Bronchial Thermoplasty Induced Airway Smooth Muscle Reduction and Clinical Response in Severe Asthma. The TASMA Randomized Trial

Efficacy of bronchial thermoplasty in a patient panel with uncontrolled severe persistent asthma

BACKGROUND

Bronchial thermoplasty (BT) is an approved procedure to manage uncontrolled severe persistent asthma. Many insurance providers are reluctant to pay for BT without proven benefit among their specific patient panel.

OBJECTIVE

Determine if BT is effective in a panel patient panel with uncontrolled severe persistent asthma.

STUDY DESIGN AND METHODS

This was an unblinded prospective study of adult subjects with uncontrolled severe persistent asthma who underwent BT. Outcomes were assessed at baseline and then 3-, 6-, 12-, 18- and 24-months post-BT. The primary metric was an improved Asthma Quality of Life Questionnaire (AQLQ) score. Other metrics included improved Asthma Control Test (ACT), peak expiratory flow rates (PEFR), spirometry, fractional excretion of nitric oxide (FeNO), number of unscheduled medical visits, and lost days of work/activity. Respiratory adverse events were assessed during the BT treatment period and at each post-BT visit.

RESULTS

Twenty-nine subjects completed the study; the median interquartile range (IQR) age was 47 (42-61), and the majority were female (69%), white (93%), and non-Hispanic (90%). After BT, mean (±std) AQLQ scores improved by 1.6(±1.1) at 3 months (p < 0.0001), 1.6(±1.2) at 6 months (p < 0.0001), 1.4(±1.0) at 12 months (p < 0.0001), 1.8(±1.1) at 18 months (p < 0.0001), and 1.6 (±1.5) at 24 months (p < 0.0001). There were significant improvements in ACT, PEFR, unscheduled medical visits and lost days of work and activity. Spirometry and FeNO metrics were unchanged. The average cost for subjects completing all 3 BT procedures was approximately $15,000.

CONCLUSION

BT is an effective adjunctive therapeutic modality in subjects with uncontrolled severe persistent asthma.

Pretreatment asthma control test score as a predictive score for clinical remission after bronchial thermoplasty in younger patients with severe asthma and preserved lung function

OBJECTIVE

Bronchial thermoplasty (BT) decreases the incidence of asthma exacerbations, emergency room visits, and hospitalizations among patients with severe asthma. Predictors of BT effectiveness remain unclear as its mechanism of action and invasiveness remain obscure. This study aimed to identify factors that could predict BT outcomes.

METHODS

Two respiratory physicians treated 20 consecutive patients with severe asthma using BT. The patients were assigned to groups based on clinical remission following an expert consensus proposed in 2020. Predictors of clinical remission were analyzed using asthma control test (ACT) score, pulmonary function and blood tests, and fractional exhaled nitric oxide.

RESULTS

At baseline, the median age was 44 years (interquartile range [IQR], 31.0-52.8), and pre-bronchodilator (pre-BD) percent predicted forced expiratory volume in one second (%FEV1) was 85.9% (IQR, 74.8-100.5). Six (30%) patients achieved clinical remission. Among the patients treated with biologics, 20% had clinical remission, and 20% discontinued biologic therapy. The pre-BT ACT score was significantly lower in the group with than without remission (11.0 [IQR, 8.0-14.5] vs. 15.0 [IQR, 11.0-17.3], p = .016). Adverse events did not significantly differ between the groups.

CONCLUSIONS

To the best of our knowledge, this is the first study to use clinical remission as a criterion for evaluating BT efficacy. The pre-BT ACT score might a the predict response to BT in younger adult patients with severe asthma and pre-BD %FEV1 ≥ 70%.

Exhaled breath analyses for bronchial thermoplasty in severe asthma patients

BACKGROUND

Bronchial thermoplasty (BT) is a bronchoscopic treatment for severe asthma. Although multiple trials have demonstrated clinical improvement after BT, optimal patient selection remains a challenge and the mechanism of action is incompletely understood. The aim of this study was to examine whether exhaled breath analysis can contribute to discriminate between BT-responders and non-responders at baseline and to explore pathophysiological insights of BT.

METHODS

Exhaled breath was collected from patients at baseline and six months post-BT. Patients were defined as responders or non-responders based on a half point increase in asthma quality of life questionnaire scores. Gas chromatography-mass spectrometry was used for volatile organic compounds (VOCs) detection and analyses. Analytical workflow consisted of: 1) detection of VOCs that differentiate between responders and non-responders and those that differ between baseline and six months post-BT, 2) identification of VOCs of interest and 3) explore correlations between clinical biomarkers and VOCs.

RESULTS

Data was available from 14 patients. Nonanal, 2-ethylhexanol and 3-thujol showed a significant difference in intensity between responders and non-responders at baseline (p = 0.04, p = 0.01 and p = 0.03, respectively). After BT, no difference was found in the compound intensity of these VOCs. A negative correlation was observed between nonanal and IgE and BALF eosinophils (r = -0.68, p < 0.01 and r = -0.61, p = 0.02 respectively) and 3-thujol with BALF neutrophils (r = -0.54, p = 0.04).

CONCLUSIONS

This explorative study identified discriminative VOCs in exhaled breath between BT responders and non-responders at baseline. Additionally, correlations were found between VOC's and inflammatory BALF cells. Once validated, these findings encourage research in breath analysis as a non-invasive easy to apply technique for identifying airway inflammatory profiles and eligibility for BT or immunotherapies in severe asthma.

Use of Quantitative CT Imaging to Identify Bronchial Thermoplasty Responders

BACKGROUND

Bronchial thermoplasty (BT) is a treatment for patients with poorly controlled, severe asthma. However, predictors of treatment response to BT are defined poorly.

RESEARCH QUESTION

Do baseline radiographic and clinical characteristics exist that predict response to BT?

STUDY DESIGN AND METHODS

We conducted a longitudinal prospective cohort study of participants with severe asthma receiving BT across eight academic medical centers. Participants received three separate BT treatments and were monitored at 3-month intervals for 1 year after BT. Similar to prior studies, a positive response to BT was defined as either improvement in Asthma Control Test results of ≥ 3 or Asthma Quality of Life Questionnaire of ≥ 0.5. Regression analyses were used to evaluate the association between pretreatment clinical and quantitative CT scan measures with subsequent BT response.

RESULTS

From 2006 through 2017, 88 participants received BT, with 70 participants (79.5%) identified as responders by Asthma Control Test or Asthma Quality of Life Questionnaire criteria. Responders were less likely to undergo an asthma-related ICU admission in the prior year (3% vs 25%; P = .01). On baseline quantitative CT imaging, BT responders showed less air trapping percentage (OR, 0.90; 95% CI, 0.82-0.99; P = .03), a greater Jacobian determinant (OR, 1.49; 95% CI, 1.05-2.11), greater SD of the Jacobian determinant (OR, 1.84; 95% CI, 1.04-3.26), and greater anisotropic deformation index (OR, 3.06; 95% CI, 1.06-8.86).

