, and a potential antiviral target for human enteroviruses. The kinase has been implicated in the pathogenesis of sepsis, rheumatoid arthritis, asthma, SLE, and more. It is also involved in tumorigenesis and drug resistance in cancer. Silencing MINK1 reduces cancer cell migration, suggesting potential for new therapeutic approaches. Targeting MINK1 could be a promising treatment strategy for patients insensitive to current chemotherapies, and could improve their prognosis. Moreover, MINK1 plays an important role in the nervous system and the cardiovascular system development and function. The modulation of MINK1 activity could influence the course of neurodegenerative diseases, including Alzheimer's disease. Further exploration of the activity of the kinase could also help in gaining more insight into factors involved in thrombosis or congenital heart disease. This review aims to summarize the current knowledge on MINK1, highlight its therapeutic and prognostic potential, and encourage more studies in this area.

Identification of severe acute pediatric asthma phenotypes using unsupervised machine learning

RATIONALE

More targeted management of severe acute pediatric asthma could improve clinical outcomes.

OBJECTIVES

To identify distinct clinical phenotypes of severe acute pediatric asthma using variables obtained in the first 12 h of hospitalization.

METHODS

We conducted a retrospective cohort study in a quaternary care children's hospital from 2014 to 2022. Encounters for children ages 2-18 years admitted to the hospital for asthma were included. We used consensus k means clustering with patient demographics, vital signs, diagnostics, and laboratory data obtained in the first 12 h of hospitalization.

MEASUREMENTS AND MAIN RESULTS

The study population included 683 encounters divided into derivation (80%) and validation (20%) sets, and two distinct clusters were identified. Compared to Cluster 1 in the derivation set, Cluster 2 encounters (177 [32%]) were older (11 years [8; 14] vs. 5 years [3; 8]; p < .01) and more commonly males (63% vs. 53%; p = .03) of Black race (51% vs. 40%; p = .03) with non-Hispanic ethnicity (96% vs. 84%; p < .01). Cluster 2 encounters had smaller improvements in vital signs at 12-h including percent change in heart rate (-1.7 [-11.7; 12.7] vs. -7.8 [-18.5; 1.7]; p < .01), and respiratory rate (0.0 [-20.0; 22.2] vs. -11.4 [-27.3; 9.0]; p < .01). Encounters in Cluster 2 had lower percentages of neutrophils (70.0 [55.0; 83.0] vs. 85.0 [77.0; 90.0]; p < .01) and higher percentages of lymphocytes (17.0 [8.0; 32.0] vs. 9.0 [5.3; 14.0]; p < .01). Cluster 2 encounters had higher rates of invasive mechanical ventilation (23% vs. 5%; p < .01), longer hospital length of stay (4.5 [2.6; 8.8] vs. 2.9 [2.0; 4.3]; p < .01), and a higher mortality rate (7.3% vs. 0.0%; p < .01). The predicted cluster assignments in the validation set shared the same ratio (~2:1), and many of the same characteristics.

CONCLUSIONS

We identified two clinical phenotypes of severe acute pediatric asthma which exhibited distinct clinical features and outcomes.

Clinical characteristics of complete responders versus non-complete responders to omalizumab, benralizumab and mepolizumab in patients with severe asthma: a long-term retrospective analysis

BACKGROUND

Some patients with severe asthma may benefit from treatment with biologics, but evidence has been mostly collected from randomized controlled trials (RCTs), in which patients' characteristics are different from those encountered in asthma patients in the real-world setting. The aim of this study was to describe the clinical features of complete responders versus non-complete responders to long-term treatment with biologics in patients with severe asthma attended in routine daily practice.

METHODS

Data of a cohort of 90 patients with severe asthma who were treated with biologics (omalizumab, benralizumab, and mepolizumab) for at least 12 months and were followed up to March 2022. Data recorded included clinical characteristics and effectiveness of treatment (exacerbation, Asthma Control Test [ACT] score, lung function, use of maintenance oral corticosteroids [mOCS]), FeNO, and blood eosinophils at baseline, at 12 months, and at the end of follow-up. Complete response is considered if, in addition to not presenting exacerbations or the use of mOCS, the ACT score was >20 and, the FEV1 >80% predicted.

RESULTS

An improvement in all asthma control parameters was observed after 12 months of treatment and a mean follow-up of 55 months. After 12 months of treatment 27.2% of patients met the criteria of complete response and this percentage even increased to 35.3% at the end of follow-up. Long-term complete response was associated to better lung function with mepolizumab and omalizumab treatment and to less previous exacerbations in the benralizumab group. The main cause of not achieving a complete response was the persistence of an airflow obstructive pattern.

CONCLUSIONS

This study shows that omalizumab, benralizumab, and mepolizumab improved the clinical outcomes of patients with severe asthma in a clinic environment with similar effect sizes to RCTs in the long term follow-up. Airflow obstruction, however, was a predictor of a non-complete response to biologics.

Londrina Activities of Daily Living Protocol: validity, reliability, minimal detectable change, and standard error of measurement in adults with asthma

INTRODUCTION

Asthma symptoms are dyspnea, chronic cough, wheezing, chest tightness, or chest discomfort, which can directly limit the activities of daily living (ADL), which is frequently reported by adults with asthma. Evaluating ADL with a reliable protocol at the usual speed is necessary.

OBJECTIVES

To investigate the validity, reliability, minimal detectable change (MDC), and standard error of measurement (SEM) of the Londrina ADL Protocol (LAP) for adults with asthma.

METHODS

Adults with asthma were evaluated with the LAP test. Spearman's correlation coefficient was used to verify validity with the 6-min walk test (6MWT), Glittre-ADL test, and London Chest Activity of Daily Living (LCADL). To test the reliability, the test was reapplied in at least 30 min; the Wilcoxon test and Intraclass Correlation Coefficient (ICC), SEM, MDC, and learning effect were performed.

