Do we really need asthma-chronic obstructive pulmonary disease overlap syndrome?

Electrocardiographic alterations in chronic obstructive pulmonary disease

Chronic obstructive pulmonary disease (COPD) is a leading cause of morbidity and mortality, and its incidence has grown within several years, quickly becoming the third leading cause of mortality. The disease is characterized by alveolar destruction, air-trapping, and chronic inflammation due to persistent exposure to a large spectrum of harmful particles. The diagnosis of COPD is made by demonstration of persistent and not fully reversible airflow limitation, and different phenotypes may be recognized based on pathophysiological, clinical, and radiological features. However, COPD is a systemic disease with effects involving several organs. For example, mechanical and functional alterations secondary to COPD involve heart function. Indeed, cardiovascular diseases are highly prevalent in patients affected by COPD and represent the primary cause of mortality in such patients. An electrocardiogram is a simple and cheap test that gives much information about the heart status of COPD patients. Consequently, variations from "normality" can be appreciated in these patients, with the most frequent abnormalities being P-wave, QRS axis, and ventricular repolarization abnormalities, in addition to conduction alterations and a vast number of arrhythmias. As a result, ECG should be routinely performed as a valuable tool to recognize alterations due to COPD (i.e., mechanical and functional) and possible associated heart diseases. This review aims to describe the typical ECG features in most COPD patients and to provide a systematic summary that can be used in clinical practice.

Undiagnosed Asthma-COPD overlap among patients diagnosed as Asthma and COPD in a referral hospital, India

Patients who have features of both Asthma & COPD are now known as Asthma COPD overlap (ACO). Prevalence of ACO based on the Global Initiative for Asthma (GINA) and Global initiative for obstructive lung disease (GOLD) Syndromic Approach is scarce. In this cross-sectional observational study, we recruited physician-diagnosed-pAsthma, pCOPD & pACO by simple random sampling. Clinical features, spirometry, 6-min walk test, Serum Immunoglobulin E, % blood eosinophils and chest x-rays were reviewed. Syndromic approach was applied, and the diagnosis was reclassified accordingly. In all, 877 patients were included (Male = 445, Female = 432). Physician diagnosis for these were: pAsthma-713, pCOPD-157 and pACO-7. They were reclassified using the Syndromic approach as: sAsthma, sCOPD and sACO. The 713 pAsthmatics were reclassified as follows: sAsthma-684 (95.94%), sCOPD-12 (1.68%) and sACO-17 (2.38%). Of the 157 pCOPD patients, 91 (57.96%) were reclassified as sCOPD, 23 (14.6%) as sACO, and 17 (927.38%) as sAsthma. Of the 7 previously diagnosed pACO patients, only 1 (14.28%) was reclassified as sACO, 5 (71.42%) as sAsthma and 1 (14.28%) as sCOPD. sCOPD patients had more exacerbations (52.88% vs 46.34%, p = 0.479), critical care admissions (16.35% vs 7.32%, p = 0.157) and intubations (17.31% vs 9.76%, p = 0.255) compared to sACO patients, the latter had more events than sAsthma patients: exacerbations 46.34% vs 10.11% (p < 0.001), critical care admissions 7.32% vs 1.64% (p = 0.010) and intubations 9.76% vs 1.5% (p < 0.001). The syndromic approach helped us to identify ACO and also more appropriately classified COPD & Asthma. There was a significant difference between physician diagnosis and diagnosis using Syndromic Approach. It revealed considerable misclassification of several Asthmatic and ACO subjects, who could have been denied inhaled corticosteroids, as they were wrongly categorised as COPD by physician diagnosis.

Pathogenesis, clinical features of asthma COPD overlap (ACO), and therapeutic modalities

Both asthma and COPD are heterogeneous diseases identified by characteristic symptoms and functional abnormalities, with airway obstruction common in both diseases. Asthma COPD overlap (ACO) does not define a single disease but is a descriptive term for clinical use that includes several overlapping clinical phenotypes of chronic airways disease with different underlying mechanisms. This literature review was initiated to describe published studies, identify gaps in knowledge, and propose future research goals regarding the disease pathology of ACO, especially the airway remodelling changes and inflammation aspects. Airway remodelling occurs in asthma and COPD, but there are differences in the structures affected and the prime anatomic site at which they occur. Reticular basement membrane thickening and cellular infiltration with eosinophils and T-helper (CD4+) lymphocytes are prominent features of asthma. Epithelial squamous metaplasia, airway wall fibrosis, emphysema, bronchoalveolar lavage (BAL) neutrophilia and (CD8+) T-cytotoxic lymphocyte infiltrations in the airway wall are features of COPD. There is no universally accepted definition of ACO, nor are there clearly defined pathological characteristics to differentiate from asthma and COPD. Understanding etiological concepts within the purview of inflammation and airway remodelling changes in ACO would allow better management of these patients.

An Overview of the Safety and Efficacy of Monoclonal Antibodies for the Chronic Obstructive Pulmonary Disease

Several mAbs have been tested or are currently under clinical evaluation for the treatment of COPD. They can be subdivided into those that aim to block specific pro-inflammatory and pro-neutrophilic cytokines and chemokines, such as TNF-α, IL-1β, CXCL8 and IL-1β, and those that act on T2-mediated inflammation, respectively, by blocking IL-5 and/or its receptor, preventing IL-4 and IL-13 signaling, affecting IL-33 pathway and blocking TSLP. None of these approaches has proved to be effective, probably because in COPD there is no dominant cytokine or chemokine and, therefore, a single mAb cannot be effective on all pathways. With a more in-depth understanding of the numerous pheno/endotypic pathways that play a role in COPD, it may eventually be possible to identify those specific patients in whom some of these cytokines or chemokines might predominate. In this case, it will be possible to implement a personalized treatment, but the use of each mAb will only be reserved for a very limited number of subjects.

ACO (Asthma-COPD Overlap) Is Independent from COPD: The Case in Favour

Over the last decade interest has been shown in people with symptomatic lung disease who have features both of COPD and asthma. In this review we examine how COPD and asthma are defined and examine clinical characteristics of people defined by researchers as having asthma-COPD overlap (ACO). We look at pathological and physiological features along with symptoms and consider the impact of each diagnosis upon therapeutic management. We highlight challenges in the diagnosis and management of airway disease and the various phenotypes that could be part of ACO, in so doing suggesting ways for the clinician to manage patients with features of both asthma and COPD.

Asthma-COPD overlap: current understanding and the utility of experimental models

Pathological features of both asthma and COPD coexist in some patients and this is termed asthma-COPD overlap (ACO). ACO is heterogeneous and patients exhibit various combinations of asthma and COPD features, making it difficult to characterise the underlying pathogenic mechanisms. There are no controlled studies that define effective therapies for ACO, which arises from the lack of international consensus on the definition and diagnostic criteria for ACO, as well as scant in vitro and in vivo data. There remain unmet needs for experimental models of ACO that accurately recapitulate the hallmark features of ACO in patients. The development and interrogation of such models will identify underlying disease-causing mechanisms, as well as enabling the identification of novel therapeutic targets and providing a platform for assessing new ACO therapies. Here, we review the current understanding of the clinical features of ACO and highlight the approaches that are best suited for developing representative experimental models of ACO.

