Treatable Traits in COPD - A Proposed Approach

Recommendations for Improving Discharge-Related Care Following a COPD Exacerbation: An Expert Panel Consensus with Emphasis on Low- and Middle-Income Countries

Exacerbations of chronic obstructive pulmonary disease (COPD) continue to place a considerable disease and financial burden on both patients and healthcare systems, particularly in low- and middle-income countries (LMICs). Therefore, preventing future exacerbations remains a key treatment goal. However, gaps remain in the standard of COPD care following exacerbations, despite the availability of evidence-based recommendations providing guidance on discharging patients from hospital or emergency department (ED) after a COPD exacerbation. To better understand these gaps in clinical practice, an advisory board meeting of 13 international pulmonologists was convened in September 2022, with the principal objective to formulate and recommend an evidence-based hospital discharge protocol following a COPD exacerbation, with a particular focus on LMICs. Based on identified gaps in COPD care, recommendations for alleviating the burden of exacerbations were proposed, which could be delivered as a discharge protocol for implementation in hospitals and/or ED. Following a review of the available clinical evidence, including an online survey of 11 pre-meeting questions and 5 additional questions discussed during the meeting, the key unmet needs identified by the experts included poor integration of standardized protocols in routine clinical practice, failure to ensure consistent delivery of post-discharge care, and lack of efficiently functioning healthcare systems. A protocol was formulated for delivery as part of a disease management program involving an interdisciplinary approach and a care bundle, aiming to address gaps in discharge-related care by determining the likelihood of readmission and optimizing maintenance treatment plans based on assessment of symptoms and future exacerbation risk. This can provide holistic care following hospital/ED discharge and personalized treatment plans by advocating referral to a specialist. To ensure wide-ranging uptake, implementation of a discharge protocol will need to be tailored to local healthcare settings by conducting feasibility studies, standardizing clinical pathways and healthcare policies, and engaging relevant stakeholders.

Pulmonary function tests: an integrated approach to interpreting results in the search for treatable traits

INTRODUCTION

Technological advances have led to the proliferation of lung function assessment techniques beyond spirometry in most countries. At the same time, new knowledge of respiratory physiology has allowed an expansion of lung function parameters, requiring an integrated approach to interpreting results.

AREAS COVERED

This review addresses the major pulmonary function tests (PFTs) used in clinical practice, new concepts regarding reference values, and reformulations of terminology for defining standards of lung function impairment. It highlights the complexities and nuances inherent in the interpretation of PFT parameters, particularly in light of recent updates from the European Respiratory Society/American Thoracic Society.

EXPERT OPINION

In a new paradigm, PFTs should be used to classify the pathophysiology of treatable traits rather than to diagnose respiratory disease, given the considerable variation in the clinical patterns of PFTs. It is necessary to look not only at lung mechanics but also at lung volume, gas transfer, and small airway involvement to capture as much information as possible. In this context, it is also important to understand that racial/ethnic differences in lung function are not due to biological differences but may reflect socioeconomic status and represent health disparities.

Chronic obstructive pulmonary disease's eosinophilic phenotype: Clinical characteristics, biomarkers and biotherapy

COPD is a chronic, heterogeneous inflammatory disorder of the airways with persistent and poorly reversible airflow limitation, causing symptoms such as cough, shortness of breath, and sputum production. Despite optimal treatment, some patients remain symptomatic due to the disease's heterogeneity, manifesting in various phenotypes. One notable phenotype involves eosinophilic inflammation, with a variable prevalence. Identifying eosinophilic phenotypes is crucial for tailored therapeutic strategies, as they respond favorably to corticosteroids and potentially biologics. Recent advances in both clinical trials and spontaneous research have helped understand the biological and clinical characteristics of this phenotype, although no universal consensus has been reached yet on the definition of the cut-off values of the eosinophil peripheral blood count. Moreover, there is evidence of novel emerging biomarkers which might go beyond the sole eosinophil count, while significant advancements in terms of pharmacological treatment have been made, with dupilumab being the first biological drug being licensed for COPD patients with elevated circulating eosinophils in the stable phase. In light of the above, although several papers have been written on the relationship between eosinophils and COPD, in the present work we endeavored to summarize and discuss the pivotal literature findings regarding the eosinophilic COPD in order to help define the biological and clinical features of this peculiar phenotype, with particular attention to the use of established and emerging biomarkers, as well as current and future therapeutic perspectives.