RESULTS

Fifty-three individuals were included (26% men, 43 ± 15 years, BMI 28 ± 8 kg/m2, FEV1 70 ± 24%predicted). For convergent validity, the LAP test was correlated with the 6MWT, Glittre-ADL, and LCADL scale (r = -0.49, 0.71, and 0.30, respectively; p < 0.03). There was a difference in test-retest (p < 0.0001) and reliability analysis shows ICC3 of 0.94, SEM of 14.88 s (22%), and MDC of 41.23 s (15%). Furthermore, the individuals performed the second test with -23 ± 19 (7.9%) s.

CONCLUSION

The LAP test is valid and reliable for assessing limitations during ADL in adults with asthma. Considerable learning effect was observed, therefore, the best of two measures may avoid underestimation.

Understanding Comorbidities of Respiratory Models as Novel Platforms for Drug Discovery

Chronic respiratory diseases affect over 450 million people worldwide and result in 4 million deaths per year. The majority of lung diseases are treated with drugs delivered directly to the lungs. However, there is bidirectional crosstalk between the lung and other organs/tissues in health and disease. This crosstalk supports targeting of extrapulmonary sites in addition to the lung to improve the comorbidities associated with lung disease. However, new preclinical in vivo and in vitro assays that model the human pathophysiology are required. In this review, we showcase the latest knowledge of the bidirectional relationship between the respiratory system and organs affected by comorbidities such as obesity and atherosclerosis. We also discuss the impact of new cell culture systems, including complex 3D culture models that may be used as platforms to generate disease insights and for drug discovery. This review highlights work presented by Respiratory and Inflammation Special Interest Group researchers as part of the Australasian Society of Clinical and Experimental Pharmacologists and Toxicologists (ASCEPT) annual scientific meeting in 2023.

An interpretable cluster-based logistic regression model, with application to the characterization of response to therapy in severe eosinophilic asthma

Asthma is a disease characterized by chronic airway hyperresponsiveness and inflammation, with signs of variable airflow limitation and impaired lung function leading to respiratory symptoms such as shortness of breath, chest tightness and cough. Eosinophilic asthma is a distinct phenotype that affects more than half of patients diagnosed with severe asthma. It can be effectively treated with monoclonal antibodies targeting specific immunological signaling pathways that fuel the inflammation underlying the disease, particularly Interleukin-5 (IL-5), a cytokine that plays a crucial role in asthma. In this study, we propose a data analysis pipeline aimed at identifying subphenotypes of severe eosinophilic asthma in relation to response to therapy at follow-up, which could have great potential for use in routine clinical practice. Once an optimal partition of patients into subphenotypes has been determined, the labels indicating the group to which each patient has been assigned are used in a novel way. For each input variable in a specialized logistic regression model, a clusterwise effect on response to therapy is determined by an appropriate interaction term between the input variable under consideration and the cluster label. We show that the clusterwise odds ratios can be meaningfully interpreted conditional on the cluster label. In this way, we can define an effect measure for the response variable for each input variable in each of the groups identified by the clustering algorithm, which is not possible in standard logistic regression because the effect of the reference class is aliased with the overall intercept. The interpretability of the model is enforced by promoting sparsity, a goal achieved by learning interactions in a hierarchical manner using a special group-Lasso technique. In addition, valid expressions are provided for computing odds ratios in the unusual parameterization used by the sparsity-promoting algorithm. We show how to apply the proposed data analysis pipeline to the problem of sub-phenotyping asthma patients also in terms of quality of response to therapy with monoclonal antibodies.

Obesity and Asthma: Implementing a Treatable Trait Care Model

Recognition of obesity as a treatable trait of asthma, impacting its development, clinical presentation and management, is gaining widespread acceptance. Obesity is a significant risk factor and disease modifier for asthma, complicating treatment. Epidemiological evidence highlights that obese asthma correlates with poorer disease control, increased severity and persistence, compromised lung function and reduced quality of life. Various mechanisms contribute to the physiological and clinical complexities observed in individuals with obesity and asthma. These encompass different immune responses, including Type IVb, where T helper 2 cells are pivotal and driven by cytokines like interleukins 4, 5, 9 and 13, and Type IVc, characterised by T helper 17 cells and Type 3 innate lymphoid cells producing interleukin 17, which recruits neutrophils. Additionally, Type V involves immune response dysregulation with significant activation of T helper 1, 2 and 17 responses. Finally, Type VI is recognised as metabolic-induced immune dysregulation associated with obesity. Body mass index (BMI) stands out as a biomarker of a treatable trait in asthma, readily identifiable and targetable, with significant implications for disease management. There exists a notable gap in treatment options for individuals with obese asthma, where asthma management guidelines lack specificity. For example, there is currently no evidence supporting the use of incretin mimetics to improve asthma outcomes in asthmatic individuals without Type 2 diabetes mellitus (T2DM). In this review, we advocate for integrating BMI into asthma care models by establishing clear target BMI goals, promoting sustainable weight loss via healthy dietary choices and physical activity and implementing regular reassessment and referral as necessary.

Real-world phenotyping and risk assessment of childhood asthma burden using national registries

BACKGROUND

Phenotype classification contributes to risk assessment of asthma. Previous studies have applied this concept primarily to adult populations and in the setting of research protocol assessments which may not be applicable to clinical settings.

OBJECTIVE

Exploring the value of routinely collected clinical data for phenotype classification and risk assessment of childhood asthma.

METHODS

Using hospital and laboratory data, 29,851 children in a Danish nationwide database aged 2-17 years with ICS-treated asthma in 2015 followed for two years (730 days) were classified to have T2 (elevated blood eosinophils (>300 cells/μL) and/or elevated total- or specific-IgE), and/or non-T2 risk factors (in utero tobacco exposure and/or severe viral infections). Logistic regression was applied to quantify associations of risk factors with asthma severity, control, and exacerbation risk.