INTERPRETATION

To our knowledge, this is the largest study to evaluate baseline quantitative CT imaging and clinical characteristics associated with BT response. Our results show that preservation of normal lung expansion, indicated by less air trapping, a greater magnitude of isotropic expansion, and greater within-lung spatial variation on quantitative CT imaging, were predictors of future BT response.

TRIAL REGISTRY

ClinicalTrials.gov; No.: NCT01185275; URL: www.

CLINICALTRIALS

gov.

The airway epithelium: an orchestrator of inflammation, a key structural barrier and a therapeutic target in severe asthma

Asthma is a disease of heterogeneous pathology, typically characterised by excessive inflammatory and bronchoconstrictor responses to the environment. The clinical expression of the disease is a consequence of the interaction between environmental factors and host factors over time, including genetic susceptibility, immune dysregulation and airway remodelling. As a critical interface between the host and the environment, the airway epithelium plays an important role in maintaining homeostasis in the face of environmental challenges. Disruption of epithelial integrity is a key factor contributing to multiple processes underlying asthma pathology. In this review, we first discuss the unmet need in asthma management and provide an overview of the structure and function of the airway epithelium. We then focus on key pathophysiological changes that occur in the airway epithelium, including epithelial barrier disruption, immune hyperreactivity, remodelling, mucus hypersecretion and mucus plugging, highlighting how these processes manifest clinically and how they might be targeted by current and novel therapeutics.

Airway smooth muscle and long-term clinical efficacy following bronchial thermoplasty in severe asthma

The mechanism of action of bronchial thermoplasty (BT) treatment for patients with severe asthma is incompletely understood. This study investigated the 2.5-year impact of BT on airway smooth muscle (ASM) mass and clinical parameters by paired data analysis in 22 patients. Our findings demonstrate the persistence of ASM mass reduction of >50% after 2.5 years. Furthermore, sustained improvement in asthma control, quality of life and exacerbation rates was found, which is in line with previous reports. An association was found between the remaining ASM and both the exacerbation rate (r=0.61, p=0.04 for desmin, r=0.85, p<0.01 for alpha smooth muscle actin (SMA)) and post-bronchodilator forced expiratory volume in 1 s predicted percentage (r=-0.69, p=0.03 for desmin, r=-0.58, p=0.08 for alpha SMA). This study provides new insight into the long-term impact of BT.

Airway wall extracellular matrix changes induced by bronchial thermoplasty in severe asthma

BACKGROUND

Airway remodeling is a prominent feature of asthma, which involves increased airway smooth muscle mass and altered extracellular matrix composition. Bronchial thermoplasty (BT), a bronchoscopic treatment for severe asthma, targets airway remodeling.

OBJECTIVE

We sought to investigate the effect of BT on extracellular matrix composition and its association with clinical outcomes.

METHODS

This is a substudy of the TASMA trial. Thirty patients with severe asthma were BT-treated, of whom 13 patients were treated for 6 months with standard therapy (control group) before BT. Demographic data, clinical data including pulmonary function, and bronchial biopsies were collected. Biopsies at BT-treated and nontreated locations were analyzed by histological and immunohistochemical staining. Associations between histology and clinical outcomes were explored.

RESULTS

Six months after treatment, it was found that the reticular basement membrane thickness was reduced from 7.28 μm to 5.74 μm (21% relative reduction) and the percentage area of tissue positive for collagen increased from 26.3% to 29.8% (13% relative increase). Collagen structure analysis revealed a reduction in the curvature frequency of fibers. The percentage area positive for fibulin-1 and fibronectin increased by 2.5% and 5.9%, respectively (relative increase of 124% and 15%). No changes were found for elastin. The changes in collagen and fibulin-1 negatively associated with changes in FEV1 reversibility.

CONCLUSIONS

Besides reduction of airway smooth muscle mass, BT has an impact on reticular basement membrane thickness and the extracellular matrix arrangement characterized by an increase in tissue area occupied by collagen with a less dense fiber organization. Both collagen and fibulin-1 are negatively associated with the change in FEV1 reversibility.

Bronchial thermoplasty attenuates bronchodilator responsiveness

INTRODUCTION

Bronchial thermoplasty is an effective intervention to improve respiratory symptoms and to reduce the rate of exacerbations in uncontrolled severe asthma. A reduction in airway smooth muscle is arguably the most widely discussed mechanisms accounting for these clinical benefits. Yet, this smooth muscle reduction should also translate into an impaired response to bronchodilator drugs. This study was designed to address this question.

METHODS

Eight patients with clinical indication for thermoplasty were studied. They were uncontrolled severe asthmatics despite optimal environmental control, treatment of comorbidities, and the use of high-dose inhaled corticosteroids and long-acting β2-agonists. Lung function measured by spirometry and respiratory mechanics measured by oscillometry were examined pre- and post-bronchodilator (salbutamol, 400 μg), both before and at least 1 year after thermoplasty.

RESULTS

Consistent with previous studies, thermoplasty yielded no benefits in terms of baseline lung function and respiratory mechanics, despite improving symptoms based on two asthma questionnaires (ACQ-5 and ACT-5). The response to salbutamol was also not affected by thermoplasty based on spirometric readouts, including forced expiratory volume in 1 s (FEV1), forced vital capacity (FVC), and FEV1/FVC ratio. However, a significant interaction was observed between thermoplasty and salbutamol for two oscillometric readouts, namely reactance at 5 Hz (Xrs5) and reactance area (Ax), showing an attenuated response to salbutamol after thermoplasty.

CONCLUSIONS

Thermoplasty attenuates the response to a bronchodilator. We argue that this result is a physiological proof of therapeutic efficacy, consistent with the well-described effect of thermoplasty in reducing the amount of airway smooth muscle.

An underlying mechanism behind interventional pulmonology techniques for refractory asthma treatment: Neuro-immunity crosstalk

Asthma is a common disease that seriously threatens public health. With significant developments in bronchoscopy, different interventional pulmonology techniques for refractory asthma treatment have been developed. These technologies achieve therapeutic purposes by targeting diverse aspects of asthma pathophysiology. However, even though these newer techniques have shown appreciable clinical effects, their differences in mechanisms and mutual commonalities still deserve to be carefully explored. Therefore, in this review, we summarized the potential mechanisms of bronchial thermoplasty, targeted lung denervation, and cryoablation, and analyzed the relationship between these different methods. Based on available evidence, we speculated that the main pathway of chronic airway inflammation and other pathophysiologic processes in asthma is sensory nerve-related neurotransmitter release that forms a "neuro-immunity crosstalk" and amplifies airway neurogenic inflammation. The mechanism of completely blocking neuro-immunity crosstalk through dual-ablation of both efferent and afferent fibers may have a leading role in the clinical efficacy of interventional pulmonology in the treatment of asthma and deserves further investigation.