The precision medicine strategy to treat COPD pulmonary traits in clinical practice: The role of N-acetylcysteine

Chronic obstructive pulmonary disease (COPD) is a progressive lung condition and a leading cause of physical decline and death. COPD prevalence is expected to increase steadily in the coming years, and as a result, the healthcare and social burden of this condition will intensify. In this scenario, a patient-centric approach, the treatable trait (TT) strategy, based on the identification of traits that are clinically relevant, identifiable, monitorable and treatable, has emerged. The TT strategy, which considers behavioral/risk factors, as well as pulmonary and extrapulmonary traits, has shown to be a promising strategy in COPD management. This work reviews the TT strategy in COPD, giving special attention to the most relevant pulmonary traits, such as frequent productive cough, chronic bronchitis, type 2 inflammation, neutrophilic inflammation, lung hyperinflation, bronchiectasis, exacerbations and non-reversible airflow limitation. N-acetylcysteine (NAC), a widely used mucolytic agent, might be a major player in this strategy. Indeed, through a thorough review of the literature, it has been possible to highlight that, besides being essential in the treatment of frequent productive cough, NAC could bring benefits in case of airflow limitations, airways inflammation, exacerbations and bronchiectasis. A clinical case in which the TT strategy was able to reduce symptoms and improve lung function and quality of life, minimizing unnecessary medication and side effects, is also presented. The identification of TTs and their proper treatment through personalized medicine remarkably ameliorates COPD management. Of note, the mucolytic, antioxidant, and anti-inflammatory activities of NAC might have beneficial effects on several TTs.

Understanding the Gaps in the Reporting of COPD Exacerbations by Patients: A Review

Exacerbations of chronic obstructive pulmonary disease (COPD) are associated with loss of lung function, poor quality of life, loss of exercise capacity, risk of serious cardiovascular events, hospitalization, and death. However, patients underreport exacerbations, and evidence suggests that unreported exacerbations have similar negative health implications for patients as those that are reported. Whilst there is guidance for physicians to identify patients who are at risk of exacerbations, they do not help patients recognise and report them. Newly developed tools, such as the COPD Exacerbation Recognition Tool (CERT) have been designed to achieve this objective. This review focuses on the underreporting of COPD exacerbations by patients, the factors associated with this, the consequences of underreporting, and potential solutions.

Personalized COPD Care: The Future of Precision-Based Therapies

Chronic obstructive pulmonary disease (COPD) is a progressive respiratory illness characterized by long-standing respiratory symptoms and airflow limitation. It is a major contributor to respiratory disease-related deaths and currently ranked as the sixth leading cause of mortality in the United States. Approved pharmacological therapies for the stable disease primarily consist of inhaled short and long-acting bronchodilators, inhaled corticosteroids, azithromycin, and roflumilast. In recent years, significant progress has been made in the management of COPD through the identification of different COPD phenotypes and endotypes, which allows for a more personalized treatment approach. While earlier studies investigating targeted therapies were less promising, recent data on drugs targeting type 2 inflammatory pathways have shown promising results in carefully selected patients. In this article, we will review the available data on targeted therapies as well as the ongoing clinical studies of novel targeted therapies for COPD. Understanding and implementing these advancements hold promise for improving outcomes and quality of life for individuals living with COPD.

Tracking COPD exacerbation patterns and forecasting readmission risks utilizing electronic medical records

INTRODUCTION

Accurate evaluation of exacerbation frequency is an essential part of COPD assessment. But relying on just the prior-year exacerbation history may not capture the full picture of risk given the inherent year-to-year fluctuations in exacerbation rates. This study aimed to evaluate the predictive performance of models incorporating the 3-year exacerbation history based on electronic medical record.

MATERIALS AND METHODS

This retrospective cohort study included 86,501 COPD hospitalized patients in Beijing from 2008 to 2014. The annual frequency of COPD exacerbation hospitalizations over a 3-year period after the index hospitalization was calculated, with patients segmented into seven distinct exacerbation trajectory groups. Logistic regression was used to evaluate the predictive capability of the 3-year exacerbation history for exacerbation readmission in the fourth year. Predictors included age, sex, comorbidities, and exacerbation hospitalization in previous 1-3 years. Model performance was evaluated using area under the receiver operating characteristic curve (AUC).

RESULTS

Of the studied patients, 56.5% were men, and the mean age (SD) was 73.8 (10.3) years. The overall readmission rate for COPD exacerbation was 0.31 per person-year, with only 3.8% of patients persistently readmitted over three consecutive years. The 3-year trajectory of exacerbation frequency was associated with exacerbation risk in the fourth year. Compared to just the prior year, the inclusion of a 3-year exacerbation hospitalization history notably improved prediction accuracy, with AUC elevating from 0.731 (0.724-0.739) to 0.786 (0.779-0.792).

CONCLUSION

These results unveil the fluctuating nature of COPD exacerbation hospitalization frequency across years and demonstrate that integrating a more comprehensive 3-year exacerbation history significantly refines the prediction model for future risk, thus providing a more nuanced and actionable insight for clinical care.