Understanding the pathogenesis of asthma-COPD overlap is critical for improving therapeutic approaches. We present current knowledge on asthma-COPD overlap and the requirements for developing an optimal animal model of disease.https://bit.ly/3lsjyvm

The impact of comorbidities on severe asthma

PURPOSE OF REVIEW

Severe asthma is often associated with numerous comorbidities that complicate disease management and affect patient's outcomes. They contribute to poor disease control and mimic asthma symptoms. Although some comorbidities such as obstructive sleep apnea, bronchiectasis, and chronic obstructive pulmonary disease are generally well recognized, many other may remain undiagnosed but may be detected in an expert specialist setting. The management of comorbidities seems to improve asthma outcomes, and optimizes therapy by avoiding overtreatment. The present review provides recent knowledge regarding the most common comorbidities which are associated with severe asthma.

RECENT FINDINGS

Comorbidities are more prevalent in severe asthma than in mild-to-moderate disease or in the general population. They can be grouped into two large domains: the pulmonary domain and the extrapulmonary domain. Pulmonary comorbidities include upper respiratory tract disorders (obstructive sleep apnea, allergic and nonallergic rhinitis, chronic rhinosinusitis, nasal polyposis) and middle/lower respiratory tract disorders (chronic obstructive pulmonary disease, allergic bronchopulmonary aspergillosis and fungal sensitization, bronchiectasis, dysfunctional breathing). Extrapulmonary comorbidities include anxiety, depression, gastro-esophageal reflux disease, obesity, cardiovascular, and metabolic diseases.

SUMMARY

The identification of comorbidities via multidimensional approach is needed to initiate appropriate multidisciplinary management of patients with severe asthma.

Asthma with Irreversible Airway Obstruction in Smokers and Nonsmokers: Links between Airway Inflammation and Structural Changes

BACKGROUND

The development of irreversible airway obstruction (IRAO) in asthma is related to lung/airway inflammatory and structural changes whose characteristics are likely influenced by exposure to tobacco smoke.

OBJECTIVE

To investigate the interplay between airway and lung structural changes, airway inflammation, and smoking exposure in asthmatics with IRAO.

METHODS

We studied asthmatics with IRAO who were further classified according to their smoking history, those with ≥20 pack-years of tobacco exposure (asthmatics with smoking-related IRAO [AwS-IRAO]) and those with <5 pack-years of tobacco exposure (asthmatics with nonsmoking-related IRAO [AwNS-IRAO]). In addition to recording baseline clinical and lung function features, all patients had a chest computed tomography (CT) from which airway wall thickness was measured and quantitative and qualitative assessment of emphysema was performed. The airway inflammatory profile was documented from differential inflammatory cell counts on induced sputum.

RESULTS

Ninety patients were recruited (57 AwS-IRAO and 33 AwNS-IRAO). There were no statistically significant differences in the extent of emphysema and gas trapping between groups on quantitative chest CT analysis, although Pi10, a marker of airway wall thickness, was significantly higher in AwS-IRAO (p = 0.0242). Visual analysis showed a higher prevalence of emphysema (p = 0.0001) and higher emphysema score (p < 0.0001) in AwS-IRAO compared to AwNS-IRAO and distribution of emphysema was different between groups. Correlations between radiological features and lung function were stronger in AwS-IRAO. In a subgroup analysis, we found a correlation between airway neutrophilia and emphysematous features in AwS-IRAO and between eosinophilia and both airway wall thickness and emphysematous changes in AwNS-IRAO.

CONCLUSIONS

Although bronchial structural changes were relatively similar in smoking and nonsmoking patients with asthma and IRAO, emphysematous changes were more predominant in smokers. However, neutrophils in AwS-IRAO and eosinophils in AwNS-IRAO were associated with lung and airway structural changes.

Pharmacology and Therapeutics of Bronchodilators Revisited

Bronchodilators remain the cornerstone of the treatment of airway disorders such as asthma and chronic obstructive pulmonary disease (COPD). There is therefore considerable interest in understanding how to optimize the use of our existing classes of bronchodilator and in identifying novel classes of bronchodilator drugs. However, new classes of bronchodilator have proved challenging to develop because many of these have no better efficacy than existing classes of bronchodilator and often have unacceptable safety profiles. Recent research has shown that optimization of bronchodilation occurs when both arms of the autonomic nervous system are affected through antagonism of muscarinic receptors to reduce the influence of parasympathetic innervation of the lung and through stimulation of β ₂-adrenoceptors (β ₂-ARs) on airway smooth muscle with β ₂-AR-selective agonists to mimic the sympathetic influence on the lung. This is currently achieved by use of fixed-dose combinations of inhaled long-acting β ₂-adrenoceptor agonists (LABAs) and long-acting muscarinic acetylcholine receptor antagonists (LAMAs). Due to the distinct mechanisms of action of LAMAs and LABAs, the additive/synergistic effects of using these drug classes together has been extensively investigated. More recently, so-called "triple inhalers" containing fixed-dose combinations of both classes of bronchodilator (dual bronchodilation) and an inhaled corticosteroid in the same inhaler have been developed. Furthermore, a number of so-called "bifunctional drugs" having two different primary pharmacological actions in the same molecule are under development. This review discusses recent advancements in knowledge on bronchodilators and bifunctional drugs for the treatment of asthma and COPD. SIGNIFICANCE STATEMENT: Since our last review in 2012, there has been considerable research to identify novel classes of bronchodilator drugs, to further understand how to optimize the use of the existing classes of bronchodilator, and to better understand the role of bifunctional drugs in the treatment of asthma and chronic obstructive pulmonary disease.

Effect of Pulmonary Rehabilitation in Patients with Asthma COPD Overlap Syndrome: A Randomized Control Trial

Objectives

We sought to evaluate the effectiveness of six weeks pulmonary rehabilitation (PR) in patients with asthma-chronic obstructive pulmonary disease (COPD) overlap syndrome (ACOS).

Methods

We enrolled 28 patients with ACOS. Fourteen patients were randomly allocated to the PR group, which comprised of supervised endurance training, supervised resistance training, breathing exercises, self management, and education. The other 14 patients were allocated to the control group, who were asked to continue their usual routine strategies for six weeks. All patients were assessed at baseline and after six weeks using the six minute walk test (6MWT), St George Respiratory Questionnaire (SGRQ), pulmonary function test (PFT), and Bode index (BI).

Results

We saw a significant improvement in 6MWT (p = 0.001), SGRQ (p = 0.007), and BI (p < 0.001) in the PR group after six weeks compared to the control group. There was no significant difference between the groups for PFT (p = 0.182) after six weeks.

Conclusions

Use of a short-term PR program in ACOS patients results in favorable changes in functional capacity, health-related quality of life, and BI. However, short-term PR was not sufficient to register changes in pulmonary function in these patients.

Evaluation of fluticasone propionate/salmeterol for the treatment of COPD: a systematic review

Introduction: Recently, the generic formulation of FP/SAL FDC has been approved in COPD. Although FP/SAL FDC has been the first long-acting FDC approved in COPD, no systematic review assessed the effect of this combination for the treatment of COPD by considering specifically Phase IV studies. The aim of this review was to systematically assess the effect of FP/SAL FDC in COPD patients enrolled in Phase IV studies.Areas covered: The question of this systematic review was to examine the evidence regarding the impact of FP/SAL FDC for the treatment of COPD by searching for Phase IV studies in the ClinicalTrials.gov database.Expert opinion: Generic drugs represent an effective cost-saving step for health-care budgets in the treatment of COPD and should be used in agreement with current recommendations and prescription accuracy. FP/SAL FDC is recommended for the initiation therapy just in a small percentage of symptomatic patients that are at high risk of exacerbation with blood eosinophil counts ≥300 cells per μl. At follow-up, FP/SAL FDC can be escalated to triple ICS/LABA/LAMA combination or switched to LABA/LAMA combination by considering symptoms, exacerbations, lack of response to ICS, inappropriate original indication, and ICS-related adverse events such as pneumonia.