RESULTS

In a complete case analysis, 85.8 % children had at least one T2 risk factor and 29.3 % had mixed T2/non-T2 risk factors. Elevated blood eosinophils and total/specific IgE were associated with exacerbations (ORs 1.55 (1.38-1.73) and 1.41 (1.20-1.66) and higher asthma severity (1.42 (1.24-1.63) and 1.31 (1.08-1.60)), respectively. Dose-dependency was observed between blood eosinophil counts, total IgE levels, and risk of adverse outcomes. Furthermore, accumulation of risk factors demonstrated an increasing risk, with children with all four risk factors having a high risk of any adverse asthma-related outcome (OR 3.13 (2.03-4.82) CONCLUSION: Asthma phenotypic markers defined in research protocols can be reliably applied in real-world settings by utilizing data collected during routine clinical care and enable better classification of risk of adverse asthma outcomes.

Effects of menopause and fat mass in asthmatic inflammation

INTRODUCTION

Female hormones and obesity have an impact on women with asthma. We aimed to describe how these components affect asthma inflammatory processes.

METHODS

Sex hormones [FSH, LH, estradiol (E2), estrone (E1), testosterone and Δ4 androstenedione (A4)] and serum IL1β, IL13, IL17a, IL-5, IL6, TNF-a were measured from 11 to18 pre- and postmenopausal women with asthma.

RESULTS

Premenopausal normal weight women revealed higher levels of IL5 and IL17a than obese women on both days of the menstrual cycle (IL5: D1: 6.4 vs 1.4 pg/ml, p = .036 and D14: 3 vs 1.4 pg/ml, p = .045 and IL17a: D1: 13.7 pg/ml vs 10.6 pg/ml and D14: 12.4 pg/ml vs 10.6 pg/ml, p = .009, respectively). In premenopausal women on D1, Δ4 Androstenedione was positively correlated with IL1β (p = .016, r = 0.733), whereas on D14, Estradiol with IL1β (p = .009, r = -.768) and TNF-a with Testosterone (p = .004, r = -0.816), and Δ4 Androstenedione (p = .002, r = -0.841) negatively. In postmenopausal women, TNF-a was negatively associated with FSH (p = .004, r = -0.638), but positively with Testosterone (p = .025, r = 0.526) and IL10 also positively with Estradiol (p = .007, r = 0.610).

CONCLUSION

Obesity shows a protective role in asthma through the suppression of IL5 and IL17. Estrogens seem to inhibit Th1 and Th2 inflammation, while androgens have a dual role with negative and positive correlations with neutrophilic biomarkers.

Exploring CD26-/lo subpopulations of lymphocytes in asthma phenotype and severity: A novel CD4+ T cell subset expressing archetypical granulocyte proteins

BACKGROUND

Asthma pathology may induce changes in naïve/memory lymphocyte proportions assessable through the evaluation of surface CD26 (dipeptidyl peptidase 4/DPP4) levels. Our aim was to investigate the association of asthma phenotype/severity with the relative frequency of CD26-/lo, CD26int and CD26hi subsets within different lymphocyte populations.

METHODS

The proportion of CD26-/lo, CD26int and CD26hi subsets within CD4+ effector T cells (Teff), total CD4- lymphocytes, γδ-T cells, NK cells and NKT cells was measured in peripheral blood samples from healthy (N = 30) and asthma (N = 119) donors with different phenotypes/severities by flow cytometry. We performed K-means clustering analysis and further characterised the CD4+CD26-/lo Teff cell subset by LC-MS/MS and immunofluorescence.

RESULTS

Cluster analysis including clinical and flow cytometry data resulted in four groups, two of them with opposite inflammatory profiles (neutrophilic vs. eosinophilic). Neutrophilic asthma presented reduced CD4-CD26hi cells, which negatively correlated with systemic inflammation. Eosinophilic asthma displayed a general expansion of CD26-/lo subsets. Specifically, CD4+CD26-/lo Teff expansion was confirmed in asthma, especially in atopic patients. Proteomic characterisation of this subset with a TEM/TEMRA phenotype revealed upregulated levels of innate (e.g. MPO and RNASE2) and cytoskeleton/extracellular matrix (e.g. MMP9 and ACTN1) proteins. Immunofluorescence assays confirmed the presence of atypical proteins for CD4+ T cells, and an enrichment in 'flower-like' nuclei and MMP9/RNASE2 levels in CD4+CD26-/lo Teff compared to CD4+ T lymphocytes.

CONCLUSION

There is an association between CD26 levels in different lymphocyte subsets and asthma phenotype/severity. CD4+CD26-/loTEMRA cells expressing innate proteins specific to eosinophils/neutrophils could be determinant in sustaining long-term inflammation in adult allergic asthma.

Symptom phenotyping in people with cystic fibrosis during acute pulmonary exacerbations using machine-learning K-means clustering analysis

INTRODUCTION

People with cystic fibrosis (PwCF) experience frequent symptoms associated with chronic lung disease. A complication of CF is a pulmonary exacerbation (PEx), which is often preceded by an increase in symptoms and a decline in lung function. A symptom cluster is when two or more symptoms co-occur and are related; symptom clusters have contributed meaningful knowledge in other diseases. The purpose of this study is to discover symptom clustering patterns in PwCF during a PEx to illuminate symptom phenotypes and assess differences in recovery from PExs.

METHODS

This study was a secondary, longitudinal analysis (N = 72). Participants at least 10 years of age and being treated with intravenous antibiotics for a CF PEx were enrolled in the United States. Symptoms were collected on treatment days 1-21 using the CF Respiratory Symptom Diary (CFRSD)-Chronic Respiratory Symptom Score (CRISS). K-means clustering was computed on day 1 symptom data to detect clustering patterns. Linear regression and multi-level growth models were performed.