Unravelling the complex interplay of factors behind exercise limitations and physical inactivity in COPD

Exercise limitation and physical inactivity are known treatable traits for people with COPD. Maximising exercise capacity and keeping people physically active improves health status and survival rates among people with COPD. However, managing these two treatable traits can be extremely challenging for clinicians due to the complex intersectionality of factors influencing an individual's capacity, opportunity and motivation to engage in physical activity. This review presents the complex factors influencing exercise capacity ("can do"), levels of physical activity ("do do") and sedentary behaviours amongst people with COPD and provides practical recommendations on how clinicians can address some of these factors in practice. Most importantly, it highlights the importance of referring to pulmonary rehabilitation as a way to improve exercise capacity among people with COPD.

Phenotype to Treatable Traits-Based Management in Chronic Obstructive Pulmonary Disease

Chronic obstructive pulmonary disease (COPD), a heterogeneous respiratory disease driven by various genetic and environmental factors, presents significant challenges in diagnosis and management. Traditional approaches focused on phenotypic classification, but recent paradigms emphasize identifying and addressing treatable traits to personalize treatment strategies. Treatable traits facilitate personalized interventions, optimizing symptom control, and reducing exacerbation risk. Dyspnea and exacerbations, recognized as key traits, guide treatment decisions and follow-up management. Various interventions, including bronchodilators, corticosteroids, and lifestyle modifications, target specific traits like airway inflammation, mucus overproduction, and emphysema. Strategies for assessing and addressing treatable traits during initial encounters and follow-up visits enhance disease monitoring and treatment efficacy. Comprehensive trait assessment demands resources and specialized monitoring, posing barriers to widespread implementation. The lack of standardized protocols and evolving evidence further complicates decision-making and clinical practice. Despite these challenges, the shift toward treatable traits-based management signifies a pivotal advancement in COPD care, emphasizing holistic approaches tailored to individual patient needs. Recognizing and addressing treatable traits offers personalized interventions, enhancing symptom control and disease management. Embracing treatable traits-based approaches holds promise for improving clinical outcomes and enhancing the quality of life for individuals living with COPD.

N-acetylcysteine Treatment in Chronic Obstructive Pulmonary Disease (COPD) and Chronic Bronchitis/Pre-COPD: Distinct Meta-analyses

INTRODUCTION

N-acetylcysteine (NAC) is a mucolytic agent with antioxidant properties. Oxidative stress is a key pathogenic mechanism in chronic respiratory conditions such as COPD and chronic bronchitis (CB). In these meta-analyses we investigated the efficacy of NAC in subjects with COPD or CB, the latter being a potential pre-COPD condition (CB/pre-COPD).

METHODS

The meta-analyses were conducted according to PRISMA guidelines. Exacerbations were assessed using total number of exacerbations. Improvement in patients' respiratory symptoms and/or patients quality of life (QoL) were measured by validated tools or assessed at the end of the study.

RESULTS

Twenty studies were included, of which seven evaluated NAC in patients with symptoms of CB/pre-COPD as entry criterion. NAC treated patients showed a significant reduction of the incidence of exacerbations as compared to placebo both in COPD (IRR=0.76; 95% confidence interval (CI) 0.59-0.99) and CB/pre-COPD (IRR=0.81; 95% CI 0.69-0.95). Sensitivity analyses in studies with duration higher than 5 months, confirmed the overall results. CB/pre-COPD patients treated with NAC were significantly more likely to experience an improvement in symptoms and/or QoL compared to placebo (odds ratio (OR)=3.47; 95% CI 1.92-6.26). A similar trend was observed in the few COPD studies evaluable. Sensitivity analyses showed a significant association of NAC with improvement in symptoms and/or QoL both in CB/pre-COPD and COPD patients.

CONCLUSIONS

These findings provide novel data of NAC on the improvement in symptoms and QoL in addition to prevention of exacerbations in COPD and CB/pre-COPD. PROSPERO registry no. CRD42023468154.

Predicting parameters of airway dynamics generated from inspiratory and expiratory plethysmographic airway loops, differentiating subtypes of chronic obstructive diseases

BACKGROUND

The plethysmographic shift volume-flow loop (sRaw-loop) measured during tidal breathing allows the determination of several lung function parameters such as the effective specific airway resistance (sReff), calculated from the ratio of the integral of the resistive aerodynamic specific work of breathing (sWOB) and the integral of the corresponding flow-volume loop. However, computing the inspiratory and expiratory areas of the sRaw-loop separately permits the determination of further parameters of airway dynamics. Therefore, we aimed to define the discriminating diagnostic power of the inspiratory and expiratory sWOB (sWOBin, sWOBex), as well as of the inspiratory and expiratory sReff (sReff IN and sReff EX), for discriminating different functional phenotypes of chronic obstructive lung diseases.