GEMA 5.3. Spanish Guideline on the Management of Asthma

The Spanish Guideline on the Management of Asthma, better known by its acronym in Spanish GEMA, has been available for more than 20 years. Twenty-one scientific societies or related groups both from Spain and internationally have participated in the preparation and development of the updated edition of GEMA, which in fact has been currently positioned as the reference guide on asthma in the Spanish language worldwide. Its objective is to prevent and improve the clinical situation of people with asthma by increasing the knowledge of healthcare professionals involved in their care. Its purpose is to convert scientific evidence into simple and easy-to-follow practical recommendations. Therefore, it is not a monograph that brings together all the scientific knowledge about the disease, but rather a brief document with the essentials, designed to be applied quickly in routine clinical practice. The guidelines are necessarily multidisciplinary, developed to be useful and an indispensable tool for physicians of different specialties, as well as nurses and pharmacists. Probably the most outstanding aspects of the guide are the recommendations to: establish the diagnosis of asthma using a sequential algorithm based on objective diagnostic tests; the follow-up of patients, preferably based on the strategy of achieving and maintaining control of the disease; treatment according to the level of severity of asthma, using six steps from least to greatest need of pharmaceutical drugs, and the treatment algorithm for the indication of biologics in patients with severe uncontrolled asthma based on phenotypes. And now, in addition to that, there is a novelty for easy use and follow-up through a computer application based on the chatbot-type conversational artificial intelligence (ia-GEMA).

Reduced Asthma Exacerbations in Adult Patients Treated With Bronchial Thermoplasty

BACKGROUND

Bronchial thermoplasty (BT) has been shown to be effective in randomized controlled trials of patients with severe asthma who failed to achieve disease control with high-dose inhaled corticosteroids combined with bronchodilators. However, the effectiveness of BT in real-world clinical settings, especially among the Asian population, has not been determined.

OBJECTIVE

To evaluate the effectiveness of BT using a nationwide database.

METHODS

Using the inpatient and outpatient data from the Japanese Diagnosis Procedure Combination database, we applied a self-controlled case series design to evaluate changes in the composite outcome of hospital admissions and emergency department visits, as well as systemic corticosteroid dose, between 1 year before and after BT. We also conducted subgroup analyses based on patients' profiles.

RESULTS

Among the 561 patients with asthma who underwent BT treatment between September 2014 and March 2020, 102 patients with at least 1 outcome were analyzed. Bronchial thermoplasty was significantly associated with an improvement in the composite outcome of hospital admission and emergency department visits (incidence rate ratio 0.53; 95% CI 0.44-0.64). Systemic corticosteroid use was reduced after BT sessions (1931.5 mg [1,341.2-3,725.3 mg] to 641.3 mg [134.2-1,691.1 mg] per person-year; P < .001). Although all groups showed a significant improvement in the composite outcome in the subgroup analyses, BT tended to be less effective among people older than 65 years and those with higher body mass index (>25 kg/m2).

CONCLUSIONS

The present study using real-world data suggests that BT may improve asthma control; however, the effectiveness of BT can vary depending on patient baseline profiles.

In vivo polarisation sensitive optical coherence tomography for fibrosis assessment in interstitial lung disease: a prospective, exploratory, observational study

INTRODUCTION

Endobronchial polarisation sensitive optical coherence tomography (EB-PS-OCT) is a bronchoscopic imaging technique exceeding resolution of high-resolution CT (HRCT) by 50-fold. It detects collagen birefringence, enabling identification and quantification of fibrosis.

STUDY AIM

To assess pulmonary fibrosis in interstitial lung diseases (ILD) patients with in vivo EB-PS-OCT using histology as reference standard.

PRIMARY OBJECTIVE

Visualisation and quantification of pulmonary fibrosis by EB-PS-OCT.

SECONDARY OBJECTIVES

Comparison of EB-PS-OCT and HRCT detected fibrosis with histology, identification of ILD histological features in EB-PS-OCT images and comparison of ex vivo PS-OCT results with histology.

METHODS

Observational prospective exploratory study. Patients with ILD scheduled for transbronchial cryobiopsy or surgical lung biopsy underwent in vivo EB-PS-OCT imaging prior to tissue acquisition. Asthma patients were included as non-fibrotic controls. Per imaged lung segment, fibrosis was automatically quantified assessing the birefringent area in EB-PS-OCT images. Fibrotic extent in corresponding HRCT areas and biopsies were compared with EB-PS-OCT detected fibrosis. Microscopic ILD features were identified on EB-PS-OCT images and matched with biopsies from the same segment.

RESULTS

19 patients were included (16 ILD; 3 asthma). In 49 in vivo imaged airway segments the parenchymal birefringent area was successfully quantified and ranged from 2.54% (no to minimal fibrosis) to 21.01% (extensive fibrosis). Increased EB-PS-OCT detected birefringent area corresponded to increased histologically confirmed fibrosis, with better predictive value than HRCT. Microscopic ILD features were identified on both in vivo and ex vivo PS-OCT images.

CONCLUSIONS

EB-PS-OCT enables pulmonary fibrosis quantification, thereby has potential to serve as an add-on bronchoscopic imaging technique to diagnose and detect (early) fibrosis in ILD.

Effect of budesonide combined with montelukast sodium on pulmonary function parameters and immunoglobulin levels in children with bronchial asthma

BACKGROUND AND AIM

Bronchial asthma is a prevalent type of respiratory disease that affects a large proportion of pediatric patients. The purpose of this study is to further investigate the clinical effects of budesonide combined with montelukast sodium in treating bronchial asthma.

METHODS

Eighty six children with bronchial asthma were equally divided into study and control groups via randomized double-blind controlled trial. The control group was treated with aerosol inhalation of budesonide combined with placebo, while the study group was treated with budesonide combined with montelukast sodium. Pulmonary function parameters, immunoglobulin, and recovery of related symptoms, along with the adverse reaction rate, were observed and compared between both groups.

RESULTS

Before treatment, there was no marked difference in pulmonary function parameters and immunoglobulin indexes between both groups (P > 0.05). All pulmonary function indicators and immunoglobulin indexes in both groups improved following therapy, with the study group outperforming the control group (P < 0.05). The recovery time of related symptoms in the study group was shorter than that in the control group (P < 0.05). The incidence of adverse reactions in both groups was compared, with notable differences (P < 0.05).

CONCLUSION

Budesonide combined with montelukast sodium in the treatment of bronchial asthma has the value of clinical application and promotion.

The reduction of airway smooth muscle by bronchial thermoplasty stands the test of time

Airway smooth muscle ablation induced by thermoplasty is maintained for >10 years along with the improvements in asthma control https://bit.ly/3nGqQSP.

Bronchial thermoplasty improves cough hypersensitivity and cough in severe asthmatics

BACKGROUND

Cough is a troublesome symptom of asthma because it is associated with disease severity and poor asthma control. Bronchial thermoplasty (BT) may be effective in improving cough severity and cough-related quality of life in severe uncontrolled asthma.

OBJECTIVE

To evaluate the efficacy of BT for cough in severe uncontrolled asthma.