RESULTS

Symptoms significantly clustered based on severity: low symptom (LS)-phenotype (n = 42), high symptom (HS)-phenotype (n = 30). HS-phenotype had worse symptoms and CRISS scores (p< 0.01) than LS-phenotype. HS-phenotype was associated with spending 5 more nights in the hospital annually (p< 0.01) than LS-phenotype. HS-phenotype had worse symptoms over 21 days than LS-phenotype (p< 0.0001).

CONCLUSION

Symptoms significantly cluster on day 1 of a CF-PEx. PwCF with HS-phenotype spend more nights in the hospital and are less likely to experience the same resolution in symptoms by the end of PEx treatment than LS-phenotype.

Anti-interleukin-5/anti-interleukin-5 receptor α treatment improves self-reported work productivity in patients with severe eosinophilic asthma: a prospective cohort trial

Background

Severe asthma affects the working life of millions of people worldwide. Interleukin (IL)-5/anti-interleukin-5 receptor α (IL-5Rα) antibodies are highly effective in reducing symptoms in patients with severe eosinophilic asthma. We analysed effects of anti-IL-5/anti-IL-5Rα treatment on self-reported productivity and absenteeism at work in patients with severe eosinophilic asthma.

Methods

In this prospective single-centre study, patients with severe eosinophilic asthma received a questionnaire assessing their actual occupational status and the influence asthma has on their work life, productivity and missed days at work prior to initiation of antibody treatment and after 6 and 12 months of therapy. Among others, the Work Productivity and Activity Impairment Questionnaire: Specific Health Problem (WPAI:SHP) was used.

Results

Out of 54 patients with a median age of 60 years, 27 (50%) were employed. In addition to an increase in asthma control and lung function, self-reported productivity increased significantly with a decrease on the WPAI:SHP from 30% (interquartile range (IQR) 20-50%) to 10% (IQR 0-27.5%) under treatment (p=0.001). Furthermore, self-reported missed days at work were reduced from 2 days·month-1 (IQR 1.75-6 days·month-1) to 0 days·month-1 (IQR 0-2 days·month-1; p=0.067). At baseline 22 employed patients (81%) stated they were affected at work by their asthma. After 12 months of treatment, this number decreased to eight patients (30%; p=0.038).

Conclusions

This prospective analysis could prove the substantial impact severe asthma has on patients' working life. Anti-IL-5/anti-IL-5Rα treatment in patients with severe eosinophilic asthma leads to a significant increase in self-reported productivity at work, and after 12 months of treatment patients state substantially fewer negative effects on their working situation.

Targeting Lipid Metabolism in Obese Asthma: Perspectives and Therapeutic Opportunities

BACKGROUND

Obese asthma represents a unique phenotype of asthma characterized by severe symptoms, poor medication controls, increased frequency of exacerbations, and an overall diminished quality of life. Numerous factors, including the complex interactions between environment, mechanical processes, inflammatory responses, and metabolites disturbance, contribute to the onset of obese asthma.

SUMMARY

Notably, multiple metabolomics studies in the last several years have revealed the significant abnormalities in lipid metabolism among obese asthmatic patients. Several bioactive lipid messengers participate in the development of obese asthma has also been observed. Here, we present and discuss the latest advances regarding how bioactive lipid molecules contribute to the pathogenic process and mechanisms underlying obese asthma. The key roles of potentially significant effector cells and the pathways by which they respond to diverse lipid metabolites are also described. We finally summarize current lipid-related therapeutic options for the treatment of obese asthma and discuss their application prospects.

KEY MESSAGES

This review underscores the impacts of abnormal lipid metabolism in the etiopathogenesis of obese asthma and asks for further investigation to elucidate the intricate correlations among lipids, obesity, and asthma.

Asthma and hypertension: the role of airway inflammation

Introduction

Asthma is a chronic inflammatory respiratory disease often associated with comorbidities. Among cardiovascular comorbidities, arterial hypertension seems to create an additional health burden in asthmatics. However, evidence on this relationship is lacking.

Objective

Our study aims to evaluate the characteristics of hypertensive asthmatics, focusing on the role of inflammation as a possible link between these diseases.

Methods

We conducted a monocentric retrospective analysis consecutively including asthmatics who underwent induced sputum (IS) at our asthma referral center. Patients were divided in two groups according to presence or absence of history of hypertension. Clinical, functional, and inflammatory (airway and systemic) data were collected.

Results

Data on two hundred and sixty asthmatic patients were analyzed. Seventy-nine (30.4%) of them had a diagnosis of hypertension requiring a specific pharmacological treatment. Asthmatics with hypertension were more frequently male (p = 0.047), older (p < 0.001), and with higher body max index (BMI) (p < 0.001) when compared to normotensive patients. No difference concerning asthma control, severity and pharmacological treatment was observed between the two groups (all p > 0.05); distribution of comorbidities and lung function impairment (forced expiratory volume in the first second (FEV1) and forced vital capacity (FVC); all p < 0.05) were statistically different between groups. Mixed granulocytic airway inflammation was prevalent in the hypertensive asthmatics (p = 0.014). Interestingly, a multivariable analysis revealed that age ≥ 65 years and an increased percentage of sputum neutrophils (≥61%) were independent predictors of hypertensive status (p < 0.001).

Conclusion

Our data suggest that neutrophilic airway inflammation (as evaluated by induced sputum) is strictly associated with hypertension. In clinical practice, phenotyping asthmatic patients with comorbidities like hypertension could be useful also from a therapeutic point of view. Additional studies are mandatory to further elucidate the role of neutrophilic airway inflammation in asthma with cardiovascular diseases.

Reduced Effectiveness of Anti-IgE Treatment Among Adults with Severe Asthma with Older Age of Asthma Onset: Results from the CHRONICLE Study

Purpose

Younger age of asthma onset (AAO) has been associated with an allergic phenotype, whereas eosinophilic phenotypes have been associated with older AAO. In randomized trials, biologic efficacy among adults with severe asthma (SA) has varied by age at asthma onset. To determine whether these associations observed in trials apply to real-world outcomes, this study examined biologic effectiveness by AAO and biologic class in a large, real-world cohort.