METHODS

Reference equations were obtained from measurement of different databases, incorporating 194 healthy subjects (35 children and 159 adults), and applied to a collective of 294 patients with chronic lung diseases (16 children with asthma, aged 6-16 years, and 278 adults, aged 17-92 years). For all measurements, the same type of plethysmograph was used (Jaeger Würzburg, Germany).

RESULTS

By multilinear modelling, reference equations of sWOBin, sWOBex, sReff IN and sReff EX were derived. Apart from anthropometric indices, additional parameters such as tidal volume (VT), the respiratory drive (P0.1), measured by means of a mouth occlusion pressure measurement 100 ms after inspiration and the mean inspiratory flow (VT/TI) were found to be informative. The statistical approach to define reference equations for parameters of airway dynamics reveals the interrelationship between covariants of the actual breathing pattern and the control of breathing.

CONCLUSIONS

We discovered that sWOBin, sWOBex, sReff IN and sReff EX are new discriminating target parameters, that differentiate much better between chronic obstructive diseases and their subtypes, especially between chronic obstructive pulmonary disease (COPD) and asthma-COPD overlap (ACO), thus strengthening the concept of precision medicine.

ERS International Congress 2023: highlights from the Airway Diseases Assembly

In this review, early career and senior members of Assembly 5 (Airway Diseases, Asthma, COPD and Chronic Cough) present key recent findings pertinent to airway diseases that were presented during the European Respiratory Society International Congress 2023 in Milan, Italy, with a particular focus on asthma, COPD, chronic cough and bronchiectasis. During the congress, an increased number of symposia, workshops and abstract presentations were organised. In total, 739 abstracts were submitted for Assembly 5 and the majority of these were presented by early career members. These data highlight the increased interest in this group of respiratory diseases.

Assessment of functional diversities in patients with Asthma, COPD, Asthma-COPD overlap, and Cystic Fibrosis (CF)

The objectives of the present study were to evaluate the discriminating power of spirometric and plethysmographic lung function parameters to differenciate the diagnosis of asthma, ACO, COPD, and to define functional characteristics for more precise classification of obstructive lung diseases. From the databases of 4 centers, a total of 756 lung function tests (194 healthy subjects, 175 with asthma, 71 with ACO, 78 with COPD and 238 with CF) were collected, and gradients among combinations of target parameters from spirometry (forced expiratory volume one second: FEV1; FEV1/forced vital capacity: FEV1/FVC; forced expiratory flow between 25-75% FVC: FEF25-75), and plethysmography (effective, resistive airway resistance: sReff; aerodynamic work of breathing at rest: sWOB), separately for in- and expiration (sReffIN, sReffEX, sWOBin, sWOBex) as well as static lung volumes (total lung capacity: TLC; functional residual capacity: FRCpleth; residual volume: RV), the control of breathing (mouth occlusion pressure: P0.1; mean inspiratory flow: VT/TI; the inspiratory to total time ratio: TI/Ttot) and the inspiratory impedance (Zinpleth = P0.1/VT/TI) were explored. Linear discriminant analyses (LDA) were applied to identify discriminant functions and classification rules using recursive partitioning decision trees. LDA showed a high classification accuracy (sensitivity and specificity > 90%) for healthy subjects, COPD and CF. The accuracy dropped for asthma (~70%) and even more for ACO (~60%). The decision tree revealed that P0.1, sRtot, and VT/TI differentiate most between healthy and asthma (68.9%), COPD (82.1%), and CF (60.6%). Moreover, using sWOBex and Zinpleth ACO can be discriminated from asthma and COPD (60%). Thus, the functional complexity of obstructive lung diseases can be understood, if specific spirometric and plethysmographic parameters are used. Moreover, the newly described parameters of airway dynamics and the central control of breathing including Zinpleth may well serve as promising functional marker in the field of precision medicine.

Can Treatable Traits Be the Approach to Addressing the Complexity and Heterogeneity of COPD?

The complexity of COPD implies the need to identify groups of patients with similar clinical characteristics and prognosis or treatment requirements. This is why much attention has been paid to identifying the different clinical phenotypes by investigating the clinical expression of the disease, and endotypes by studying the biological networks that enable and limit reactions. However, this approach is complicated because one endotype gives rise to one or more clinical characteristics, and clinical phenotypes can be derived from several endotypes. To simplify the approach, a new taxonomic classification of COPD based on the different causes (or etiotypes) has been proposed, but these etiotypes have not yet been validated. A simpler method is the so-called tractable traits approach, which is free from any designation of the disorder to be treated and does not present the criticality of using etiotypes. A large randomised controlled trial on using the treatable traits approach in COPD is still lacking. Nevertheless, this approach is already applied by following the GOLD strategy. However, its application is complicated because several potentially treatable traits have been identified within the pulmonary domain, the extrapulmonary domain, and the behavioural/risk factor domain. In addition, the hierarchy of the dominant treatable traits has not yet been established, and they change over time both spontaneously and because of treatment. This means that the patients being treated according to the tractable traits approach must be constantly followed over time so that the therapy is focused on their temporal needs.