Asthma-COPD Overlap and Chronic Airflow Obstruction: Definitions, Management, and Unanswered Questions

Asthma-chronic obstructive pulmonary disease (COPD) overlap (ACO) is a common clinical presentation of chronic airways disease in which patients show some features usually associated with asthma, and some usually associated with COPD. There is ongoing debate over whether ACO is a discrete clinical entity, or if it is part of a continuum of airways disease. Furthermore, there is considerable variation among current definitions of ACO, which makes diagnosis potentially challenging for clinicians. Treating ACO may be equally challenging because ACO is an understudied population, and the evidence base for its management comes largely from asthma and COPD studies, the relevance of which deserves careful consideration. In this review, we synthesize the various approaches to ACO diagnosis and evaluate the role of currently available diagnostic tests. We describe the potential benefits of existing asthma and COPD therapies in treating patients with ACO, and the value of a "treatable traits" approach to ACO management. Throughout the review, we highlight some of the pressing, unanswered questions surrounding ACO that are relevant to the clinical community. Ultimately, addressing these questions is necessary if we are to improve clinical outcomes for this complex and heterogeneous patient population.

Triple Therapy Versus Dual Bronchodilation and Inhaled Corticosteroids/Long-Acting β-Agonists in COPD: Accumulating Evidence from Network Meta-Analyses

Guidelines are mainly based on evidence of well-designed randomized controlled trials (RCTs), but there are limitations to the transferability of conclusions of RCTs to usual care mainly because the patients enrolled in RCTs are selected and not representative of the population encountered in daily practice; moreover, the research environment is substantially different from that of the real world. Because of the scarcity of data generated in large unselected populations in everyday clinical practice, the possibility of using meta-analyses can be considered. Recently, several meta-analyses have attempted to clarify the role of triple therapy containing a long-acting β-agonist (LABA), a long-acting muscarinic antagonist (LAMA) and an inhaled corticosteroid (ICS) delivered from a single inhaler in chronic obstructive pulmonary disease (COPD), also considering that there is a big difference in the use of triple therapy between what is recommended by COPD guidelines or strategies and the prescriptive behaviour of clinicians. Taking into account the results of the most recent meta-analyses, we believe that triple therapy provides modest clinical benefit in the general COPD population, but in patients on LABA/LAMA combination therapy, who still experience acute exacerbations of COPD (AECOPDs) and have blood eosinophil counts ≥ 300 cells·μl⁻¹, it is of clinical relevance. On the contrary, adding a LAMA to an ICS/LABA combination elicits relevant clinical benefit in the general COPD population, supporting the role of dual bronchodilation therapy for the treatment of COPD. The quantitative synthesis of the currently available clinical evidence seems to suggest that, in patients with COPD already on ICS/LABA combination, the therapy can be improved without an increase of cardiovascular severe adverse events (SAEs) when a LAMA is added to the combination.

A potential role of triple therapy for asthma patients

Introduction: The use of LAMAs in asthma is now supported by pharmacological and clinical evidence, whereas the effectiveness of therapy with ICS/LABA/LAMA fixed dose combinations in patients with asthma still remains to be determined. Areas covered: The pharmacological rationale that explains why it is possible to use triple therapy in asthma and the results of clinical studies that have explored the effects of this therapy in asthmatics is critically examined. A systematic search was conducted on 10 August 2019, and included six electronic databases: EMBASE, MEDLINE, Scopus, The Cochrane Library, Web of Science, and Google Scholar. Expert opinion: The real role of single inhaler triple therapy in asthma will be demonstrated when the various trials that are currently ongoing or are scheduled will be completed. We believe that it is appropriate to treat with triple therapy asthmatic patients who have smoked and remain symptomatic or suffer from frequent exacerbations despite initial inhaler therapy with ICS/LABA. However, we must establish when to step up or mainly step down triple therapy especially in patients who are well controlled, and what will be the cost of these combinations in the management of asthma.

Controversies in Allergy: Is Asthma Chronic Obstructive Pulmonary Disease Overlap a Distinct Syndrome That Changes Treatment and Patient Outcomes?

While asthma/COPD overlap (ACO), like both asthma and COPD alone, is not a distinct syndrome, nonetheless it does have features that distinguish it from asthma and COPD only. Similar to the latter obstructive pulmonary disorders, it most likely represents a complex spectrum of diseases comprising several different phenotypes and underlying pathophysiologies. It also not yet clear how ACO is best defined, i.e., by clinical features (age, physiology, bronchodilator responsiveness, symptom variability, history of asthma), biomarkers or a combination of these features. The lack of generally agreed-on diagnostic criteria probably accounts for the marked heterogeneity of the results of published surveys of its prevalence. Until a true consensus is achieved regarding the definition of ACO, it will not be possible to determine with confidence not only its prevalence, but also its natural history (outcomes), its underlying biology or its optimal treatment based on findings from randomized controlled clinical trials focused specifically on patients with well-defined ACO.

Decreased serum club cell secretory protein in asthma and chronic obstructive pulmonary disease overlap: a pilot study

Purpose

Improvement in the diagnosis of asthma and chronic obstructive pulmonary disease (COPD) overlap (ACO), and identification of biomarkers for phenotype recognition will encourage good patient care by providing optimal therapy. We investigated club cell secretory protein (CC-16), a protective and anti-inflammatory mediator, as a new candidate biomarker for diagnosing ACO.

Patients and methods

We performed a multicenter cohort study. A total of 107 patients were divided into three groups - asthma, COPD, and ACO - according to the Spanish guidelines algorithm, and enrolled into the study. Serum CC-16 levels were measured using commercial ELISA kits.

Results

Serum CC-16 levels were the lowest in patients with ACO. Low serum CC-16 levels were a significant marker for the ACO even after adjustment for age, sex, and smoking intensity. Serum CC-16 levels were positively correlated with forced expiratory volume in 1 second (FEV₁), forced vital capacity (FVC), forced expiratory flow at 25%-75% of FVC, FEV₁/FVC, vital capacity, and diffusing capacity of the lung for carbon monoxide, and were negatively correlated with smoking amount (pack-years), bronchodilator response, fractional residual capacity, residual volume, and number of exacerbations per year. FEV₁ and serum CC-16 levels were significantly lower in patients with frequent exacerbations.

Conclusion

Serum CC-16 has the potential to be a biomarker for ACO diagnosis and also treat frequent exacerbations in patients with chronic inflammatory airway diseases.

Precision medicine in COPD: where are we and where do we need to go?

Chronic obstructive pulmonary disease (COPD) was the fourth leading cause of death worldwide in 2015. Current treatments for patients ease discomfort and help decrease disease progression; however, none improve lung function or change mortality. COPD is heterogeneous in its molecular and clinical presentation, making it difficult to understand disease aetiology and define robust therapeutic strategies. Given the complexity of the disease we propose a precision medicine approach to understanding and better treating COPD. It is possible that multiOMICs can be used as a tool to integrate data from multiple fields. Moreover, analysis of electronic medical records could aid in the treatment of patients and in the predictions of outcomes. The Precision Medicine Initiative created in 2015 has made precision medicine approaches to treat disease a reality; one of these diseases being COPD.