Patients and methods

CHRONICLE is an ongoing, real-world study of US adults with subspecialist-treated SA receiving biologics, maintenance corticosteroids, or who are uncontrolled on high-dosage inhaled corticosteroids with additional controllers. Patients enrolled between February 2018 and February 2022 who initiated a biologic for SA and had complete data for analysis were included. A locally estimated scatterplot smoothing (LOESS) analysis was used to plot the relationship between percentage exacerbation rate reduction and AAO by biologic class.

Results

Of 578 patients with complete data, 198, 149, and 231 were diagnosed with asthma at age <18, 18-39, and ≥40 years, respectively. Across subgroups, patients were predominantly White (72-78%), female (67-73%), and commercially insured (54-71%). In the LOESS analysis, exacerbation rate reductions were similar for anti-IgE and anti-IL-5/5R and anti-IL-4R subgroups with younger AAO, but the exacerbation rate reduction diminished for patients with older AAO receiving anti-IgE therapy, particularly with asthma onset age ≥40 years.

Conclusion

Clinicians should consider age of onset in biologic treatment decisions, given reduced effectiveness of omalizumab in patients with asthma onset at age ≥40 years.

Clinicaltrialsgov Identifier

NCT03373045.

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.

Understanding the impact of breathing pattern disorders in difficult-to-treat asthma

INTRODUCTION

Difficult-to-treat asthma is defined as asthma that is uncontrolled despite high-level treatment or requires such treatment to maintain good control and reduce exacerbations. Breathing pattern disorders (BPD) have been reported as a comorbidity in ~ 24-42% % of patients with difficult-to-treat asthma. This narrative review will assess the association, impact, and management of BPD in difficult-to-treat asthma.

AREAS COVERED

We outline current understandings of the nature of difficult-to-treat asthma and BPD. We then review the impact of BPD on difficult-to-treat asthma and Multidisciplinary Team (MDT) approaches to assessing and managing BPD in this patient group. A comprehensive literature search was performed by an asthma specialist MDT including physiotherapists, psychologists, and physicians to create a holistic perspective on this subject.

EXPERT OPINION

BPD exerts significant negative impacts across multiple domains in patients with difficult-to treat asthma. There is a need for further observational, interventional, qualitative and quantitative research to develop better diagnosis, treatment, and awareness of the impacts of BPD including health economic analysis. Studies should develop multimodal approaches that better treat both BPD and associated comorbidities within the multimorbidity framework of difficult-to-treat asthma. Recognizing and addressing BPD should be key elements in future difficult-to-treat asthma management guidelines and clinical practice.

Multivariate Cluster Analyses to Characterize Asthma Heterogeneity and Benralizumab Responsiveness

BACKGROUND

An improved understanding of how severe asthma heterogeneity affects response could inform treatment decisions.

OBJECTIVES

Characterize heterogeneity and benralizumab responsiveness in patients grouped by predefined Severe Asthma Research Program clusters using a multivariate approach.

METHODS

In post-hoc analyses of the randomized, double-blind, placebo-controlled phase III SIROCCO (NCT01928771) and CALIMA (NCT01914757) studies, patients with severe asthma who received benralizumab or placebo were assigned to clusters using an established discriminant function to analyze 11 clinical characteristics simultaneously. The annualized asthma exacerbation rate, exacerbation incidence, and lung function were analyzed across clusters.

RESULTS

Patients (n = 2,281) met criteria for four of five clusters: cluster 2 (early-onset moderate asthma, n = 393), cluster 4 (early-onset severe asthma, n = 386), cluster 3 (late-onset severe asthma, n = 641), and cluster 5 (late-onset severe, obstructed asthma, n = 861); no patients met cluster 1 criteria. Exacerbation rate reductions were significant in late-onset severe asthma (-48% [95% CI, -61% to -31%]; P < .0001) and late-onset severe, obstructed asthma (-50% [95% CI, -59% to -38%]; P < .0001), with nonsignificant reductions in early-onset clusters. These differences could not be fully explained by blood eosinophil count differences. Values for improvements in FEV1 were significant in late-onset severe asthma (+133 mL [95% CI, 66-200]; P = .0001) and late-onset severe, obstructed asthma (+160 mL [95% CI, 85-235]; P < .0001) while maintaining acute bronchodilator responsiveness.

CONCLUSIONS

Benralizumab reduced exacerbations and improved lung function, primarily in late-onset asthma clusters. This multivariate approach to identify subphenotypes, potentially reflecting pathobiological mechanisms, can guide therapy beyond univariate approaches.

Immediate and One-Year Outcomes of an Asthma-Tailored Pulmonary Rehabilitation Programme in Overweight and Obese People with Difficult-to-Treat Asthma

Introduction

Management of difficult-to-treat asthma is particularly challenging in people with elevated body mass index (BMI). Our randomised controlled trial of pulmonary rehabilitation (PR) showed improved outcomes at 8 weeks. Here we assess immediate and one-year effects of asthma-tailored PR in participants with difficult-to-treat asthma and BMI ≥25 kg/m2, and identify response predictors.

Methods

A prospective observational study of PR, tailored to asthma, comparing outcomes at baseline (V1), immediately after 8 weeks of PR (V2), and at 1 year (V3). Baseline characteristics were compared in responders/non-responders defined by achievement of minimum clinically important difference (MCID) for asthma control questionnaire (ACQ6) (0.5) at 8 weeks and 1 year.

