Treatable traits in asthma: moving beyond diagnostic labels

Choosing the right biologic treatment for individual patients with severe asthma - lessons learnt from Picasso

Severe asthma represents a true challenge for clinicians from two basic perspectives, i.e.: a rational assessment of the underlying endo/phenotype and the subsequent selection of the best fitted (personalized) and effective treatment. Even though asthma is a heterogeneous disease, in the majority of therapy-compliant patients, it is possible to achieve (almost) complete disease control or even remission through conventional and quite uniform step-based pharmacotherapy, even without phenotyping. However, the absence of deeper assessment of individual patients revealed its handicap to its fullest extent during the first years of the new millennium upon the launch of biological therapeutics for patients with the most severe forms of asthma. The introduction of differentially targeted biologics into clinical practice became a challenge in terms of understanding and recognizing the etiopathogenetic heterogeneity of the asthmatic inflammation, pheno/endotyping, and, consequently, to choose the right biologic for the right patient. The answers to the following three questions should lead to correct identification of the dominant pheno/endotype: Is it really (severe) asthma? Is it eosinophilic asthma? If eosinophilic, is it (predominantly) allergen-driven? The identification of the best achievable and relevant alliance between endotypes and phenotypes ("euphenotypes") should be based not only on the assessment of the actual clinical characteristics and laboratory biomarkers, but more importantly, on the evaluation of their development and changes over time. In the current paper, we present a pragmatic three-step approach to severe asthma diagnosis and management.

Treatable traits in pre-COPD: Time to extend the treatable traits paradigm beyond established disease

To date, the treatable traits (TTs) approach has been applied in the context of managing diagnosed diseases. TTs are clinical characteristics and risk factors that can be identified clinically and/or biologically, and that merit treatment if present. There has been an exponential increase in the uptake of this approach by both researchers and clinicians. Realizing the potential of the TTs approach to pre-clinical disease, this expert review proposes that it is timely to consider acting on TTs present before a clinical diagnosis is made, which might help to prevent development of the full disease. Such an approach is ideal for diseases where there is a long pre-clinical phase, such as in chronic obstructive pulmonary disease (COPD). The term 'pre-COPD' has been recently proposed to identify patients with respiratory symptoms and/or structural or functional abnormalities without airflow limitation. They may eventually develop airflow limitation with time but patients with pre-COPD are likely to have traits that are already treatable. This review first outlines the contribution of recently generated knowledge into lifetime lung function trajectories and the conceptual framework of 'GETomics' to the field of pre-COPD. GETomics is a dynamic and cumulative model of interactions between genes and the environment throughout the lifetime that integrates information from multi-omics to understand aetiology and mechanisms of diseases. This review then discusses the current evidence on potential TTs in pre-COPD patients and makes recommendations for practice and future research. At a broader level, this review proposes that introducing the TTs in pre-COPD may help reenergize the preventive approaches to health and diseases.

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.

Evaluation of physical activity before and after respiratory rehabilitation in normal weight individuals with asthma: a feasibility study

Background

Individuals with asthma spend less time engaging in physical activity compared to the general population. Increasing physical activity has become a patient-centered goal for the treatment of treatable traits of individuals with asthma. There are data showing the possible effects of a pulmonary rehabilitation program on physical activity in obese individuals with asthma but not in normal-weight asthmatics. The objective of this feasibility study is to estimate the number of daily steps and time spent on activity in normal-weight individuals with asthma, measured before and after a pulmonary rehabilitation program.

Methods

Normal-weight individuals with moderate to severe asthma were evaluated. The individuals measured their daily steps with an accelerometer for 5 days before and after a pulmonary rehabilitation program. The study was registered on ClinicalTrials.gov: NCT05486689.

Results

In total, 17 participants were enrolled; one dropout and data on the time in activity of two individuals are missing due to a software error during the download. Data from 16 patients were analyzed. The median number of steps/day at baseline was 5,578 (25th, 75th percentiles = 4,874, 9,685) while the median activity time was 214 min (25th, 75th percentiles = 165, 239). After the rehabilitation program, the number of daily steps increased by a median value of 472 (p-value = 0.561) and the time in activity reduced by 17 min (p-value = 0.357). We also found a significant difference in quality of life, muscle strength, and exercise capacity.

Conclusions

The results of this study make it possible to calculate the sample size of future studies whose main outcome is daily steps in normal-weight individuals with asthma. The difficulties encountered in downloading time in activity data do not allow the same for this outcome.

Clinical Trial Registration

ClinicalTrials.gov, identifier NCT05486689.