An Update on Outcomes for COPD Pharmacological Trials: A COPD Investigators Report - Reassessment of the 2008 American Thoracic Society/European Respiratory Society Statement on Outcomes for COPD Pharmacological Trials

Background: In 2008, a dedicated American Thoracic Society/European Respiratory Society task force published a paper on the possible use and limitations of clinical outcomes and biomarkers to evaluate the impact of pharmacological therapy in patients with chronic obstructive pulmonary disease. Since then, our scientific understanding of chronic obstructive pulmonary disease has increased considerably; there has been a progressive shift from a one-size-fits-all diagnostic and therapeutic approach to a personalized approach; and many new treatments currently in development will require new endpoints to evaluate their efficacy adequately. Objectives: The emergence of several new relevant outcome measures motivated the authors to review advances in the field and highlight the need to update the content of the original report. Methods: The authors separately created search strategies for the literature, primarily based on their opinions and assessments supported by carefully chosen references. No centralized examination of the literature or uniform criteria for including or excluding evidence were used. Measurements and Main Results: Endpoints, outcomes, and biomarkers have been revisited. The limitations of some of those reported in the American Thoracic Society/European Respiratory Society task force document have been highlighted. In addition, new tools that may be useful, especially in evaluating personalized therapy, have been described. Conclusions: Because the "label-free" treatable traits approach is becoming an important step toward precision medicine, future clinical trials should focus on highly prevalent treatable traits, and this will influence the choice of outcomes and markers to be considered. The use of the new tools, particularly combination endpoints, could help better identify the right patients to be treated with the new drugs.

Clinical Implications of Peak Inspiratory Flow in COPD: Post Hoc Analyses of the TRONARTO Study

Background

In patients with COPD, inhalation ability should be assessed when considering inhaler choice. To evaluate whether the soft mist inhaler (SMI) is suitable for COPD patients irrespective of inhalation ability, the TRONARTO study investigated the efficacy of dual long-acting bronchodilator therapy delivered via the Respimat® SMI on lung function in patients with COPD stratified by inhalation ability. Tiotropium/olodaterol delivered via the SMI was effective both in patients with peak inspiratory flow (PIF) <60 L/min and PIF ≥60 L/min, measured against medium-low resistance.

Methods

This congress compilation summarizes post hoc analyses from the TRONARTO study presented at the annual American Thoracic Society 2022 and European Respiratory Society 2022 meetings. These analyses evaluated PIF in over 200 patients, with PIF measurements taken daily at home for 4 weeks, and in the clinic at baseline, Weeks 2 and 4.

Results

Overall, 57.9% of patients had a PIF range (difference between lowest and highest PIF measurements) <20 L/min (12.4% of patients had PIF range <10 L/min). At-home PIF range decreased over the study period, suggesting that inhaler training/repeated PIF measurements may help to make patients' inspiratory effort more consistent. Some patient characteristics correlated with lower PIF (female gender, shorter stature, more severe disease, worse airflow obstruction) and lower PIF range (more severe disease). PIF measurements differed between medium-low and high-resistance settings, highlighting the importance of measuring PIF at the resistance of a patient's inhaler. PIF correlated poorly with spirometry measurements.

Conclusion

As indicated in COPD management guidelines, choice of inhaler is essential to optimize pharmacologic therapies for COPD. Poor inspiratory ability should be viewed as a treatable trait that can help to inform inhaler choice. Inhaler training and consideration of PIF (if patients use a dry powder inhaler) can reduce patient-to-inhaler mismatch, with potential consequences for health status and exacerbation risk.

Inhibition of oxidative stress by apocynin attenuated chronic obstructive pulmonary disease progression and vascular injury by cigarette smoke exposure

BACKGROUND AND PURPOSE

Cardiovascular disease affects up to half of the patients with chronic obstructive pulmonary disease (COPD), exerting deleterious impact on health outcomes and survivability. Vascular endothelial dysfunction marks the onset of cardiovascular disease. The present study examined the effect of a potent NADPH Oxidase (NOX) inhibitor and free-radical scavenger, apocynin, on COPD-related cardiovascular disease.

EXPERIMENTAL APPROACH

Male BALB/c mice were exposed to either room air (Sham) or cigarette smoke (CS) generated from 9 cigarettes·day-1 , 5 days a week for up to 24 weeks with or without apocynin treatment (5 mg·kg-1 ·day-1 , intraperitoneal injection).