Increased urinary l-histidine in patients with asthma-COPD overlap: a pilot study

Purpose

Asthma-COPD overlap (ACO) is heterogeneous in nature and requires a unified diagnostic approach. We investigated the urinary levels of l-histidine, a precursor of histamine related to inflammatory responses, as a new candidate biomarker for diagnosing this condition.

Patients and methods

We performed a prospective multicenter cohort study with retrospective analysis of 107 patients, who were divided into three groups: asthma, COPD, and ACO, according to the Spanish guidelines algorithm. Urinary l-histidine levels were measured using liquid chromatography-mass spectrometry. High-resolution metabolomic analysis, coupled with liquid chromatography-mass spectrometry and followed by multivariate statistical analysis, was performed on urine samples to discriminate between the metabolic profiles of the groups.

Results

Urinary l-histidine levels were significantly higher in patients with ACO than in those with asthma or COPD, but the subgroups of ACO, classified according to disease origin, did not differ significantly. High urinary l-histidine level was a significant factor for the diagnosis of ACO even after adjusting for age, sex, and smoking amount. Among patients with airflow obstruction, the urinary l-histidine levels were elevated in patients with a documented history of asthma before the age of 40 years or bronchodilator responsiveness ≥400 mL; bronchodilator responsiveness ≥200 mL of forced expiratory volume in 1 second and exceeding baseline values by 12% on two or more visits; blood eosinophil count ≥300 cells·mm^-3; and frequent exacerbations (P < 0.05).

Conclusion

Urinary l-histidine could be a potential biomarker for ACO, regardless of the diversity of diagnostic definitions used.

Chronic obstructive pulmonary disease subpopulations and phenotyping

The diagnosis and treatment of chronic obstructive pulmonary disease (COPD) has been based largely on a one-size-fits-all approach. Diagnosis of COPD is based on meeting the physiologic criteria of fixed obstruction in forced expiratory flows and treatment focus on symptomatic relief, with limited effect on overall prognosis. However, patients with COPD have distinct features that determine very different evolutions of the disease. In this review we highlight distinct subgroups of COPD characterized by unique pathophysiologic derangements, response to treatment, and disease progression. It is likely that identification of subgroups of COPD will lead to discovery of much needed disease-modifying therapeutic approaches. We argue that a precision approach that integrates multiple dimensions (clinical, physiologic, imaging, and endotyping) is needed to move the field forward in the treatment of this disease.

Asthma-COPD Overlap Phenotypes and Smoking :Comparative features of asthma in smoking or non-smoking patients with an incomplete reversibility of airway obstruction

The development of COPD features, such as an incomplete reversibility of airway obstruction (IRAO), in smoking or non-smoking asthmatic patients, a condition often named Asthma-COPD Overlap (ACO), has been recognized for decades. However, there is a need to know more about the sub-phenotypes of this condition according to smoking. This study aimed at comparing the clinical, physiological and inflammatory features of smoking and non-smoking asthmatic patients exhibiting IRAO. In this cross-sectional study, patients with an IRAO with (ACO, ≥20 pack-years) or without (NS-IRAO, <5 pack-years) significant smoking history completed questionnaires about asthma control (ACQ, score 0-6, 6 = better score) and quality of life (AQLQ, score 1-7, 1 = better score) and performed expiratory flows, lung volume and carbon monoxide diffusion capacity measurements. Blood sampling and induced sputum were obtained for systemic and lower airway inflammation assessment. A total of 115 asthmatic patients were included (75 ACO: age 61 ± 10 years, 60% women and 40 NS-IRAO: age 64 ± 9 years, 38% women). ACO patients had worse asthma control scores (1.8 ± 0.9 vs 1.4 ± 0.9, P = 0.02) and poorer asthma quality of life (5.3 ± 1.0 vs 5.9 ± 1.0, P = 0.003). In addition, ACO had higher residual volume (145 ± 45 vs 121 ± 29% predicted, P = 0.008) and a lower carbon monoxide diffusing capacity corrected for alveolar volume (90 ± 22 vs 108 ± 20% predicted, P = 0.0008). No significant differences were observed in systemic or lower airway inflammation. In conclusion, in smokers and non-smokers, the presence of IRAO in asthmatics is associated with different phenotypes that reflect the addition of smoking-induced changes to asthma physiopathology.

Heterogeneity of asthma and COPD overlap

Background

Asthma and COPD are heterogeneous diseases. Patients with both disease features (asthma-COPD overlap [ACO]) are common. However, clinical characteristics and socio-economic burden of ACO are still controversial. The aim of this study was to identify the heterogeneity of ACO and to find out the subtypes with clinical impact among ACO subtypes.

Methods

In the Korean National Health and Nutrition Examination Survey (KNHANES) conducted between 2007 and 2012, subjects who were ≥40 years and had prebronchodilator FEV₁/FVC <0.7 and FEV₁ ≥50% predicted were included. The presence or absence of self-reported wheezing was indicated by W+ or W- and used as an index of airway hyper-responsiveness. S+/S- was defined as subjects who were smokers/never smokers. The subjects were divided into the following four groups: W-S-, W-S+, W+S-, and W+S+. W+S- and W+S+ were asthma-predominant ACO and COPD-predominant ACO, respectively. KNHANES and linked National Health Insurance data were analyzed.

Results

The asthma-predominant ACO group showed the lowest socioeconomic status, FEV₁, FVC% predicted, and quality of life (QoL) levels. The COPD-predominant ACO group showed the highest hospitalization rate, outpatient medical cost, and total and outpatient health care utilization. COPD-predominant ACO was associated with exacerbations compared to the W-S- group (adjusted odds ratio [aOR], 1.79; 95% confidence interval [CI], 1.12-2.85; P=0.015) and W-S+ group (OR 2.11; 95% CI 1.43-3.10; P<0.001). COPD-predominant ACO was associated with increased medical cost.

Conclusion

Asthma-predominant ACO individuals displayed poorer socioeconomic status and QoL compared to the COPD-predominant ACO group. The COPD-predominant ACO group displayed more frequent exacerbations and greater medical costs. Considering the heterogeneity of ACO, it is desirable to identify subtypes of ACO patients and appropriately allocate limited medical resources.

Beclomethasone dipropionate and formoterol fumarate synergistically interact in hyperresponsive medium bronchi and small airways

Background

Corticosteroids increase the expression of β₂-adrenoceptors (β₂-ARs) and protect them against down-regulation. Conversely, β₂-AR agonists improve the anti-inflammatory action of corticosteroids. Nevertheless, it is still uncertain whether adding a long-acting β₂-AR agonist (LABA) to an inhaled corticosteroid (ICS) results in an additive effect, or there is true synergy.

Therefore, the aim of this study was to pharmacologically characterize the interaction between the ICS beclomethasone diproprionate (BDP) and the LABA formoterol fumarate (FF) in a validated human ex vivo model of bronchial asthma.