METHODS

Twelve patients with severe uncontrolled asthma were enrolled in this study between 2018 May and March 2021 and arbitrarily divided into cough-predominant [cough severity Visual Analog Scale (VAS) ≥ 40 mm, n = 8] and typical asthma (cough VAS <40 mm, n = 4) groups. Clinical parameters, such as capsaicin cough sensitivity [C-CS: the concentrations to inhaled capsaicin required to induce at least two (C2) and five (C5) coughs], lung function, and type-2-related biomarkers (fractional nitric oxides and absolute eosinophil counts) and cough-related indices [cough severity VAS and the Leicester Cough Questionnaire (LCQ)] were evaluated before and 3 months after performing BT.

RESULTS

BT significantly improved both cough-related indices and C-CS in the cough-predominant group. Changes in C-CS were significantly correlated with changes in the LCQ scores (C5: r = 0.65, p = 0.02 for all patients, and r = 0.81, p = 0.01 for the cough-predominant group).

CONCLUSIONS

BT may be effective for cough in severe uncontrolled asthma by improving C-CS. However, further larger cohort studies are necessary to confirm the effect of BT for cough in asthma.

CLINICAL TRIAL REGISTRATION

This study was registered in the UMIN Clinical Trials Registry (Registry ID UMIN: 000031982).

Endobronchial Ultrasound is Useful in the Assessment of Bronchial Wall Changes Related to Bronchial Thermoplasty

Background

Bronchial thermoplasty (BT) is an interventional endoscopic treatment for severe asthma leading to the clinical improvement, but morphologic changes of bronchial wall related to the procedure and predictors of a favorable response to BT remain uncertain. The aim of the study was to validate an endobronchial ultrasound (EBUS) in assessing the effectiveness of BT treatment.

Methods

Patients with severe asthma who met the clinical criteria for BT were included. In all patients clinical data, ACT and AQLQ questionnaires, laboratory tests, pulmonary function tests and bronchoscopy with radial probe EBUS and bronchial biopsies were collected. BT was performed in patients with the thickest bronchial wall L₂ layer representing ASM. These patients were evaluated before and after 12 months of follow-up. The relationship between baseline parameters and clinical response was explored.

Results

Forty patients with severe asthma were enrolled to the study. All 11 patients qualified to BT successfully completed the 3 sessions of bronchoscopy. BT improved asthma control (P=0.006), quality of life (P=0.028) and decreased exacerbation rate (P=0.005). Eight of the 11 patients (72.7%) showed a clinically meaningful improvement. BT also led to a significant decrease in the thicknesses of bronchial wall layers in EBUS (L₁ decreased from 0.183 to 0.173 mm, P=0.003; L₂ from 0.207 to 0.185 mm, P = 0.003; and L_3-5 from 0.969 to 0.886 mm, P=0.003). Median ASM mass decreased by 61.8% (P=0.002). However, there was no association between baseline patient characteristics and the magnitude of clinical improvement after BT.

Conclusion

BT was associated with a significant decrease in the thickness of the bronchial wall layers measured by EBUS including L₂ layer representing ASM and ASM mass reduction in bronchial biopsy. EBUS can assess bronchial structural changes related to BT; however, it did not predict the favorable clinical response to therapy.

Comparing bronchial thermoplasty with biologicals for severe asthma: Systematic review and network meta-analysis

BACKGROUND

Bronchial thermoplasty (BT) has shown favorable safety and efficacy in several randomized controlled trials (RCTs), but has not been directly compared to biological therapies.

METHODS

Electronic literature searches were performed on PubMed, EMBASE, and the Cochrane Central Register of Controlled Trials, to retrieve RCTs of BT or FDA-approved biologicals against controls in patients with severe asthma. Six outcomes were analyzed: Asthma Control Questionnaire (ACQ), Asthma Quality of Life Questionnaire (AQLQ), the number of patients experiencing ≥1 asthma exacerbation, annualized exacerbation rate ratio (AERR), oral corticosteroid dose reduction (OCDR), and morning peak expiratory flow rate (amPEF). Random-effects, Frequentist network meta-analysis (NMA) were performed, and therapies were ranked using P-scores.

RESULTS

Twenty-nine RCTs (15,547 patients) were included. Fewer patients treated with BT experienced ≥1 asthma exacerbation (risk ratio [RR] = 0.66, 95%CI = 0.45-0.98) compared to control. AERR of BT versus control was non-significant, but significant improvements in ACQ score (mean difference [MD] -0.41, 95%CI -0.63 to -0.20), AQLQ score (MD = 0.54, 95%CI = 0.30-0.77), amPEF and OCDR were found. No significant differences between BT and biologics were seen across indirect comparisons of all studies.

CONCLUSIONS

Despite the lack of head-to-head comparative trials, this NMA suggests that BT is non-inferior to biologicals in terms of quality-of-life scores, and represents a promising alternative for patients with severe asthma.

A prognosis prediction chromatin regulator signature for patients with severe asthma

Severe asthma imposes a physical and economic burden on both patients and society. As chromatin regulators (CRs) influence the progression of multiple diseases through epigenetic mechanisms, we aimed to study the role of CRs in patients with severe asthma. Transcriptome data (GSE143303) from 47 patients with severe asthma and 13 healthy participants was downloaded from the Gene Expression Omnibus database. Enrichment analysis was performed to investigate the functions of differentially expressed CRs between the groups. We identified 80 differentially expressed CRs; they were mainly enriched in histone modification, chromatin organization, and lysine degradation. A protein-protein interaction network was then constructed. The analyzed immune scores were different between sick and healthy individuals. Thus, CRs with a high correlation in the immune analysis, SMARCC1, SETD2, KMT2B, and CHD8, were used to construct a nomogram model. Finally, using online prediction tools, we determined that lanatoside C, cefepime, and methapyrilene may be potentially effective drugs in the treatment of severe asthma. The nomogram constructed using the four CRs, SMARCC1, SETD2, KMT2B, and CHD8, may be a useful tool for predicting the prognosis of patients with severe asthma. This study provided new insights into the role of CRs in severe asthma.

Executive summary: Japanese guidelines for adult asthma (JGL) 2021

Asthma is characterized by chronic airway inflammation, variable airway narrowing, and sensory nerve irritation, which manifest as wheezing, dyspnea, chest tightness, and cough. Longstanding asthma may result in airway remodeling and become intractable. Despite the increased prevalence of asthma in adults, asthma-associated deaths have decreased in Japan (0.94 per 100,000 people in 2020). The goals of asthma treatment include the control of symptoms and reduction of future risks. A functional partnership between physicians and patients is indispensable for achieving these goals. Long-term management with medications and the elimination of triggers and risk factors are fundamental to asthma treatment. Asthma is managed via four steps of pharmacotherapy ("controllers"), ranging from mild to intensive treatments, depending on disease severity; each step involves daily administration of an inhaled corticosteroid, which varies from low to high dosage. Long-acting β₂ agonists, leukotriene receptor antagonists, sustained-release theophylline, and long-acting muscarinic antagonists are recommended as add-on drugs. Allergen immunotherapy is a new option that is employed as a controller treatment. Further, as of 2021, anti-IgE antibody, anti-IL-5 and anti-IL-5 receptor α-chain antibodies, and anti-IL-4 receptor α-chain antibodies are available for the treatment of severe asthma. Bronchial thermoplasty can be performed for asthma treatment, and its long-term efficacy has been reported. Algorithms for their usage have been revised. Comorbidities, such as allergic rhinitis, chronic rhinosinusitis, chronic obstructive pulmonary disease, and aspirin-exacerbated respiratory disease, should also be considered during the treatment of chronic asthma. Depending on the severity of episodes, inhaled short-acting β₂ agonists, systemic corticosteroids, short-acting muscarinic antagonists, oxygen therapy, and other approaches are used as needed ("relievers") during exacerbation.