KEY RESULTS

Eight-weeks of apocynin treatment reduced airway neutrophil infiltration (by 42%) and completely preserved endothelial function and endothelial nitric oxide synthase (eNOS) availability against the oxidative insults of cigarette smoke exposure. These preservative effects were maintained up until the 24-week time point. 24-week of apocynin treatment markedly reduced airway inflammation (reduced infiltration of macrophage, neutrophil and lymphocyte), lung function decline (hyperinflation) and prevented airway collagen deposition by cigarette smoke exposure.

CONCLUSION AND IMPLICATIONS

Limiting NOX activity may slow COPD progression and lower cardiovascular disease risk, particularly when signs of oxidative stress become evident.

Inhaled Corticosteroids and the Risk of Nontuberculous Mycobacterial Pulmonary Disease in Chronic Obstructive Pulmonary Disease: Findings from a Nationwide Population-Based Study

Studies have shown increased nontuberculous mycobacterial pulmonary disease (NTM) incidence with inhaled corticosteroid (ICS) use in patients with chronic respiratory diseases; however, this association in chronic obstructive pulmonary disease (COPD) remains insufficiently studied. Using a nationwide population-based database of the Korean National Health Insurance Service, newly diagnosed COPD patients (2005-2018) treated with inhaled bronchodilators were selected. An NTM case was defined by the presence of the first diagnostic code following inhaled bronchodilator use. Results indicated that ICS users did not have an increased risk of NTM disease compared to non-ICS users (hazard ratio (HR), 1.121; 95% confidence interval (CI), 0.950-1.323; p = 0.176). However, in a subgroup analysis, the highest quartile of the cumulative ICS dose was associated with the development of NTM (1.200, 0.950-1.323, p = 0.050). Medium (1.229, 1.008-1.499, p = 0.041) and high daily doses of ICS (1.637, 1.241-2.160, p < 0.001) were associated with an increased risk of NTM disease. There was no difference in the risk of NTM according to ICS type. ICS use may increase the risk of developing NTM disease in patients with COPD. Physicians should weigh the potential benefits and risks of ICS, especially when using high doses and prolonged durations.

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.

The presence of extra-pulmonary treatable traits increases the likelihood of responding to pulmonary rehabilitation

INTRODUCTION

Studies suggest that people with chronic obstructive pulmonary disease (COPD) who are worse at baseline respond better to pulmonary rehabilitation (PR). Identifying treatable traits (TTs) may help to distinguish responders from non-responders. We explored the impact of PR on extra-pulmonary traits of people with COPD and whether the presence of TT influences the type of response to PR.

METHODS

A comprehensive assessment of 9 TT including symptoms (dyspnoea, fatigue, anxiety and depression), functional capacity, deconditioning, balance, impact of the disease and health-related quality of life was conducted before and after a 12-week community-based PR programme. Pre-post differences between people with or without each TT at baseline were compared with independent samples t-tests or Mann-Whitney U tests. Proportion of responders between groups were explored with chi-square tests and odds ratio.

RESULTS

102 people with COPD were included (70 [65; 75] years old, 78% male, FEV₁ 47 [36; 60] %predicted). They had a median of 3 (out of 9) TTs per person and each patient responded on average to 5 (out of 9) outcomes of PR. People with TT were more responsive than those without them in all outcomes (p < 0.05) except for the 1-min sit-to-stand test. The presence of TT increased 4 to 20 times the likelihood of being a good responder.

CONCLUSIONS

Identification of baseline extra-pulmonary TT in people with COPD showed the potential to inform on PR responsiveness and might therefore be an important strategy for patient prioritization, treatment personalisation (i.e., activation of the most suitable components) and optimisation.

The Role of Chitinases in Chronic Airway Inflammation Associated with Tobacco Smoke Exposure

Chitinases and chitinase-like proteins are thought to play a role in innate inflammatory responses. Our study aimed to assess whether chitinase concentration and activity in induced sputum (IS) of patients exposed to tobacco smoke are related to the level of airway inflammation including the level and activity of chitinases and chitinase-like proteins. The study included 22 patients with chronic obstructive pulmonary disease (COPD), 12 non-COPD smokers, and nine nonsmoking subjects. Sputum CHIT1 and YKL-40 levels and chitinolytic activity were compared with sputum IL-6, IL-8, IL-18, and MMP-9 levels. A hierarchical cluster analysis was also performed. Sputum YKL-40 was higher in COPD patients than in the control groups. Sputum CHIT1 and YKL-40 levels correlated with IS inflammatory cell count as well as with MMP-9 and IL-8 levels. Two main clusters were revealed: Cluster 1 had lower chitinase levels and activity, lower IS macrophage and neutrophil count, and lower IS IL-8, IL-18, and MMP-9 than Cluster 2. Comparison of COPD patients from both clusters revealed significant differences in the IS inflammatory profile despite comparable clinical and functional data. Our findings seem to confirm the involvement of chitinases in smoking-associated chronic airway inflammation and show that airway chitinases may be a potential novel marker in COPD phenotyping.