Results

Of 92 participants, 56 attended V2 and 45 attended V3. Mean age was 60 (SD 13) years, 60% were female, and median (IQR) BMI was 33.8 (29.5-38.7) kg/m2. At V1, V2, and V3, respectively, there were significant differences in ACQ6 (mean (95% CI): 2.5 (2.1-2.9), 2.2 (1.8-2.5), and 2.3 (1.9-2.7), p<0.003), Borg breathlessness score post-6-minute walk test (median (IQR): 2 (0.5-3), 1 (0-2), and 1 (0.5-2), p<0.035), and annualised exacerbations requiring prednisolone (median (IQR): 3 (2-5), 0 (0-4.7), and 1.5 (0-4.2), p<0.003). A total of 27/56 (48%) had improvements >MCID for ACQ6 at V2 and 16 (33%) at V3. Participants with higher ACQ6 scores at baseline (suggesting poorer asthma control) were more likely to achieve MCID. Baseline BMI, within the range studied, was not predictive.

Conclusion

Pulmonary rehabilitation induced improvements in asthma-related outcomes including perception of breathlessness, asthma control, and exacerbation frequency at 1 year. Those with poorer baseline asthma control were more likely to benefit.

Clinical remission and control in severe asthma: agreements and disagreements

Over the last two decades, we have witnessed great advancements in our understanding of the immunological pathways of asthma, leading to the development of targeted therapies, such as biologic drugs, that have radically and definitively changed the clinical outcomes of severe asthma. Despite the numerous therapeutic options available, ~4-10% of all people with asthma have severe or uncontrolled asthma, associated with an increased risk of developing chronic oral corticosteroid use, fixed airflow limitation, exacerbations, hospitalization and, finally, increased healthcare costs. The new concept of disease modification in asthma comes from the evolution of asthma management, which encompasses phenotyping patients with different inflammatory endotypes characterizing the disease, followed by the advent of more effective therapies capable of targeting the proximal factors of airway inflammation. This treat-to-target approach aims to achieve remission of the disease. Because the novel treatment paradigm for severe asthma with the advent of biologic therapies is no longer clinical control but rather clinical remission - a step closer to the concept of cure - a deeper and more accurate understanding of the critical causal mechanisms and endotypes of asthma is necessary to achieve the goal of clinical remission, which has the potential to generate real life-changing benefits for patients. This review aims to frame the evolution of the debated concept of clinical remission and provide clinicians with insights that may be helpful in achieving remission in the greatest number of patients.

Bibliometric Insights into Research Hotspots and Trends in Obesity and Asthma from 2013 to 2023

INTRODUCTION

Obesity and asthma are closely linked, but the current state of research on this topic and future research directions have yet to be comprehensively explored. This study aims to provide an up-to-date overview of the research landscape in the field of obesity and asthma.

METHODS

A bibliometric analysis was conducted using the Web of Science Core Collection database to identify papers published on obesity and asthma between 2013 and 2023. VOSviewer software was utilized for statistical analysis and visualization of collaborative networks, research trends, literature sources, citation analysis, co-citation analysis, and keyword analysis.

RESULTS

A total of 3,406 records from 1,010 journals authored by 17,347 researchers affiliated with 4,573 institutes across 117 countries and regions were retrieved. The number of publications and citations increased annually. The USA and China contributed the majority of records. Major nodes in the collaboration network map included Harvard Medical School, Johns Hopkins University, University of Newcastle, Karolinska Institution, University of Toronto, and Seoul National University. Prolific authors included Anne E. Dixon, Erick Forno, Lisa G. Wood, Deepa Rastogi, and Fernando Holguin. Research trends and hotspots focused on metabolism studies, Mendelian randomization, gut microbiome, inflammation response, gene, biomarker research, and comorbidities were identified as potential future research frontiers.

CONCLUSION

This study provides a comprehensive overview of the current research status and trends in the field of obesity and asthma. Our findings highlight the importance of understanding collaboration patterns, research hotspots, and emerging frontiers to guide future research in this area.

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.

Withaferin A reduces pulmonary eosinophilia and IL-25 production in a mouse model of allergic airways disease

Several studies report that ashwagandha, a traditional Ayurvedic supplement, has anti-inflammatory properties. Type 2 (T2) asthma is characterized by eosinophilic airway inflammation. We hypothesized that allergen-induced eosinophilic airway inflammation in mice would be reduced following administration of Withaferin A (WFA), the primary active phytochemical in Ashwagandha. C57BL/6J mice were given 10 total intra-peritoneal injections of 2 mg/kg WFA or vehicle control, concurrent with 6 total intranasal administrations of 50 μg house dust mite extract (HDM) or saline control over 2 weeks. We observed that treatment with WFA reduced allergen-induced peribronchial inflammation and airway eosinophil counts compared to mice treated with controls. In addition, we observed that treatment with WFA reduced lung levels of interleukin-25 (IL-25) but increased lung gene expression levels of its co-receptor, Il17ra, in HDM-challenged mice compared to HDM-challenged mice that received the vehicle control. This study pinpoints a potential mechanism by which WFA modulates allergen-induced airway eosinophilia via the IL-25 signaling pathway. Future studies will investigate the effects of WFA administration on lung eosinophilia and IL-25 signaling in the context of chronic allergen-challenge.

Lower skeletal muscle density and airway structure on computed tomography in asthma

BACKGROUND

Lower skeletal muscle density may reflect muscle adiposity and metabolic dysregulation that potentially impair disease control and lung function independent of high body mass index (BMI) in patients with asthma.

OBJECTIVE

To investigate whether the lower density of pectoralis muscles (PMs) and erector spinae muscles (ESMs) on chest computed tomography was associated with airway structural changes in patients with asthma.

METHODS

Consecutive patients with asthma and healthy controls undergoing chest computed tomography were retrospectively analyzed. The ESM and PM density, areas of subcutaneous adipose tissue near the PM and epicardial adipose tissue, wall area percent of the airways, and airway fractal dimension (AFD) were quantified on computed tomography.