Barriers to clinical remission in severe asthma

Severe asthma is associated with an increased risk for exacerbations, reduced lung function, fixed airflow obstruction, and substantial morbidity and mortality. The concept of remission in severe asthma as a new treatment goal has recently gained attention due to the growing use of monoclonal antibody therapies, which target specific pathologic pathways of inflammation. This review evaluates the current definitions of asthma remission and unveils some of the barriers for achieving this state in the severe asthma population. Although there is no unified definition, the concept of clinical remission in asthma should be based on a sustained period of symptom control, elimination of oral corticosteroid exposure and exacerbations, and stabilization of pulmonary function. The conjugation of these criteria seems a realistic treatment target in a minority of asthmatic patients. Some unmet needs in severe asthma may affect the achievement of clinical remission. Late intervention with targeted therapies in the severe asthma population may increase the risk of corticosteroid exposure and the development of irreversible structural airway changes. Moreover, airway infection is an important component in persistent exacerbations in patients on biologic therapies. Phenotyping exacerbations may be useful to guide therapy decisions and to avoid the liberal use of oral corticosteroids. Another challenge associated with the aim of clinical remission in severe asthma is the multifaceted interaction between the disease and its associated comorbidities. Behavioural factors should be evaluated in case of persistent symptoms despite optimised treatment, and assessing biomarkers and targeting treatable traits may allow for a more objective way of reaching remission. The concept of clinical remission will benefit from an international consensus to establish unifying criteria for its assessment, and it should be addressed in the future management guidelines.

Treatable Traits in Asthma: The Importance of Extrapulmonary Traits-GERD, CRSwNP, Atopic Dermatitis, and Depression/Anxiety

Treatable traits is a personalized medicine approach to the management of airway disease. Assessing traits within the 3 domains of pulmonary, extrapulmonary, and behavioral/lifestyle/risk factor traits, and applying targeted treatments to effectively manage these traits, enables a holistic and personalized approach to care. Asthma is a heterogeneous and complex airway disease that is frequently complicated by several extrapulmonary traits that impact asthma outcomes and predict future outcomes. We propose that the identification of extrapulmonary and behavioral risk factor traits and the implementation of targeted therapy will lead to improved management of people with asthma. Furthermore, many extrapulmonary traits present as "connected comorbidities"; that is, they coexist with asthma, have an impact on asthma, and effective treatment improves both asthma and the comorbidity or the comorbidities may share a similar mechanism. In this review, we explore this concept and look at atopic dermatitis, chronic rhinosinusitis with nasal polyps, gastroesophageal reflux disease, anxiety, and depression as treatable traits of asthma and how these can be managed using this approach.

Biologics (mepolizumab and omalizumab) induced remission in severe asthma patients

BACKGROUND

Asthma remission has emerged as a potential treatment goal. This study evaluated the effectiveness of two biologics (mepolizumab/omalizumab) in achieving asthma remission.

METHODS

This observational study included 453 severe asthma patients (41% male; mean age ± SD 55.7 ± 14.7 years) from two real-world drug registries: the Australian Mepolizumab Registry and the Australian Xolair Registry. The composite outcome clinical remission was defined as zero exacerbations and zero oral corticosteroids during the previous 6 months assessed at 12 months and 5-item Asthma Control Questionnaire (ACQ-5) ≤1 at 12 months. We also assessed clinical remission plus optimization (post-bronchodilator FEV1 ≥80%) or stabilization (post-bronchodilator FEV1 not greater than 5% decline from baseline) of lung function at 12 months. Sensitivity analyses explored various cut-offs of ACQ-5/FEV1 scores. The predictors of clinical remission were identified.

RESULTS

29.3% (73/249) of AMR and 22.8% (37/162) of AXR cohort met the criteria for clinical remission. When lung function criteria were added, the remission rates were reduced to 25.2% and 19.1%, respectively. Sensitivity analyses identified that the remission rate ranged between 18.1% and 34.9% in the AMR cohort and 10.6% and 27.2% in the AXR cohort. Better lung function, lower body mass index, mild disease and absence of comorbidities such as obesity, depression and osteoporosis predicted the odds of achieving clinical remission.

CONCLUSION

Biologic treatment with mepolizumab or omalizumab for severe asthma-induced asthma remission in a subgroup of patients. Remission on treatment may be an achievable treatment target and future studies should consider remission as an outcome measure.