Functional Predictors Discriminating Asthma-COPD Overlap (ACO) from Chronic Obstructive Pulmonary Disease (COPD)

Background

A significant proportion of patients with obstructive lung disease have clinical and functional features of both asthma and chronic obstructive pulmonary disease (COPD), referred to as the asthma-COPD overlap (ACO). The distinction of these phenotypes, however, is not yet well-established due to the lack of defining clinical and/or functional criteria. The aim of our investigations was to assess the discriminating power of various lung function parameters on the assessment of ACO.

Methods

From databases of 4 pulmonary centers, a total of 540 patients (231 males, 309 females), including 372 patients with asthma, 77 patients with ACO and 91 patients with COPD, were retrospectively collected, and gradients among combinations of explanatory variables of spirometric (FEV1, FEV1/FVC, FEF25-75), plethysmographic (sReff, sGeff, the aerodynamic work of breathing at rest; sWOB), static lung volumes, including trapped gases and measurements of the carbon monoxide transfer (DLCO, KCO) were explored using multiple factor analysis (MFA). The discriminating power of lung function parameters with respect to ACO was assessed using linear discriminant analysis (LDA).

Results

LDA revealed that parameters of airway dynamics (sWOB, sReff, sGeff) combined with parameters of static lung volumes such as functional residual capacity (FRCpleth) and trapped gas at FRC (VTG FRC) are valuable and potentially important tools discriminating between asthma, ACO and COPD. Moreover, sWOB significantly contributes to the diagnosis of obstructive airway diseases, independent from the state of pulmonary hyperinflation, whilst the diffusion capacity for carbon monoxide (DLCO) significantly differentiates between the 3 diagnostic classes.

Conclusion

The complexity of COPD with its components of interaction and their heterogeneity, especially in discrimination from ACO, may well be differentiated if patients are explored by a whole set of target parameters evaluating, interactionally, flow limitation, airway dynamics, pulmonary hyperinflation, small airways dysfunction and gas exchange disturbances assessing specific functional deficits.

Real-World Treatment of Patients Newly Diagnosed with Chronic Obstructive Pulmonary Disease: A Retrospective German Claims Data Analysis

Purpose

This study aimed to describe the real-world treatment of German incident COPD patients, compare that treatment with clinical guidelines, and provide insight into disease development after incident diagnosis. In addition, the economic burden of the disease by assessing COPD-related healthcare costs was described.

Patients and Methods

Based on a German claims dataset, continuously insured individuals (04/2014-03/2019) aged 40 years or older with at least two incident pulmonologist's diagnoses or one inpatient diagnosis of COPD (ICD-10-GM code J44.-; no respective diagnosis in a 12-month baseline period) were selected. Treatment patterns after incident diagnosis considering inhaled maintenance therapies identified by ATC codes (outpatient prescriptions) were analyzed. Prescription patterns were compared with recommendations of German COPD treatment guidelines. Severe exacerbations were assessed as hospitalizations with main diagnosis ICD-10-GM code J44.1. COPD-associated costs from the perspective of the health insurance fund AOK PLUS were calculated per patient-year (PY).

Results

The sample comprised 17,464 incident COPD patients with a mean age of 71.5 years. 58.9% were male and the mean Charlson-Comorbidity-Index was 5.3. During follow-up (median: 2.0 years), 57.1% of the patients received at least one prescription of an inhaled maintenance therapy, whereas 42.9% did not. Among treated patients, 35.2% started their treatment with LABA/LAMA, 25.3% with LAMA monotherapy, 16.2% with LABA/ICS, and 7.8% with LABA/LAMA/ICS therapy. Within four weeks after initial diagnosis, ICS-containing therapies were prescribed in 14.1% of patients. Of all patients with a prescribed triple therapy, 68.9% had no corresponding exacerbation history documented. On average, 0.16 severe exacerbations and 0.19 COPD-related hospitalizations were observed per PY during available follow-up. Direct COPD-related costs were 3,693 €/PY, with COPD-related hospitalizations being responsible for about 79.2% of these costs.

Conclusion

Long-acting bronchodilators are the mainstay of pharmacological treatment of incident COPD patients in Germany, in line with guideline recommendations. Yet, a considerable proportion of incident COPD patients did not receive any inhaled maintenance therapy.