RESULTS

The study included 179 patients with asthma (52% women) and 88 controls (47% women). All the controls were 60 years old or younger. The PM and ESM density in female patients with asthma who were 60 years old or younger were significantly lower than those in controls after adjustment for BMI. In female patients with asthma at all ages, lower PM and ESM density (but not subcutaneous or epicardial adipose tissue area) was associated with greater wall area percent of the airways and lower AFD after adjusting for age, height, BMI, smoking status, blood eosinophil count, and oral corticosteroid use. The only association between ESM density and AFD was found in male patients with asthma.

CONCLUSION

Lower skeletal muscle density may be associated with airway wall thickening and less complexity of the airway luminal tree in female patients with asthma.

The Path to Diagnosis of Severe Asthma-A Qualitative Exploration

Purpose

Severe asthma poses a significant health burden in those with the disease, therefore a timely diagnosis can ensure patients receive specialist care and appropriate medication management. This study qualitatively explored the patient experience of adult Australians with severe asthma regarding specialist referral, to identify potential opportunities to streamline the process of severe asthma diagnosis and treatment and optimise referral pathways.

Patients and Methods

Adults currently being treated with medication for severe asthma were invited to participate in this study. Participants were interviewed and asked to describe initial diagnosis of their asthma or severe asthma, and how they came to be referred to secondary care. Interviews were transcribed verbatim, coded by two members of the research team and thematically analysed.

Results

Thirty-two people completed the study; 72% were female. Mean interview length was 33 minutes. The major themes generated were patient-related factors contributing to seeking a severe asthma diagnosis; perceptions of health care provision; diagnosis of severe asthma and the referral journey. Key findings were that both patient and healthcare provider attitudes contributed to participants' willingness to seek or receive a referral, and referral to respiratory specialists was often delayed. Contributing factors included a mismatch between patient expectations and general practice, lack of continuity of primary care, and a lack of patient understanding of the role of the respiratory specialist.

Conclusion

Timely severe asthma diagnosis in Australia appears to be hampered by an absence of a clear referral process, lack of general practitioner (GP) knowledge of additional treatment options, underutilisation of pharmacists, and multiple specialists treating patient comorbidities. Directions for future research might include interviewing healthcare providers regarding how well the referral process works for severe asthma patients, and researching the time between referral and when a patient sees the respiratory specialist.

Novel Machine Learning Identifies 5 Asthma Phenotypes Using Cluster Analysis of Real-World Data

BACKGROUND

Asthma classification into different subphenotypes is important to guide personalized therapy and improve outcomes.

OBJECTIVES

To further explore asthma heterogeneity through determination of multiple patient groups by using novel machine learning (ML) approaches and large-scale real-world data.

METHODS

We used electronic health records of patients with asthma followed at the Cleveland Clinic between 2010 and 2021. We used k-prototype unsupervised ML to develop a clustering model where predictors were age, sex, race, body mass index, prebronchodilator and postbronchodilator spirometry measurements, and the usage of inhaled/systemic steroids. We applied elbow and silhouette plots to select the optimal number of clusters. These clusters were then evaluated through LightGBM's supervised ML approach on their cross-validated F1 score to support their distinctiveness.

RESULTS

Data from 13,498 patients with asthma with available postbronchodilator spirometry measurements were extracted to identify 5 stable clusters. Cluster 1 included a young nonsevere asthma population with normal lung function and higher frequency of acute exacerbation (0.8 /patient-year). Cluster 2 had the highest body mass index (mean ± SD, 44.44 ± 7.83 kg/m2), and the highest proportion of females (77.5%) and Blacks (28.9%). Cluster 3 comprised patients with normal lung function. Cluster 4 included patients with lower percent of predicted FEV1 of 77.03 (12.79) and poor response to bronchodilators. Cluster 5 had the lowest percent of predicted FEV1 of 68.08 (15.02), the highest postbronchodilator reversibility, and the highest proportion of severe asthma (44.9%) and blood eosinophilia (>300 cells/μL) (34.8%).

CONCLUSIONS

Using real-world data and unsupervised ML, we classified asthma into 5 clinically important subphenotypes where group-specific asthma treatment and management strategies can be designed and deployed.

Pathobiological signatures of dysbiotic lung injury in pediatric patients undergoing stem cell transplantation

Hematopoietic cell transplantation (HCT) uses cytotoxic chemotherapy and/or radiation followed by intravenous infusion of stem cells to cure malignancies, bone marrow failure and inborn errors of immunity, hemoglobin and metabolism. Lung injury is a known complication of the process, due in part to disruption in the pulmonary microenvironment by insults such as infection, alloreactive inflammation and cellular toxicity. How microorganisms, immunity and the respiratory epithelium interact to contribute to lung injury is uncertain, limiting the development of prevention and treatment strategies. Here we used 278 bronchoalveolar lavage (BAL) fluid samples to study the lung microenvironment in 229 pediatric patients who have undergone HCT treated at 32 children's hospitals between 2014 and 2022. By leveraging paired microbiome and human gene expression data, we identified high-risk BAL compositions associated with in-hospital mortality (P = 0.007). Disadvantageous profiles included bacterial overgrowth with neutrophilic inflammation, microbiome contraction with epithelial fibroproliferation and profound commensal depletion with viral and staphylococcal enrichment, lymphocytic activation and cellular injury, and were replicated in an independent cohort from the Netherlands (P = 0.022). In addition, a broad array of previously occult pathogens was identified, as well as a strong link between antibiotic exposure, commensal bacterial depletion and enrichment of viruses and fungi. Together these lung-immune system-microorganism interactions clarify the important drivers of fatal lung injury in pediatric patients who have undergone HCT. Further investigation is needed to determine how personalized interpretation of heterogeneous pulmonary microenvironments may be used to improve pediatric HCT outcomes.

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).

Real-World Evaluation of Asthma Severity Following Endoscopic Sinus Surgery in Chronic Rhinosinusitis Patients

Objective

This study aimed to evaluate the impact of endoscopic sinus surgery (ESS) on asthma severity up to 12 months after surgical intervention.