Development of Adaptive Immunity and Its Role in Lung Remodeling

Asthma is characterized by airflow limitations resulting from bronchial closure, which can be either reversible or fixed due to changes in airway tissue composition and structure, also known as remodeling. Airway remodeling is defined as increased presence of mucins-producing epithelial cells, increased thickness of airway smooth muscle cells, angiogenesis, increased number and activation state of fibroblasts, and extracellular matrix (ECM) deposition. Airway inflammation is believed to be the main cause of the development of airway remodeling in asthma. In this chapter, we will review the development of the adaptive immune response and the impact of its mediators and cells on the elements defining airway remodeling in asthma.

Bronchial thermoplasty for the treatment of severe persistent asthma

PURPOSE OF REVIEW

Severe asthma is associated with frequent hospital visits and impact in quality of life as well as healthcare associated costs. Limited treatment modalities exist to assist in reduction of frequent exacerbations in patients with severe asthma who are already on maximum inhaler therapy. As supporting data becomes more robust, novel treatments have gained attention such as bronchial thermoplasty and immune-directed therapies.

RECENT FINDINGS

Based on review of recent studies, bronchial thermoplasty poses itself as a potential intervention for severe asthma, demonstrating a decrease in asthma exacerbations with long term clinical effect and safety profile at the expense of temporary uncontrolled asthma symptoms for the first six weeks following the procedure.

SUMMARY

In select patients with severe asthma, bronchial thermoplasty is a well tolerated and effective treatment to reduce asthma exacerbation.

Which Endoscopic Procedure to Use and in What Patient? Valves, Coils, Foam, and Heat in COPD and Asthma

Despite the latest developments in therapeutic agents targeting airway endotypes, a significant proportion of patients with asthma and chronic obstructive pulmonary disease (COPD) remain symptomatic. Endoscopic therapies have a complementary role in the management of these airway diseases. The sustained efficacy of bronchial thermoplasty (BT) among patients with asthma over 10 years has been encouraging, as it has been shown to improve symptom control and reduce hospital admissions and exacerbations. Studies suggest that BT helps ameliorate airway inflammation and reduce airway smooth muscle thickness. While studies suggest that it is as effective as biologic agents, its role in the management of severe asthma has yet to be clearly defined and GINA 2022 still suggests limiting its use to patients with characteristics of the various populations studied. Conversely, bronchoscopic lung volume reduction has shown promise among patients with advanced COPD. Rigorous patient selection is important. Patients with minimal collateral ventilation (CV) and higher heterogeneity index have shown to benefit the most from endobronchial valve (EBV) therapy. For those with ongoing CV, endobronchial coils would be more appropriate. Both therapeutic modalities have demonstrated improved quality of life, effort tolerance, and lung function indices among appropriately selected patients. The emerging evidence suggests that endoscopic procedures among airway disease still have a substantial role to play despite the development of new therapeutic options.

Airway Inflammation Before and After Bronchial Thermoplasty in Severe Asthma

Background

Bronchial thermoplasty (BT) is a bronchoscopic treatment for severe asthma, of which the working mechanism and responder profile are partly unknown. The aim of this study is to analyse whether BT alters airway inflammation by epithelial gene expression, inflammatory cell counts and cytokines, and whether this relates to treatment response.

Methods

In this clinical trial, 28 severe asthma patients underwent bronchoscopy before and after treatment to obtain bronchial brushes and bronchoalveolar lavage fluid (BALF) from treated and untreated airways. RNA was extracted from bronchial brushes for transcriptome analysis, and BALF cells and cytokines were analysed. Asthma quality of life questionnaires were used to distinguish responders from non-responders. We compared results before and after treatment, between treated and untreated airways, and between responders and non-responders.

Results

Gene expression of airway epithelium related to airway inflammation gene set was significantly downregulated in treated airways compared to untreated airways, although this did not differ for patients before and after treatment. No differences were observed in cell counts and cytokines, neither from the untreated compared to treated airways, nor before and after treatment. At baseline, compared to non-responders, the expression of genes related to glycolysis in bronchial epithelium was downregulated and both BALF and blood eosinophil counts were higher in responders.

Conclusion

Local differences in gene sets pertaining to epithelial inflammatory status were identified between treated and untreated airways after treatment, not resulting in changes in differential cell counts and cytokine analyses in BALF. Secondly, baseline epithelial glycolysis genes and eosinophil counts in BALF and blood were different between responders and non-responders. The observations from this study demonstrate the potential impact of BT on epithelial gene expression related to airway inflammation while also identifying a possible responder profile.

Advances in Evaluation and Treatment of Severe Asthma (Part Two)

Providers caring for patients with severe, therapy-resistant asthma have novel options for their treatment. Administration of additional inhaled corticosteroids at the time of increased symptoms, a strategy referred to as anti-inflammatory rescue or AIR, has been proved to be effective in reducing the frequency of exacerbations and improving asthma-related quality of life. Long-acting muscarinic antagonists can be used in combination with long-acting beta-agonist bronchodilators for additional bronchodilation. The care of the patient with severe asthma must also include a strategy to help avoid severe, life-threatening asthma attacks, with intense patient education and a recommended survival toolkit.

[Markers of severity and predictors of response to treatment in severe asthma]

Asthma is a multifactorial disease with complex pathophysiology. Knowledge of its immunopathology and inflammatory mechanisms is progressing and has led to the development over recent years of increasingly targeted therapeutic strategies. The objective of this review is to pinpoint the different predictive markers of asthma severity and therapeutic response. Obesity, nasal polyposis, gastroesophageal reflux disease and intolerance to aspirin have all been considered as clinical markers associated with asthma severity, as have functional markers such as bronchial obstruction, low FEV1, small daily variations in FEV1, and high FeNO. While sinonasal polyposis and allergic comorbidities are associated with better response to omalizumab, nasal polyposis or long-term systemic steroid use are associated with better response to antibodies targeting the IL5 pathway. Elevated total IgE concentrations and eosinophil counts are classic biological markers regularly found in severe asthma. Blood eosinophils are predictive biomarkers of response to anti-IgE, anti-IL5, anti-IL5R and anti-IL4R biotherapies. Dupilumab is particularly effective in a subgroup of patients with marked type 2 inflammation (long-term systemic corticosteroid therapy, eosinophilia≥150/μl or FENO>20 ppb). Chest imaging may help to identify severe patients by seeking out bronchial wall thickening and bronchial dilation. Study of the patient's environment is crucial insofar as exposure to tobacco, dust mites and molds, as well as outdoor and indoor air pollutants (cleaning products), can trigger asthma exacerbation. Wider and more systematic use of markers of severity or response to treatment could foster increasingly targeted and tailored approaches to severe asthma.