Methods

Human medium and small airways were stimulated by histamine and treated with different concentrations of BDP and FF, administered alone and in combination at concentration-ratio reproducing ex vivo that of the currently available fixed-dose combination (FDC; BDP/FF 100:6 combination-ratio). Experiments were performed in non-sensitized (NS) and passively sensitized (PS) airways. The pharmacological interaction was assessed by using Bliss Independence and Unified Theory equations.

Results

BDP/FF synergistically increased the overall bronchorelaxation in NS and PS airways (+ 15.15% ± 4.02%; P < 0.05 vs. additive effect). At low-to-medium concentrations the synergistic interaction was greater in PS than in NS bronchioles (+ 16.68% ± 3.02% and + 7.27% ± 3.05%, respectively). In PS small airways a very strong synergistic interaction (Combination Index: 0.08; + 20.04% ± 2.18% vs. additive effect) was detected for the total concentrations of BDP/FF combination corresponding to 10.6 ng/ml.

Conclusion

BDP/FF combination synergistically relaxed human bronchi; the extent of such an interaction was very strong at low-to-medium concentrations in PS small airways.

Trial registration

Not applicable.

Electronic supplementary material

The online version of this article (10.1186/s12931-018-0770-7) contains supplementary material, which is available to authorized users.

The Challenges of Precision Medicine in COPD

Pheno-/endotyping chronic obstructive pulmonary disease (COPD) is really important because it provides patients with precise and personalized medicine. The central concept of precision medicine is to take individual variability into account when making management decisions. Precision medicine should ensure that patients get the right treatment at the right dose at the right time, with minimum harmful consequences and maximum efficacy. Ideally, we should search for genetic and molecular biomarker-based profiles. Given the clinical complexity of COPD, it seems likely that a panel of several biomarkers will be required to characterize pathogenetic factors and their course over time. The need for biomarkers to guide the clinical care of individuals with COPD and to enhance the possibilities of success in drug development is clear and urgent, but biomarker development is tremendously challenging and expensive, and translation of research efforts to date has been largely ineffective. Furthermore, the development of personalized treatments will require a much more detailed understanding of the clinical and biological heterogeneity of COPD. Therefore, we are still far from being able to apply precision medicine in COPD and the treatable traits and FEV₁-free approaches are attempts to precision medicine in COPD that must be considered still quite unsophisticated.

Plasma YKL-40 and NGAL are useful in distinguishing ACO from asthma and COPD

BACKGROUND

Asthma-chronic obstructive pulmonary disorder (COPD) overlap (ACO) is characterized by the coexistence of features of both asthma and COPD and is associated with rapid progress and a poor prognosis. Thus, the early recognition of ACO is crucial.

OBJECTIVES

We sought to explore the plasma levels of biomarkers associated with asthma (periostin, TSLP and YKL-40), COPD (NGAL) and their possible correlation with lung function, the bronchodilator response and radiographic imaging in patients with asthma, COPD and with features of ACO.

METHODS

We enrolled 423 subjects from 6 clinical centers. All participants underwent blood collection, lung function measurements, bronchodilator response tests and high-resolution CT. Correlations of the plasma biomarkers with lung function, the bronchodilator response and percentemphysema were calculated by Spearman's rank correlation and multivariate stepwise regressionanalysis.

RESULTS

1) Patients with features of ACO had lower plasma YKL-40 than COPD patients and a moderate elevated plasma level of NGAL compared with asthma patients. 2) Patients with features of ACO had an intermediate degree of airflow obstruction, the bronchodilator response and emphysema between patients with COPD and asthma. 3) Plasma YKL-40 was negatively correlated with lung function and with the bronchodilator response, and plasma NGAL was positively correlated with the extent of emphysema.

CONCLUSIONS

Plasma YKL-40 is a promising candidate for distinguishing between patients with features of ACO and COPD patients, while plasma NGAL may be a valuable biomarker for differentiating between patients with features of ACO and asthma patients.

CLINICAL TRIAL REGISTRATION

ChiCTR-OOC-16009221.

Use of clinical characteristics to predict spirometric classification of obstructive lung disease

Background

There is no consensus on how to define patients with symptoms of asthma and chronic obstructive pulmonary disease (COPD). A diagnosis of asthma–COPD overlap (ACO) syndrome has been proposed, but its value is debated. This study (GSK Study 201703 [NCT02302417]) investigated the ability of statistical modeling approaches to define distinct disease groups in patients with obstructive lung disease (OLD) using medical history and spirometric data.

Methods

Patients aged ≥18 years with diagnoses of asthma and/or COPD were categorized into three groups: 1) asthma (nonobstructive; reversible), 2) ACO (obstructive; reversible), and 3) COPD (obstructive; nonreversible). Obstruction was defined as a post-bronchodilator forced expiratory volume in 1 second (FEV₁)/forced vital capacity <0.7, and reversibility as a post-albuterol increase in FEV₁ ≥200 mL and ≥12%. A primary model (PM), based on patients’ responses to a health care practitioner-administered questionnaire, was developed using multinomial logistic regression modeling. Other multivariate statistical analysis models for identifying asthma and COPD as distinct entities were developed and assessed using receiver operating characteristic (ROC) analysis. Partial least squares discriminant analysis (PLS-DA) assessed the degree of overlap between groups.

Results

The PM predicted spirometric classifications with modest sensitivity. Other analysis models performed with high discrimination (area under the ROC curve: asthma model, 0.94; COPD model, 0.87). PLS-DA identified distinct phenotypic groups corresponding to asthma and COPD.

Conclusion

Within the OLD spectrum, patients with asthma or COPD can be identified as two distinct groups with a high degree of precision. Patients outside these classifications do not constitute a homogeneous group.

Prevalence and features of asthma-chronic obstructive pulmonary disease overlap in Northern Italy general population

OBJECTIVE

There is controversy about the diagnostic criteria, prevalence, symptoms, and spirometry characteristics of asthma-chronic obstructive pulmonary disease (COPD) overlap (ACO). Recent data indicate that the fixed method for diagnosing airway obstruction (AO) may overestimate ACO prevalence in the elderly, and a variable method may be more accurate. We aimed at estimating ACO prevalence in a general population sample and comparing patient and clinical features in subjects with ACO, COPD, and asthma.

METHODS

We analyzed data from a cross-sectional study estimating COPD prevalence in randomly selected adults aged 20-79 years in Verona, Italy, and estimated prevalence and analyzed characteristics of asthma, COPD, and ACO. ACO was defined as AO (Forced Expiratory Volume in one second-FEV₁/ Forced Vital Capacity-FVC < Lower Limit of Normal-LLN), highly positive bronchodilator test (≥15% increase in FEV₁ and FVC ≥400 mL), and personal self-reported history of physician diagnosed asthma and atopy.

RESULTS

One thousand two hundred and thirty-six patients were included; 207 (16.7%) had asthma, COPD, or ACO (mean ages: 61.2, 59.7, and 57.2 years, respectively). The 3 groups had similar clinical and demographic variables; however, spirometry revealed differences between ACO and COPD patients, particularly post-bronchodilator FEV₁ reversibility, which was detected in ACO and asthma patients but not in those with COPD.

CONCLUSION

ACO prevalence in Northern Italy was estimated at 2.1%, in the range of values reported by previous studies. Marked differences between ACO and COPD revealed by spirometry may have important clinical implications in terms of treatment for patients with ACO.