Study Design

Retrospective cohort.

Setting

Tertiary care center.

Methods

Patients with a history of asthma and Chronic Rhinosinusitis (CRS) who underwent ESS between 2013 and 2023 were included. Asthma severity was assessed according to current Global Initiative for Asthma (GINA) guidelines, classifying patients into mild, moderate, and severe based on medication requirements. Asthma severity was evaluated up to 3 months prior to ESS and 1-year post-ESS. Patients with aspirin-exacerbated respiratory disease (AERD) were excluded. Statistical analysis was performed using McNemar test and Wilcoxon signed-rank test to assess differences in asthma severity, medication doses, and number of medications.

Results

Sixty-five patients were included, of which 44 (67.7%) had CRS with nasal polyps (CRSwNP) and 21 (32.3%) had CRS without nasal polyps (CRSsNP). No significant differences were found in asthma severity pre- and post-ESS (P = .175). Similarly, no differences were found in ICS doses (P = .999), total number of prescribed medications (P = .157) or presence of exacerbations before and after ESS (P = .078). However, a significant increase in time from last rescue inhaler use was noted after ESS, increasing from a median of 6.71 to 23.1 weeks (P = .004).

Conclusion

This study is the first to assess the impact of ESS on asthma severity in a real-world setting. Our findings suggest that ESS does not impact asthma severity classification. However, it might provide relief of asthma symptoms in the early postoperative period.

Activated non-neuronal cholinergic system correlates with non-type 2 inflammation and exacerbations in severe asthma

BACKGROUND

Non-neuronal cholinergic system (NNCS) contributes to various inflammatory airway diseases. However, the role of NNCS in severe asthma (SA) remains largely unexplored.

OBJECTIVE

To explore airway NNCS in SA.

METHODS

In this prospective cohort study based on the Australasian Severe Asthma Network in a real-world setting, patients with SA (n = 52) and non-SA (n = 104) underwent clinical assessment and sputum induction. The messenger RNA (mRNA) levels of NNCS components and proinflammatory cytokines in the sputum were detected using real-time quantitative polymerase chain reaction, and the concentrations of acetylcholine (Ach)-related metabolites were evaluated using liquid chromatography coupled with tandem mass spectrometry. Asthma exacerbations were prospectively investigated during the next 12 months. The association between NNCS and future asthma exacerbations was also analyzed.

RESULTS

Patients with SA were less controlled and had worse airway obstruction, a lower bronchodilator response, higher doses of inhaled corticosteroids, and more add-on treatments. The sputum mRNA levels of NNCS components, such as muscarinic receptors M1R-M5R, OCT3, VACHT, and ACHE; proinflammatory cytokines; and Ach concentration in the SA group were significantly higher than those in the non-SA group. Furthermore, most NNCS components positively correlated with non-type (T) 2 inflammatory profiles, such as sputum neutrophils, IL8, and IL1B. In addition, the mRNA levels of sputum M2R, M3R, M4R, M5R, and VACHT were independently associated with an increased risk of moderate-to-severe asthma exacerbations.

CONCLUSION

This study indicated that the NNCS was significantly activated in SA, leading to elevated Ach and was associated with clinical features, non-T2 inflammation, and future exacerbations of asthma, highlighting the potential role of the NNCS in the pathogenesis of SA.

CLINICAL TRIAL REGISTRATION

ChiCTR-OOC-16009529 (http://www.chictr.org.cn).

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.

Abnormal saturated fatty acids and sphingolipids metabolism in asthma

Recent advances in fatty acid analysis have highlighted the links between lipid disruption and disease development. Lipid abnormalities are well-established risk factors for many of the most common chronic illnesses, and their involvement in asthma is also becoming clear. Here, we review research demonstrating the role of abnormal lipid metabolism in asthma, with a focus on saturated fatty acids and sphingolipids. High levels of palmitic acid, the most abundant saturated fatty acid in the human body, have been found in the airways of asthmatic patients with obesity, and were shown to worsen eosinophilic airway inflammation in asthma model mice on a high-fat diet. Aside from being a building block of longer-chain fatty acids, palmitic acid is also the starting point for de novo synthesis of ceramides, a class of sphingolipids. We outline the three main pathways for the synthesis of ceramides, which have been linked to the severity of asthma and act as precursors for the dynamic lipid mediator sphingosine 1-phosphate (S1P). S1P signaling is involved in allergen-induced eosinophilic inflammation, airway hyperresponsiveness, and immune-cell trafficking. A recent study of mice with mutations for the elongation of very long-chain fatty acid family member 6 (Elovl6), an enzyme that elongates fatty acid chains, has highlighted the potential role of palmitic acid composition, and thus lipid balance, in the pathophysiology of allergic airway inflammation. Elovl6 may be a potential therapeutic target in severe asthma.

Weighted Breaths: Exploring Biologic and Non-Biologic Therapies for Co-Existing Asthma and Obesity

PURPOSE OF REVIEW

To discuss the effectiveness of biologics, some of which comprise the newest class of asthma controller medications, and non-biologics in the treatment of asthma co-existing with obesity.

RECENT FINDINGS

Our review of recent preliminary and published data from clinical trials revealed that obese asthmatics respond favorably to dupilumab, mepolizumab, omalizumab, and tezepelumab, which are biologics currently indicated as add-on maintenance therapy for severe asthma. Furthermore, clinical trials are ongoing to assess the efficacy of non-biologics in the treatment of obese asthma, including a glucagon-like peptide-1 receptor agonist, a Janus kinase inhibitor, and probiotics. Although many biologics presently indicated as add-on maintenance therapy for severe asthma exhibit efficacy in obese asthmatics, other phenotypes of asthma co-existing with obesity may be refractory to these medications. Thus, to improve quality of life and asthma control, it is imperative to identify therapeutic options for all existing phenotypes of obese asthma.