Bronchial smooth muscle cell in asthma: where does it fit?

Asthma is a frequent respiratory condition whose pathophysiology relies on altered interactions between bronchial epithelium, smooth muscle cells (SMC) and immune responses. Those leads to classical hallmarks of asthma: airway hyper-responsiveness, bronchial remodelling and chronic inflammation. Airway smooth muscle biology and pathophysiological implication in asthma are now better understood. Precise deciphering of intracellular signalling pathways regulating smooth muscle contraction highlighted the critical roles played by small GTPases of Rho superfamily. Beyond contractile considerations, active involvement of airway smooth muscle in bronchial remodelling mechanisms is now established. Not only cytokines and growth factors, such as fibroblats growth factor or transforming growth factor-β, but also extracellular matrix composition have been demonstrated as potent phenotype modifiers for airway SMC. Although basic science knowledge has grown significantly, little of it has translated into improvement in asthma clinical practice. Evaluation of airway smooth muscle function is still limited to its contractile activity. Moreover, it relies on tools, such as spirometry, that give only an overall assessment and not a specific one. Interesting technics such as forced oscillometry or specific imagery (CT and MRI) give new perspectives to evaluate other aspects of airway muscle such as bronchial remodelling. Finally, except for the refinement of conventional bronchodilators, no new drug therapy directly targeting airway smooth muscle proved its efficacy. Bronchial thermoplasty is an innovative and efficient therapeutic strategy but is only restricted to a small proportion of severe asthmatic patients. New diagnostic and therapeutic strategies specifically oriented toward airway smooth muscle are needed to improve global asthma care.

Documento de consenso de asma grave en adultos. Actualización 2022

Severe asthma is a heterogeneous syndrome with several clinical variants and often represents a complex disease requiring a specialized and multidisciplinary approach, as well as the use of multiple drugs. The prevalence of severe asthma varies from one country to another, and it is estimated that 50% of these patients present a poor control of their disease. For the best management of the patient, it is necessary a correct diagnosis, an adequate follow-up and undoubtedly to offer the best available treatment, including biologic treatments with monoclonal antibodies. With this objective, this consensus process was born, which began in its first version in 2018, whose goal is to offer the patient the best possible management of their disease in order to minimize their symptomatology. For this 2020 consensus update, a literature review was conducted by the authors. Subsequently, through a two-round interactive Delphi process, a broad panel of asthma experts from SEPAR and the regional pulmonology societies proposed the recommendations and conclusions contained in this document.

Eosinophilic Asthma, Phenotypes-Endotypes and Current Biomarkers of Choice

Asthma phenotyping and endotyping are constantly evolving. Currently, several biologic agents have been developed towards a personalized approach to asthma management. This review will focus on different eosinophilic phenotypes and Th2-associated endotypes with eosinophilic inflammation. Additionally, airway remodeling is analyzed as a key feature of asthmatic eosinophilic endotypes. In addition, evidence of biomarkers is examined with a predictive value to identify patients with severe, uncontrolled asthma who may benefit from new treatment options. Finally, there will be a discussion on the results from clinical trials regarding severe eosinophilic asthma and how the inhibition of the eosinophilic pathway by targeted treatments has led to the reduction of recurrent exacerbations.

Bronchial thermoplasty: State of the art

Since the publication of a sham-controlled, randomized trial (AIR2) and subsequent marketing approval by the US Food and Drug Administration, we have significantly advanced our understanding of bronchial thermoplasty (BT)'s scientific basis, long-term safety, clinical efficacy and cost-effectiveness. In particular, the last 2 years have witnessed multiple research publications on several of these counts. In this review, we critically appraise our evolving understanding of BT's biologic underpinnings and clinical impact, offer an evidence-based patient workflow guide for the busy pulmonologist and highlight both current challenges as well as potential solutions for the researcher and the clinician.

Paucigranulocytic Asthma: Potential Pathogenetic Mechanisms, Clinical Features and Therapeutic Management

Asthma is a heterogeneous disease usually characterized by chronic airway inflammation, in which several phenotypes have been described, related to the age of onset, symptoms, inflammatory characteristics and treatment response. The identification of the inflammatory phenotype in asthma is very useful, since it allows for both the recognition of the asthmatic triggering factor as well as the optimization of treatment The paucigranulocytic phenotype of asthma (PGA) is characterized by sputum eosinophil levels <1−3% and sputum neutrophil levels < 60%. The precise characteristics and the pathobiology of PGA are not fully understood, and, in some cases, it seems to represent a previous eosinophilic phenotype with a good response to anti-inflammatory treatment. However, many patients with PGA remain uncontrolled and experience asthmatic symptoms and exacerbations, irrespective of the low grade of airway inflammation. This observation leads to the hypothesis that PGA might also be either a special phenotype driven by different kinds of cells, such as macrophages or mast cells, or a non-inflammatory phenotype with a low grade of eosinophilic inflammation. In this review, we aim to describe the special characteristics of PGA and the potential therapeutic interventions that could be offered to these patients.

ERS International Congress 2021: highlights from the Clinical Techniques, Imaging and Endoscopy Assembly

This article summarises the highlights from the European Respiratory Society's “Clinical techniques, imaging and endoscopy” Assembly 14 presented at the virtual 2021 European Respiratory Society International Congress. Cutting-edge innovative developments in both diagnostic approaches and therapeutic strategies in patients with lung cancer, interstitial lung disease, obstructive airway disorders and infectious diseases were presented on this year's interactive congress platform. In this article, the Assembly 14 subgroups summarise the key take home messages given new research outcomes and place them in the context of the current knowledge.

Correlation of Activation Site and Number with the Clinical Response to Bronchial Thermoplasty

Objective

Methods

Results

Conclusion

Plethysmography Derived Gas Trapping Lacks Utility in Predicting Response to Bronchial Thermoplasty

There is a paucity of literature on measurable baseline parameters predicting response and guiding selection for bronchial thermoplasty. This study examines whether baseline gas trapping, as assessed by plethysmography, is associated with a response to bronchial thermoplasty at 12 months.

43 consecutive patients with severe asthma (mean±sd age 57.6±13.3 years) were evaluated at baseline and 12 months post bronchial thermoplasty. Data collected at both time points included spirometry, body plethysmography and four clinical outcome measures, namely Asthma Control Questionnaire (ACQ) score, annual exacerbation frequency, maintenance oral corticosteroid requirement and short-acting β-agonist use.