Perceptions of Severe Asthma and Asthma-COPD Overlap Syndrome Among Specialists: A Questionnaire Survey

Purpose

Severe asthma and asthma-chronic obstructive pulmonary disease (COPD) overlap syndrome (ACOS) are difficult to control and are often associated with poor clinical outcomes. However, much is not understood regarding the diagnosis and treatment of severe asthma and ACOS. To evaluate the current perceptions of severe asthma and COPD among asthma and COPD specialists, we designed an e-mail and internet-based questionnaire survey.

Methods

Subjects were selected based on clinical specialty from among the members of the Korean Academy of Asthma, Allergy and Clinical Immunology and the Korean Academy of Tuberculosis and Respiratory Diseases. Of 432 subjects who received an e-mail invitation to the survey, 95 subjects, including 58 allergists and 37 pulmonologists, responded and submitted their answers online.

Results

The specialists estimated that the percentage of severe cases among total asthma patients in their practice was 13.9%±11.0%. Asthma aggravation by stepping down treatment was the most common subtype, followed by frequent exacerbation, uncontrolled asthma despite higher treatment steps, and serious exacerbation. ACOS was estimated to account for 20.7% of asthma, 38.0% of severe asthma, and 30.1% of COPD cases. A history of smoking, persistently low forced expiratory volume in 1 second (FEV1), and low FEV1 variation were most frequently classified as the major criteria for the diagnosis of ACOS among asthma patients. Among COPD patients, the highly selected major criteria for ACOS were high FEV1 variation, positive bronchodilator response, a personal history of allergies and positive airway hyperresponsiveness. Allergists and pulmonologists showed different assessments and opinions on asthma phenotyping, percentage, and diagnostic criteria for ACOS.

Conclusions

Specialists had diverse perceptions and clinical practices regarding severe asthma and ACOS patients. This heterogeneity must be considered in future studies and strategy development for severe asthma and ACOS.

Asthma-chronic obstructive pulmonary disease overlap syndrome: a controversial concept

PURPOSE OF REVIEW

To illustrate the scant evidence and the shortcomings of the concept of 'asthma-COPD overlap syndrome' (ACOS) in terms of clinical utility.

RECENT FINDINGS

Asthma and chronic obstructive pulmonary disease (COPD) are considered as two distinct and heterogeneous diseases. For many years, physicians have been aware that asthma and COPD can coexist in some patients. Recently, the term ACOS has been applied when a person has clinical features of both asthma and COPD. However, the lack of an accurate diagnosis has led to inconsistent data regarding reported prevalence, prognosis and therapeutics. Even today, it has not been possible to establish a phenotypic characterization of ACOS, although it is part of the overall complexity and heterogeneity of COPDs. No high quality data exist on which to base treatment recommendations for ACOS. Consequently, in clinical practice, treatment is extrapolated from the available evidence on asthma and COPD.

SUMMARY

The current concept of ACOS seems clinically irrelevant because it has no influence on the prognosis and treatment of these patients. The authors concluded that the term ACOS should be avoided in the case of patients with features of both asthma and COPD.

Pharmacological characterization of the interaction between tiotropium and olodaterol administered at 5:5 concentration-ratio in equine bronchi

Equine airways represent a suitable ex vivo model to study the functional impact of pharmacological treatments on human chronic obstructive pulmonary disorders, such as asthma and chronic obstructive pulmonary disease (COPD). We aimed to characterize the pharmacological interaction between the long-acting muscarinic antagonist (LAMA) tiotropium and the long-acting β₂-agonist (LABA) olodaterol in equine airways. The effect of tiotropium and olodaterol, administered alone and in combination at the ratio of concentrations reproducing ex vivo the concentration-ratio delivered by the currently available fixed-dose combination (FDC) (5:5), was investigated on the cholinergic contractile tone induced by the parasympathetic activation of equine isolated airways. The drug interaction was analysed by using the Bliss Independence and Unified Theory models. Both tiotropium and olodaterol induced a sub-maximal concentration-dependent inhibition of bronchial contractility (E_max: tiotropium 83.6 ± 14.8%, olodaterol 76.9 ± 17.9%; pEC₅₀: tiotropium 8.2 ± 0.5; olodaterol 8.3 ± 0.6). When administered at 5:5 concentration-ratio, tiotropium plus olodaterol completely inhibited the bronchial contractility (E_max 102.7 ± 8.4%; pEC₅₀ 9.0 ± 0.7). Strong synergistic interaction was detected for tiotropium/olodaterol combination (combination index 0.011). When administered at low concentrations, the drug mixture elicited up to 94.6 ± 9.5% effect that was 36.0 ± 8.1% greater than the expected additive effect. The results of this study demonstrate that the co-administration of tiotropium plus olodaterol at 5:5 concentration-ratio leads to synergistic inhibition of equine bronchial contractility when compared with either drug administered alone. These findings suggest that the currently available LABA/LABA FDC may be effective in delivering tiotropium/olodaterol combination at equipotency concentrations of each monocomponent into the lung and, thus, inducing synergistic effect in the airways.

Different prevalence and clinical characteristics of asthma-chronic obstructive pulmonary disease overlap syndrome according to accepted criteria

BACKGROUND

A unified definition of asthma-chronic obstructive pulmonary disease overlap syndrome (ACOS) is not available, which makes it difficult to evaluate the prevalence and clinical features of patients with ACOS.

OBJECTIVE

To investigate the prevalence and clinical characteristics of ACOS according to the updated widely accepted diagnostic criteria.

METHODS

Participants were enrolled from a prospective cohort study conducted between April 2013 and November 2016 in South Korea. We adopted 4 criteria of ACOS: modified Spanish, American Thoracic Society (ATS) Roundtable criteria, the Latin American Project for the Investigation of Obstructive Lung Disease (PLATINO), and the Global Initiative for Asthma/Global Initiative for Chronic Obstructive Lung Disease (GINA/GOLD) criteria. The prevalence, clinical characteristics, and exacerbations of ACOS were investigated.

RESULTS

Among 301 patients with chronic obstructive pulmonary disease, 31.3%, 11.9%, 48.3%, and 46.15% were diagnosed with ACOS according to the modified Spanish, ATS Roundtable criteria, PLATINO, and GINA/GOLD criteria, respectively. Compared with other criteria, patients with ACOS diagnosed according to the modified Spanish criteria had better exercise capacity and lung function at baseline but higher risk of moderate to severe (adjusted hazard ratio, 1.97; 95% confidence interval, 1.14-3.41; P = .01) and total (adjusted odds ratio, 2.10; 95% confidence interval, 1.33-3.31; P < .01) exacerbations during at least a 1-year follow-up period than patients without ACOS.

CONCLUSION

The prevalence of ACOS varied according to the diagnostic criteria. Among the different criteria, the modified Spanish criteria could identify patients with more asthmatic features and higher risk of exacerbation.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT02527486.

Management of the Asthma-COPD Overlap Syndrome (ACOS): a Review of the Evidence

PURPOSE OF REVIEW

Examine the definition of the asthma-COPD overlap syndrome (ACOS) and current treatment strategies.