Blood Eosinophils and Exhaled Nitric Oxide: Surrogate Biomarkers of Airway Eosinophilia in Stable COPD and Exacerbation

In recent years, tremendous efforts have been devoted to characterizing the inflammatory processes in chronic obstructive pulmonary disease (COPD) in order to provide more personalized treatment for COPD patients. While it has proved difficult to identify COPD-specific inflammatory pathways, the distinction between eosinophilic and non-eosinophilic airway inflammation has gained clinical relevance. Evidence has shown that sputum eosinophil counts are increased in a subset of COPD patients and that these patients are more responsive to oral or inhaled corticosteroid therapy. Due to feasibility issues associated with sputum cell profiling in daily clinical practice, peripheral blood eosinophil counts and fractional exhaled nitric oxide levels have been evaluated as surrogate biomarkers for assessing the extent of airway eosinophilia in COPD patients, both in stable disease and acute exacerbations. The diagnostic value of these markers is not equivalent and depends heavily on the patient’s condition at the time of sample collection. Additionally, the sensitivity and specificity of these tests may be influenced by the patient’s maintenance treatment. Overall, eosinophilic COPD may represent a distinct disease phenotype that needs to be further investigated in terms of prognosis and treatment outcomes.

The Impact of Chronic Bronchial Infection in COPD: A Proposal for Management

Up to 50% of patients with chronic obstructive pulmonary disease (COPD) in stable state may carry potentially pathogenic microorganisms (PPMs) in their airways. The presence of PPMs has been associated with increased symptoms, increased risk and severity of exacerbations, a faster decline in lung function and impairment in quality of life. Although some clinical trials have demonstrated a reduction in exacerbations in patients chronically treated with systemic antibiotics, particularly macrolides, the selection of patients was based on the previous frequency of exacerbations and not on the presence of PPMs in their airways. Therefore, unlike in bronchiectasis, there is a lack of evidence-based recommendations for assessment and treatment of the presence of PPMs in either single or repeated isolations in COPD. In this article, we propose that chronic bronchial infection (CBI) in COPD be defined as the isolation of the same PPM in at least three sputum samples separated by more than one month; we review the impact of CBI on the natural course of COPD and suggest a course of action in patients with a single isolation of a PPM or suspected CBI. Antibiotic treatment in stable COPD should be recommended based on four main criteria: a) the presence of comorbid bronchiectasis, b) the demonstration of a single or multiple isolation of the same PPM, c) the clinical impact of CBI on the patients, and d) the type of PPM, either Pseudomonas aeruginosa or non-pseudomonal PPM. These recommendations are derived from evidence generated in patients with bronchiectasis and, until new evidence specifically obtained in COPD is available, they may help in the management of these challenging patients with COPD. Existing evidence suggests that inhaled therapy is insufficient to manage patients with moderate-to-severe COPD, frequent exacerbations, and CBI. New studies must be conducted in this particularly demanding population.

Temporal trends in anxiety and depression prevalence and their association with adverse outcomes in patients hospitalized for acute exacerbations of chronic obstructive pulmonary disease in Beijing, China, from 2004 to 2020

AIMS

To investigate the temporal trend in anxiety and/or depression prevalence in patients hospitalized for acute exacerbation of chronic obstructive pulmonary disease (AECOPD) in Beijing and their association with adverse outcomes.

MATERIALS AND METHODS

Hospital admission records from 2004 to 2020 with a primary discharge diagnosis of AECOPD were retrieved from Beijing Public Health Information Centre database. The anxiety and depression were identified from discharge diagnoses of each record. Joinpoint regression was used to analyze the temporal trend and calculate the annual percentage change (APC) for the prevalence of anxiety and/or depression. Generalized linear model was used to analyze the associations between anxiety and/or depression and patients' adverse outcomes.

RESULTS

A total of 382,125 records were included, most of which were male (66.0%) and aged ≥ 75 years (59.7%). Three segments in the temporal trend were observed, with a mild increase during 2004-2009 (APC: 5.9%, 95% CI: -14.9 to 31.7%), followed by a sharply increase during 2009-2012 (APC: 60.4%, 95% CI: 10.6 to 132.7%), then stabilized at about 3% during 2012-2020 (APC: 1.9%, 95% CI: -0.4 to 4.3%). On average, anxiety, and/or depression was more prevalent in females, the aged and those admitted in secondary hospitals (all P < 0.001). Patients with anxiety and/or depression had lower in-hospital mortality (IHM) (OR = 0.74, 95% CI: 0.63-0.88), but longer hospital stay (OR = 1.10, 95% CI: 1.07-1.13), more medical costs (OR = 1.12, 95% CI: 1.08-1.17) and higher risks of readmission for AECOPD at 30-, 90-, 180-day, and 1-year (ORs ranged from 1.22 to 1.51).

CONCLUSION

The prevalence of anxiety and/or depression in patients hospitalized for AECOPD in Beijing stabilized at approximately 3% after 2012. Anxiety and/or depression is associated with a heavier burden on patients, health care, and medical insurance systems. Appropriate diagnosis and effective treatment of anxiety and depression is crucial for patients with AECOPD.