At baseline, participants had severe airflow obstruction (forced expiratory volume in 1 s 49.1±15.8%) with marked gas trapping (residual volume (RV) 150.3±40.8%, RV/total lung capacity (TLC) 51.3±10.5%), poor symptom control (ACQ 3.3±1.0) and frequent exacerbations (median 4, interquartile range 8). 12 months after bronchial thermoplasty, significant improvements were observed in all four clinical outcome measures. However, baseline RV and RV/TLC were not significantly associated with changes in ACQ nor any other clinical outcome measure, and changes in RV and RV/TLC did not significantly correlate with a change in any clinical outcome measure.

Plethysmography-derived gas trapping does not demonstrate utility in predicting response and guiding selection for bronchial thermoplasty. An improvement in gas trapping was not associated with positive clinical outcomes, suggesting that this may not be the dominant mode of action of bronchial thermoplasty in generating clinical improvement.

This study examined whether measuring gas trapping by plethysmography could be used to predict response to bronchial thermoplasty; no association was foundhttps://bit.ly/3tJN1X8

Endobronchial treatment of severe asthma and severe emphysema with hyperinflation

PURPOSE OF REVIEW

The field of interventional pulmonology has ushered in a wave of innovations for individuals with obstructive airways disease in whom established medical therapies have failed. Leading the charge are bronchial thermoplasty for severe refractory asthma and uni-directional valves for severe emphysema with hyperinflation: both have received regulatory approvals in the United Kingdom and United States. With the commissioning of these novel treatments comes new challenges relating to implementation, positioning within therapeutic algorithms, honing of patient selection, and establishing long-term safety and benefits beyond 5 years.

RECENT FINDINGS

This review summarises the evidence for their safety and efficacy, predictors of therapeutic response, mechanism(s) of action and emerging data supporting the durability of outcomes out to at least ten years.

SUMMARY

It is anticipated the experience of treating increasing numbers of patients, the adoption of international registries, and ongoing research evaluations will serve to optimise these therapies for future generations of patients.

Long-term modulation of airway remodelling in severe asthma following bronchial thermoplasty

Rationale

Bronchial thermoplasty is a mechanical therapeutic intervention that has been advocated as an effective treatment option for severe asthma. The mechanism is promoted as being related to the attenuation of airway smooth muscle which has been shown to occur in the short-term. However, long-term studies of the effects of bronchial thermoplasty on airway remodelling are few, with only limited assessment of airway remodelling indices.

Objectives

To evaluate the effect of bronchial thermoplasty on 1) airway epithelial and smooth muscle cells in culture and 2) airway remodelling in patients with severe asthma who have been prescribed bronchial thermoplasty up to 12 months post-treatment.

Methods

The distribution of heat within the airway by bronchial thermoplasty was assessed in a porcine model. Culture of human airway smooth muscle cells and bronchial epithelial cells evaluated the impact of thermal injury. Histological evaluation and morphometric assessment were performed on bronchial biopsies obtained from severe asthma patients at baseline, 6 weeks and 12 months following bronchial thermoplasty.

Results

Bronchial thermoplasty resulted in heterogeneous heating of the airway wall. Airway smooth muscle cell cultures sustained thermal injury, whilst bronchial epithelial cells were relatively resistant to heat. Airway smooth muscle and neural bundles were significantly reduced at 6 weeks and 12 months post-treatment. At 6 weeks post-treatment, submucosal collagen was reduced and vessel density increased, with both indices returning to baseline at 12 months. Goblet cell numbers, submucosal gland area and sub-basement membrane thickness were not significantly altered at any time point examined.

Conclusions

Bronchial thermoplasty primarily affects airway smooth muscle and nerves with the effects still present at 12 months post-treatment.

Which Therapy for Non-Type(T)2/T2-Low Asthma

Currently, the asthmatic population is divided into Type 2-high and non-Type 2/Type 2-low asthmatics, with 50% of patients belonging to one of the two groups. Differently from T2-high, T2-low asthma has not been clearly defined yet, and the T2-low patients are identified on the basis of the absence or non-predominant expression of T2-high biomarkers. The information about the molecular mechanisms underpinning T2-low asthma is scarce, but researchers have recognized as T2-low endotypes type 1 and type 3 immune response, and remodeling events occurring without inflammatory processes. In addition, the lack of agreed biomarkers reprents a challenge for the research of an effective therapy. The first-choice medication is represented by inhaled corticosteroids despite a low efficacy is reported for/in T2-low patients. However, macrolides and long-acting anti-muscarinic drugs have been recognized as efficacious. In recent years, clinical trials targeting biomarkers playing key roles in T3 and T1 immune pathways, alarmins, and molecules involved in neutrophil recruitment have provided conflicting results probably misleading (or biased) in patients' selection. However, further studies are warranted to achieve a precise characterization of T2-low asthma with the aim of defining a tailored therapy for each single asthmatic patient.

Bronchial Thermoplasty in Severe Asthmatics At 5 Years: The PAS2 Study

BACKGROUND

Bronchial thermoplasty is a device-based treatment for subjects ≥18 years with severe asthma poorly controlled with inhaled corticosteroids and long-acting beta-agonists. The Post-FDA Approval Clinical Trial Evaluating Bronchial Thermoplasty in Severe Persistent Asthma (PAS2) study collected data on severe asthmatics undergoing this procedure.

RESEARCH QUESTION

What are the 5-year efficacy and safety results in severe asthmatics who have undergone bronchial thermoplasty?

STUDY DESIGN AND METHODS

This was a prospective, open-label, observational, multi-center study conducted in the United States and Canada. Subjects aged 18-65, taking inhaled corticosteroids ≥1000μg/day (beclomethasone or equivalent) and long-acting β-agonists ≥80μg/day (salmeterol or equivalent) were included. Severe exacerbations, hospitalization, emergency department visits, and medication usage were evaluated for the 12 months prior to and at years 1-5 post-treatment. Spirometry was evaluated at baseline and at years 1-5 post-treatment.

RESULTS

284 subjects were enrolled at 27 centers; 227 subjects (80%) completed 5 years of follow-up. By year 5 post-treatment, the proportion of subjects with severe exacerbations, emergency department visits, and hospitalizations was 42.7%, 7.9%, and 4.8%, respectively, compared to 77.8%, 29.4%, and 16.1% in the 12 months prior to treatment. The proportion of subjects on maintenance oral corticosteroids decreased from 19.4% at baseline to 9.7% at 5 years. Analyses of subgroups based on baseline clinical and biomarker characteristics revealed a statistically significant clinical improvement among all subgroups.

INTERPRETATION

Five years after treatment, subjects experienced decreases in severe exacerbations, hospitalizations, emergency department visits and corticosteroid exposure. All subgroups demonstrated clinically significant improvement, suggesting that bronchial thermoplasty improves asthma control in different asthma phenotypes.