RECENT FINDINGS

Patients with the ACOS have a lower quality of life and suffer from more complications than those affected by either disease alone. Diagnosis of ACOS is difficult because of the clinical similarities between the two diseases and the various phenotypes that comprise the syndrome. Defining treatment strategies for ACOS has been challenging because many clinical trials for asthma therapy have purposefully excluded patients with features of COPD, and COPD clinical trials have not included patients who might have an asthmatic component to their disease. Therefore, there are few randomized treatment trials which have included patients who have ACOS. Smoking cessation and appropriate vaccinations are cornerstone therapies, and pharmacologic therapy has focused on bronchodilators and inhaled corticosteroids. The role of biologics, such as omalizumab and IL-5 antagonists, in ACOS treatment is still being defined. As of now, with the paucity of randomized control trials guiding treatment strategies, the Global Initiative for Asthma (GINA) and Global Initiative for Chronic Obstructive Lung Disease (GOLD) guidelines recommend treating ACOS according to the dominant phenotype.

Prevalence and characteristics of asthma-COPD overlap syndrome identified by a stepwise approach

BACKGROUND AND OBJECTIVE

There is increasing recognition of asthma-COPD overlap syndrome (ACOS), which shares some features of both asthma and COPD; however, the prevalence and characteristics of ACOS are not well understood. The aim of this study was to investigate the prevalence of ACOS among patients with COPD and its characteristics using a stepwise approach as stated in the recent report of the Global Initiative for Asthma (GINA) and the Global Initiative for Chronic Obstructive Lung Disease (GOLD).

METHODS

This multicenter, cross-sectional, observational study enrolled outpatients who were receiving medical treatment for COPD. Clinical data, including spirometry results, were retrieved from medical records. For symptom assessment, patients were asked to complete the Clinical COPD questionnaire and the modified British Medical Research Council questionnaire.

RESULTS

Of the 1,008 patients analyzed, 167 (16.6%) had syndromic features of ACOS. Of the total number of patients, 93 and 42 (9.2% and 4.2%) also had a predefined clinical variability of ≥12%/≥200 mL and ≥12%/≥400 mL in forced expiratory volume in 1 second (FEV1), respectively, and therefore were identified as having ACOS. Conversely, the number of patients who had either syndromic or spirometric feature of ACOS was 595 (59.0%, ≥12%/≥200 mL FEV1 clinical variability), and 328 patients (32.5%, ≥12%/≥400 mL FEV1 clinical variability) had both the features. Patients identified as having ACOS were of significantly younger age, had a shorter duration of COPD, lower number of pack-years, better lung function, milder dyspnea symptoms, and higher peripheral blood eosinophil values compared with patients with COPD alone. The rate of exacerbations in the previous year was not significantly different between the ACOS and COPD groups.

CONCLUSION

Using a stepwise approach, as stated in the GINA/GOLD report, the proportions of patients identified as having ACOS were found to be 9.2% and 4.2% (depending on the FEV1 variability cutoff used) among the 1,008 outpatients medically treated for COPD in a real-life clinical setting.

Defining asthma-COPD overlap syndrome: a population-based study

Asthma-chronic obstructive pulmonary disease (COPD) overlap syndrome (ACOS) seems an important clinical phenotype, but multiple definitions have been proposed. This study's objectives were to assess the effect of different ACOS definitions on prevalence, patient characteristics and exacerbations.5675 individuals aged 45-65 years, with 846 asthma/COPD patients, were included in the Netherlands Epidemiology of Obesity study between 2008 and 2012, and followed-up for a median of 1.8 years. ACOS was defined by recent consensus criteria and five other definitions, based on registry, questionnaires and lung function.Prevalence of ACOS in the asthma/COPD population ranged between 4.4% and 38.3%, depending on the definition used. Agreement between registry-based and self-reported ACOS was 0.04 and 0.41 when lung function (forced expiratory volume in 1 s (FEV₁)/forced vital capacity (FVC) <0.7) was added. With registry or self-report defined ACOS, only 51% and 33% had FEV₁/FVC <0.7. Patient characteristics were similar, but asthma duration was longer with self-reported compared with registry-based ACOS (mean difference 22 years (95% CI 12-33)). Exacerbation risk was highest with registry-based ACOS compared with asthma (adjusted incidence rate ratio 1.6 (95% CI 1.2-2.1)).This study adds important knowledge about agreement between ACOS definitions and their relation with exacerbations. Given the low agreement, differences in prevalence, patient characteristics and risk of exacerbations, consensus about ACOS definition in different care settings is urgently needed.

Asthma and smoking-induced airway disease without spirometric COPD

Due to the high prevalence rates of cigarette smoking and asthma, current and ex-smokers frequently develop chronic airway disease without spirometric evidence of chronic obstructive pulmonary disease (COPD), either alone or associated with asthma. This review considers the classification, clinical outcomes, inflammatory and imaging variables, phenotypes, and management of current and ex-smokers with airway disease without COPD, focusing on overlaps in those with and without asthma. These individuals have more respiratory symptoms, worse quality of life, increased exacerbation rates, reduced lung function and more comorbidities than never-smokers with asthma or healthy never-smokers. As well as clinical features, airway inflammatory and structural changes in smoking-induced airway disease without COPD overlap with those found in smokers with asthma. Cigarette smoking is associated with worse clinical outcomes in some phenotypes of asthma. Management involves public health measures to control exposure to tobacco smoke, personal advice on smoking cessation and the use of appropriate targeted therapies, although evidence is limited on their effectiveness. Understanding the mechanisms, natural history and management of current and ex-smokers with asthma and smoking-induced airway disease without COPD is a priority for future research.

Understanding COPD-overlap syndromes

INTRODUCTION

Chronic obstructive pulmonary disease accounts for a large burden of lung disease. It can 'overlap' with other respiratory diseases including bronchiectasis, fibrosis and obstructive sleep apnea (OSA). While COPD alone confers morbidity and mortality, common features with contrasting clinical outcomes can occur in COPD 'overlap syndromes'. Areas covered: Given the large degree of heterogeneity in COPD, individual variation to treatment is adopted based on its observed phenotype, which in turn overlaps with features of other respiratory disease states such as asthma. This is coined asthma-COPD overlap syndrome ('ACOS'). Other examples of such overlapping clinical states include bronchiectasis-COPD ('BCOS'), fibrosis-COPD ('FCOS') and OSA-COPD ('OCOS'). The objective of this review is to highlight similarities and differences between the COPD-overlap syndromes in terms of risk factors, pathophysiology, diagnosis and potential treatment differences. Expert commentary: As a consequence of COPD overlap syndromes, a transition from the traditional 'one size fits all' treatment approach is necessary. Greater treatment stratification according to clinical phenotype using a precision medicine approach is now required. In this light, it is important to recognize and differentiate COPD overlap syndromes as distinct disease states compared to individual diseases such as asthma, COPD, fibrosis or bronchiectasis.

Concurrent physician-diagnosed asthma and chronic obstructive pulmonary disease: A population study of prevalence, incidence and mortality

OBJECTIVE

We conducted a population-based cohort study to estimate trends in prevalence, incidence, and mortality of concurrent physician-diagnosed asthma and chronic obstructive pulmonary disease (COPD).

STUDY DESIGN AND SETTING

Two validated health administrative case definitions were used to identify asthma and COPD among all individuals aged 35 years and older living in Ontario, Canada. Annual asthma, COPD, and concurrent asthma and COPD prevalence, incidence, and mortality, standardized for age and sex, were estimated, and compared from 2002 to 2012, using generalized linear models.