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

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

Treatable traits models of care

Treatable traits is a personalized approach to the management of respiratory disease. The approach involves a multidimensional assessment to understand the traits present in individual patients. Traits are phenotypic and endotypic characteristics that can be identified, are clinically relevant and can be successfully treated by therapy to improve clinical outcomes. Identification of traits is followed by individualized and targeted treatment to those traits. First proposed for the management of asthma and chronic obstructive pulmonary disease (COPD) the approach is recommended in many other areas of respiratory and now immunology medicine. Models of care for treatable traits have been proposed in different diseases and health care setting. In asthma and COPD traits are identified in three domains including pulmonary, extrapulmonary and behavioural/lifestyle/risk-factors. In bronchiectasis and interstitial lung disease, a fourth domain of aetiological traits has been proposed. As the core of treatable traits is personalized and individualized medicine; there are several key aspects to treatable traits models of care that should be considered in the delivery of care. These include person centredness, consideration of patients' values, needs and preferences, health literacy and engagement. We review the models of care that have been proposed and provide guidance on the engagement of patients in this approach to care.

Treatable traits in asthma during pregnancy: a call for a shift towards a precision-based management approach

Asthma is the most common chronic medical condition in pregnancy. Asthma exacerbations in pregnancy are unpredictable, and are associated with adverse maternal and fetal perinatal outcomes such as preterm birth and low birthweight. Goals of asthma management in pregnancy are to establish effective asthma control and prevent exacerbations. Optimising the management of asthma in pregnancy is an important goal of practice and future research.Treatable traits is a precision medicine paradigm proposed for the management of airways diseases, which holistically addresses the complexity and heterogeneity of airways disease. It is an individualised treatment approach that aims to improve outcomes. This makes treatable traits well suited for pregnant women with asthma, who have a high prevalence of obesity, mental health conditions, poor symptom perception and suboptimal asthma management skills including low treatment adherence. These traits are measurable and treatable. In this review, we explore current knowledge on the burden of asthma, maternal and perinatal consequences of asthma during pregnancy, the treatable traits paradigm, the prevalence of treatable traits in pregnant women with asthma, and consider how the treatable traits paradigm can be integrated into the management of asthma in pregnancy.

An update on asthma diagnosis

OBJECTIVE

Asthma imposes a significant health and socioeconomic burden with an average prevalence impacting 5-10% of the global population. The aim of this narrative review is to update the current literature on topics related to asthma diagnosis.

DATA SOURCES

Original research articles were identified from PubMed using the search terms "asthma diagnosis" and "asthma misdiagnosis".

STUDY SELECTIONS

Recently published articles (n = 51) detailing the diagnosis, misdiagnosis of asthma, and the updated recommendations of the European and international asthma guidelines.

RESULTS

Emerging evidence revealed that asthma might represent a rather heterogenous clinical entity with varying underlying molecular mechanisms. Attempts have been made to unravel these traits to better provide accurate diagnosis and a more efficient patient-based management approach. The lack of a gold standard test for asthma diagnosis has contributed to its over- and underdiagnosis. This is problematic, given that overdiagnosis might lead to delay of both diagnosis and prompt treatment of other diseases, while underdiagnosis might substantially impact quality of life due to progression of asthma by increased rate of exacerbations and airway remodeling. In addition to poor asthma control and potential patient harm, asthma misdiagnosis is also associated with excessive costs. As a result, current international guidelines emphasize the need for a standardized approach to diagnosis, including objective measurements prior to treatment.

CONCLUSION

Future research is warranted to define the optimal diagnostic and treatable traits approach especially for patients with severe asthma, as they may benefit from the advent of newly targeted asthma management.

Perception of Illness and Fear of Inhaled Corticosteroid Use among Parents of Children with Asthma

The most prevalent children's chronic disease worldwide is asthma which has notable negative impacts on patients' and parent's quality of life. Daily inhaled corticosteroids (ICS) therapy is a preferred controller choice. This study was conducted on 148 parents of asthmatic children to establish parents' perception of illness and fear of inhaled corticosteroids using B-IPQ and TOPICOP questionnaires. Children were in the majority male (66.9%), older than five years (58.8%), with comorbidities, and family history of atopy. Parents were female, with a mean age of 38, employed, and with a history of some form of corticosteroid use. Most parents were not afraid of ICS usage (71.6%). Unemployed parents and parents who had no medical education had a statistically significantly higher fear of using ICS (p = 0.002, p = 0.03). A child's illness affects the parents' lives and parents who are afraid of using ICS react more emotionally to the child's illness. Better understanding and less concerned about child's disease are parents of children with controlled asthma. The parents' perspective of children's asthma will affect the duration and dose of ICS treatment they will give to their children and directly influence the level of asthma control.