Bronchial thermoplasty guided by hyperpolarised gas magnetic resonance imaging in adults with severe asthma: a 1-year pilot randomised trial

Patient-specific localisation of ventilation defects using hyperpolarised gas magnetic resonance imaging (MRI) introduces the possibility of regionally targeted bronchial thermoplasty (BT) for the treatment of severe asthma. We aimed to demonstrate that BT guided by MRI to ventilation defects reduces the number of radiofrequency activations while resulting in improved asthma quality-of-life and control scores that are non-inferior to standard BT. In a 1-year pilot randomised controlled trial, 14 patients with severe asthma who were clinically eligible to receive BT underwent hyperpolarised gas MRI to characterise ventilation defects and were randomised to MRI-guided or standard BT. End-points were improved Asthma Quality of Life Questionnaire (AQLQ) and Asthma Control Questionnaire (ACQ) scores, the proportion of AQLQ and ACQ responders and the number of radiofrequency activations and bronchoscopy sessions. Participants who underwent MRI-guided BT received 53% fewer radiofrequency activations than those who had standard BT (p=0.003). At 12 months, the mean improvement from baseline was similar between the MRI-guided group (n=5) and the standard group (n=7) for AQLQ score (MRI-guided: 1.8, 95% CI 0.1-3.5, p=0.04; standard: 0.7, 95% CI -0.9-2.3, p=0.30) (p=0.25) and ACQ-5 score (MRI-guided: -1.4, 95% CI -2.6- -0.2, p=0.03; standard: -0.7, 95% CI -1.3-0.0, p=0.04) (p=0.17). A similar proportion of participants in both groups achieved a clinically relevant improvement in AQLQ score (MRI-guided: 80%; standard: 71%) and ACQ-5 score (MRI-guided: 80%; standard: 57%). Hyperpolarised gas MRI-guided BT reduced the number of radiofrequency activations, and resulted in asthma quality of life and control improvements at 12 months that were non-inferior to standard BT.

Use of Health Related Quality of Life in Clinical Trials for Severe Asthma: A Systematic Review

BACKGROUND

Asthma Health Related Quality of Life (HRQoL) is an outcome important to patients with severe asthma and can provide clinicians with additional insight into the benefits of treatment. The aim of this systematic review is to examine the use and reporting of HRQoL questionnaires within randomised controlled trials (RCTs) of biologics, fevipiprant and bronchial thermoplasty.

METHODS

We followed the guidelines on the Preferred Reporting Items for Systematic reviews and Meta-Analysis (PRISMA) statement. Of the 2380 retrieved articles, 52 studies were identified for inclusion.

RESULTS

Sixty-three percent included an asthma HRQoL questionnaire. It was a secondary outcome in the majority of cases (73%). The proportion of studies including an asthma HRQoL questionnaire did not change significantly over a 20-year period. While the Asthma Quality of Life Questionnaire (AQLQ) was used in 45% of studies, 55% used a variety of 4 questionnaires. Most (70%) of the studies that included a HRQoL questionnaire did not report its subscale scores. Approximately half (52%) of studies that used HRQoL reported this in the abstract of the paper. A higher proportion of studies used an asthma control questionnaire compared to a HRQoL questionnaire (71% vs 63%).

CONCLUSION

In order to increase the use of asthma HRQoL questionnaires in RCTs of severe asthma treatments, the drivers and barriers to their use must first be understood. At present, the patients' perspective is underrepresented in RCTs of biologics, fevipiprant and bronchial thermoplasty for severe asthma.

Bronchial Thermoplasty in Patients with Severe Persistent Asthma: A Literature Review

The literature review aimed to see the safety and efficacy of bronchial thermoplasty in patients with severe asthma. We searched the online database, PUBMED, using bronchial thermoplasty and asthma as the key words and including trials from 2007 to 2021. Our review found that bronchial thermoplasty reduces asthma-related hospitalizations, emergency room visits and asthma exacerbations with sustained benefits for 5-10 years. This came at the expense of increased asthma-related adverse events, most commonly during the 7 days immediately after the procedure. Adverse events from 6 weeks after procedure to up to 5 years were similar between the bronchial thermoplasty group and the medication-only group. Bronchial thermoplasty is a safe and efficacious treatment modality for patients with severe asthma.

Airway smooth muscle pathophysiology in asthma

The airway smooth muscle (ASM) cell plays a central role in the pathogenesis of asthma and constitutes an important target for treatment. These cells control muscle tone and thus regulate the opening of the airway lumen and air passage. Evidence indicates that ASM cells participate in the airway hyperresponsiveness as well as the inflammatory and remodeling processes observed in asthmatic subjects. Therapeutic approaches require a comprehensive understanding of the structure and function of the ASM in both the normal and disease states. This review updates current knowledge about ASM and its effects on airway narrowing, remodeling, and inflammation in asthma.

Targeting Airway Smooth Muscle Hypertrophy in Asthma: An Approach Whose Time Has Come

Airway smooth muscle (ASM) cell dysfunction is an important component of several obstructive pulmonary diseases, particularly asthma. External stimuli such as allergens, dust, air pollutants, and change in environmental temperatures provoke ASM cell hypertrophy, proliferation, and migration without adequate mechanistic controls. ASM cells can switch between quiescent, migratory, and proliferative phenotypes in response to extracellular matrix proteins, growth factors, and other soluble mediators. While some aspects of airway hypertrophy and remodeling could have beneficial effects, in many cases these contribute to a clinical phenotype of difficult to control asthma. In this review, we discuss the factors responsible for ASM hypertrophy and proliferation in asthma, focusing on cytokines, growth factors, and ion transporters, and discuss existing and potential approaches that specifically target ASM hypertrophy to reduce the ASM mass and improve asthma symptoms. The goal of this review is to highlight strategies that appear ready for translational investigations to improve asthma therapy.

Severe Adult Asthmas: Integrating Clinical Features, Biology, and Therapeutics to Improve Outcomes

Evaluation and effective management of asthma, and in particular severe asthma, remains at the core of pulmonary practice. Over the last 20-30 years, there has been increasing appreciation that "severe asthma" encompasses multiple different subgroups or phenotypes, each with differing presentations. Using clinical phenotyping, in combination with rapidly advancing molecular tools and targeted monoclonal antibodies (human knockouts), the understanding of these phenotypes, and our ability to treat them, have greatly advanced. Type-2 (T2)-high and -low severe asthmas are now easily identified. Fractional exhaled nitric oxide and blood eosinophil counts can be routinely employed in clinical settings to identify these phenotypes and predict responses to specific therapies, meeting the initial goals of precision medicine. Integration of molecular signals, biomarkers, and clinical responses to targeted therapies has enabled identification of critical molecular pathways and, in certain phenotypes, advanced them to near-endotype status. Despite these advances, little guidance is available to determine which class of biologic is appropriate for a given patient, and current "breakthrough" therapies remain expensive and even inaccessible to many patients. Many of the most severe asthmas, with and without T2-biomarker elevations, remain poorly understood and treated. Nevertheless, conceptual understanding of "the severe asthmas" has evolved dramatically in a mere 25 years, leading to dramatic improvements in the lives of many.