RESULTS

Standardized prevalence of concurrent asthma and COPD increased by 10.5%, from 2.9% in 2002 to 3.2% in 2012 overall, but more prominently in women compared to men. Overall, standardized incidence decreased by16%, from 2.5 to 2.1 per 1000 individuals, but increased significantly in young adults. All-cause mortality among patients with concurrent asthma and COPD decreased by 11.2%, from 2.6% to 2.2%. Being diagnosed with both diseases was significantly associated with higher all-cause mortality compared to asthma (OR = 1.56, 95% CI: 1.50-1.58), but not compared to COPD (OR = 0.97, 0.96-0.98), except in young adults aged 35 to 49 years where people with asthma and COPD had higher mortality (OR = 1.21, 1.15-1.27).

CONCLUSIONS

In a large North American population, the burden of concurrent physician-diagnosed asthma and COPD is increasing, particularly in women and young adults.

Comparative prevalence of co-morbidities in smoking and non-smoking asthma patients with incomplete reversibility of airway obstruction, non-smoking asthma patients with complete reversibility of airway obstruction and COPD patients

BACKGROUND

Asthma with incomplete reversibility of airway obstruction (IRAO) may often be associated to smoking-induced changes. Nevertheless, a high proportion of patients showing IRAO have never smoked. These patients with IRAO often share features of patients with chronic obstructive pulmonary disease (COPD). Although IRAO is still a poorly defined condition, it has been associated with a higher morbidity and mortality than asthma with complete reversibility of airway obstruction (CRAO) or even COPD alone. A high prevalence of comorbidities could contribute to the reported poorer clinical outcome in IRAO, in comparison to CRAO or COPD alone.

AIM

To determine the prevalence of past and current comorbidities in IRAO patients compared to patients with CRAO or COPD.

METHODS

This was a retrospective, cross-sectional study. Demographic data, clinical characteristics and 36 predetermined comorbidities documented from self-report and chart review, were recorded from smoking-associated IRAO (S-IRAO), non-smoking IRAO (NS-IRAO), CRAO and COPD patients.

RESULTS

A total of 199 patients were included in the final analysis (111F/88M, mean (±SD) age of 63 ± 10 years). The CRAO group had more comorbidities than the three other groups, but this difference was significant only with the NS-IRAO group (P = 0.04). For most comorbidities, the prevalence of comorbidities in both IRAO sub-groups was intermediate between CRAO and COPD, with significant differences between S-IRAO and NS-IRAO only for hypertension (P = 0.03), nasal polyps (P = 0.002) and pneumonia (P = 0.04). Typical asthma-associated comorbidities tended to be more prevalent in NS-IRAO patients and COPD-associated comorbidities in S-IRAO patients.

CONCLUSION

In this study, the prevalence of comorbidities was not superior in patients with IRAO, compared to those with CRAO or COPD alone. The prevalence of comorbidities in the two main types of IRAO patients reflects exposure to cigarette smoke and asthma-related mechanisms.

Incidence and long-term outcome of severe asthma-COPD overlap compared to asthma and COPD alone: a 35-year prospective study of 57,053 middle-aged adults

Background

Incidence and prognosis for severe asthma–COPD overlap is poorly characterized. We investigated incidence and long-term outcome for patients with asthma–COPD overlap compared to asthma and COPD alone.

Materials and methods

A total of 57,053 adults (aged 50–64 years) enrolled in the Danish Diet, Cancer, and Health cohort (1993–1997) were followed in the National Patients Registry for admissions for asthma (DJ45–46) and COPD (DJ40–44) and vital status. Asthma–COPD overlap was defined as at least one hospital admission for asthma and one for COPD (different time points), and incident asthma–COPD overlap as at least one of the diagnoses occurring after enrollment into the Diet, Cancer, and Health cohort.

Results

A total of 1,845 (3.2%) and 4,037 (7.1%) participants had admissions for asthma and COPD, respectively, with 662 (1.2%) participants with asthma–COPD overlap. Incidence rate of asthma–COPD overlap per 1,000 person-years was higher in women (0.73) than in men (0.54) (P<0.02). Mortality rate was higher in asthma–COPD overlap (25.9 per 1,000 person-years) compared with COPD (23.1, P<0.05) and asthma (7.9, P<0.001) alone. Compared to COPD alone, mortality was higher in women with asthma–COPD overlap (19.6 and 25.5, respectively; P<0.01), and the excess mortality rate for asthma–COPD overlap patients was most prominent for younger age groups (12.9 compared to 7.2 and 4.6 for COPD and asthma alone, respectively; P<0.01).

Conclusion

This large population-based study revealed a higher incidence of severe asthma–COPD overlap in women compared to men, and furthermore that all-cause mortality is higher in women and younger subjects with asthma–COPD overlap compared with those with asthma or COPD alone.

Asthma-chronic obstructive pulmonary disease overlap syndrome - Literature review and contributions towards a Portuguese consensus

INTRODUCTION

Phenotypic overlap between the two main chronic airway pulmonary diseases, asthma and chronic obstructive pulmonary disease (COPD), has been the subject of debate for decades, and recently the nomenclature of asthma-COPD overlap syndrome (ACOS) was adopted for this condition. The definition of this entity in the literature is, however, very heterogeneous, it is therefore important to define how it applies to Portugal.

METHODS

A literature review of ACOS was made in a first phase resulting in the drawing up of a document that was later submitted for discussion among a panel of chronic lung diseases experts, resulting in reflexions about diagnosis, treatment and clinical guidance for ACOS patients.

RESULTS

There was a consensus among the experts that the diagnosis of ACOS should be considered in the concomitant presence of: clinical manifestations characteristic of both asthma and COPD, persistent airway obstruction (post-bronchodilator FEV₁/FVC<0.7), positive response to bronchodilator test (increase in FEV₁ of ≥200mL and ≥12% from baseline) and current or past history of smoking or biomass exposure. In reaching diagnosis, the presence of peripheral eosinophilia (>300eosinophils/μL or >5% of leukocytes) and previous history of atopy should also be considered. The recommended first line pharmacological treatment in these patients is the ICS/LABA association; if symptomatic control is not achieved or in case of clinical severity, triple therapy with ICS/LABA/LAMA may be used. An effective control of the exposure to risk factors, vaccination, respiratory rehabilitation and treatment of comorbidities is also important.

CONCLUSIONS

The creation of initial guidelines on ACOS, which can be applied in the Portuguese context, has an important role in the generation of a broad nationwide consensus. This will give, in the near future, a far better clinical, functional and epidemiological characterization of ACOS patients, with the ultimate goal of achieving better therapeutic guidance.

Airflow obstruction: is it asthma or is it COPD?

Despite the availability of guideline recommendations, diagnostic confusion between COPD and asthma appears common, and often it is very difficult to decide whether the obstruction is caused by asthma or COPD in a patient with airway obstruction. However, there are well-defined features that help in differentiating asthma from COPD in the presence of fixed airflow obstruction. Nonetheless, the presentations of asthma and COPD can converge and mimic each other, making it difficult to give these patients a diagnosis of either condition. The association of asthma and COPD in the same patient has been designated mixed asthma–COPD phenotype or overlap syndrome. However, since the absence of a clear definition and the inclusion of patients with different characteristics under this umbrella term, it may not facilitate treatment decisions, especially in the absence of clinical trials addressing this heterogeneous population. We are realizing that neither asthma nor COPD are single diseases, but rather syndromes consisting of several endotypes and phenotypes, consequently comprising a spectrum of diseases that must be recognized and adequately treated with targeted therapy. Therefore, we must treat patients by personalizing therapy on the basis of those treatable traits present in each subject.