Treatable traits: a comprehensive precision medicine approach in interstitial lung disease

Interstitial lung disease (ILD) is a diverse group of inflammatory and fibrotic lung conditions causing significant morbidity and mortality. A multitude of factors beyond the lungs influence symptoms, health-related quality of life, disease progression and survival in patients with ILD. Despite an increasing emphasis on multidisciplinary management in ILD, the absence of a framework for assessment and delivery of comprehensive patient care poses challenges in clinical practice. The treatable traits approach is a precision medicine care model that operates on the premise of individualised multidimensional assessment for distinct traits that can be targeted by specific interventions. The potential utility of this approach has been described in airway diseases, but has not been adequately considered in ILD. Given the similar disease heterogeneity and complexity between ILD and airway diseases, we explore the concept and potential application of the treatable traits approach in ILD. A framework of aetiological, pulmonary, extrapulmonary and behavioural and lifestyle treatable traits relevant to clinical care and outcomes for patients with ILD is proposed. We further describe key research directions to evaluate the application of the treatable traits approach towards advancing patient care and health outcomes in ILD.

Small molecule metabolites: discovery of biomarkers and therapeutic targets

Metabolic abnormalities lead to the dysfunction of metabolic pathways and metabolite accumulation or deficiency which is well-recognized hallmarks of diseases. Metabolite signatures that have close proximity to subject's phenotypic informative dimension, are useful for predicting diagnosis and prognosis of diseases as well as monitoring treatments. The lack of early biomarkers could lead to poor diagnosis and serious outcomes. Therefore, noninvasive diagnosis and monitoring methods with high specificity and selectivity are desperately needed. Small molecule metabolites-based metabolomics has become a specialized tool for metabolic biomarker and pathway analysis, for revealing possible mechanisms of human various diseases and deciphering therapeutic potentials. It could help identify functional biomarkers related to phenotypic variation and delineate biochemical pathways changes as early indicators of pathological dysfunction and damage prior to disease development. Recently, scientists have established a large number of metabolic profiles to reveal the underlying mechanisms and metabolic networks for therapeutic target exploration in biomedicine. This review summarized the metabolic analysis on the potential value of small-molecule candidate metabolites as biomarkers with clinical events, which may lead to better diagnosis, prognosis, drug screening and treatment. We also discuss challenges that need to be addressed to fuel the next wave of breakthroughs.

Treatable Traits in Airway Disease: From Theory to Practice

Chronic airway diseases such as asthma and chronic obstructive pulmonary disease are prevalent and complex conditions that often coexist in the same patient. To address this complexity in clinical practice, and to move forward toward personalized and precision medicine of airway diseases, a strategy based on the identification and treatment of so-called "treatable traits" (TTs) has been proposed. A TT is a recognizable phenotypic or endotypic characteristic that can be assessed and successfully targeted by therapy to improve a clinical outcome in a patient with airway disease. Importantly, TTs can coexist in the same patient, so they are not mutually exclusive. The TT strategy proposes to investigate in each individual patient with chronic airway disease the number and type of TTs present and to treat each of them according to guideline recommendations. This strategy is agnostic (ie, independent) to the traditional diagnostic labels (asthma, chronic obstructive pulmonary disease), so it can be applied to any patient with airway disease. Currently, there is firm evidence supporting the adequacy and validity of the TT strategy. Here, we review the current state of the art of this topic, first by presenting its theoretical background and then by discussing how to best implement it in clinical practice.

News in respiratory medicine

Pneumology and phthisiology (respiratory medicine) has undergone dynamic development in the last two decades. The main focus of pulmonology in the past was care for patients with tuberculosis and pneumonia. Since then, respiratory medicine evolved and the current focus is on chronic pulmonary diseases, including chronic obstructive pulmonary disease, bronchial asthma, interstitial lung diseases, but also on acute lung conditions (e.g., pneumonia, pleural diseases, respiratory failure), pneumooncology or highly specialized care for rare lung diseases (e.g., cystic fibrosis, rare interstitial diseases). Bronchology, interventional pneumology and pulmonary function testing are also important components of respiratory medicine. The importance of respiratory medicine was apparent during the COVID-19 pandemic. In this article, we provide a brief overview of the most important news to the field of respiratory medicine in the year 2022, addressing the thematic areas of bronchology, cystic fibrosis, chronic obstructive pulmonary disease, asthma, interstitial lung diseases, pleural diseases, pneumooncology, tuberculosis and non-tuberculous mycobacteria.

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

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