Diagnosis Of asthma-COPD Overlap Syndrome Research Articles

Overlapping of Asthma and Chronic Obstructive Pulmonary Disease: A Literature Review

: Asthma and chronic obstructive pulmonary disease (COPD) are the most common chronic respiratory diseases with significant morbidity in the world. Although these diseases have different characteristics, some patients share symptoms and clinical findings of both diseases, so-called asthma-COPD overlap syndrome (ACOS). Although there is no gold standard for the diagnosis of ACOS, it is usually defined as an increased variability of airflow in the respiratory tract. Patients with ACOS are identified with distinct phenotypes such as the increased reversibility of airflow obstruction, eosinophilic bronchial and systemic inflammation, and the increased reaction to inhaled corticosteroids compared to COPD patients. The evidence indicates that ACOS patients are likely to have more dyspnea and cough, more serious symptoms, more hospital admissions, and higher mortality rate. Despite these complex conditions, ACOS patients have been eliminated from clinical trials of asthma and COPD and there is little evidence about their clinical decisions. The current study was conducted to review the epidemiology, clinical symptoms, diagnosis, and treatment of ACOS as the first stage of correct diagnosis and appropriate management of this syndrome in databases such as PubMed, Elsevier, Google Scholar, SID, Magiran, Google search engine, and so on.

Is ACOS an independent nosology? Clinical signs and diagnosis of ACOS

The aim of this study was to analyze inflammation features and possible causes of asthma-COPD overlap syndrome (ACOS). Methods. Clinical examination was performed for all patients included in the study. Blood levels of alpha-1-antitripsin (AAT), immunoglobulin (Ig) G and E antibodies against four bacterial antigens (Streptococcus pneumoniae, Haemophilus influenzae, Neisseria perflava, and Staphylococcus aureus), and lung function were measured in all the patients. Results. The study involved 175 patients including 78 patients with bronchial asthma, 39 patients with ACOS, 38 patients with COPD, and 20 healthy individuals. AAT blood level was reversely related to lung function and to increased IgG-antibody levels against bacterial antigens. Conclusion. Due to this fact, the authors suppose that the ACOS should be considered as an independent nosology distinct from asthma and COPD, and related to microbial inflammation and AAT level.

Osteoporosis in Patients with Asthma-Chronic Obstructive Pulmonary Disease Overlap Syndrome.

BackgroundOsteoporosis is a common disease that occurs comorbidly in patients with chronic inflammatory airway diseases, including asthma, chronic obstructive pulmonary disease (COPD), and asthma-COPD overlap syndrome (ACOS). However, the prevalence of osteoporosis in patients with ACOS has not widely been evaluated. Therefore, we investigated the prevalence of osteoporosis and its relationship with the clinical parameters of patients with asthma, COPD, and ACOS.MethodsThis was a retrospective, cross-sectional study. Bone mineral density (BMD), lung function tests, and disease status evaluations were conducted.ResultsA total of 321 patients were enrolled: 138 with asthma, 46 with ACOS, and 137 with COPD. One hundred and ninety-three patients (60.1%) were diagnosed with osteoporosis (53.6% of asthma, 65.2% of ACOS, and 65.0% of COPD). Patients with ACOS showed a significantly lower BMD and T-score than did those with asthma. In addition to age, sex, and body mass index (BMI), which were previously reported to be associated with BMD, BMD also had a negative correlation with the diagnosis of ACOS, as compared to a diagnosis of asthma, after adjusting for age, sex, BMI, smoking, and inhaled corticosteroid use (p=0.001). Among those patients with COPD and ACOS, BMD was negatively associated with the COPD Assessment Test (CAT) after adjustment (p<0.001). Inhaled corticosteroid was not associated with the prevalence of osteoporosis and BMD.ConclusionPatients with ACOS, particularly aged and lean women, should be more carefully monitored for osteoporosis as compared to patients with asthma.

Consenso sobre el solapamiento de asma y EPOC (ACO) entre la Guía española de la EPOC (GesEPOC) y la Guía Española para el Manejo del Asma (GEMA)

Following a proposal by the Spanish Society of Pulmonology and Thoracic Surgery (SEPAR), sponsor of the Spanish COPD Guidelines (GesEPOC) and the Spanish Guidelines on the Management of Asthma (GEMA), authors of both papers have unified the criteria for the diagnosis of asthma-COPD overlap syndrome (ACOS).This consensus defines ACOS as the presence in a given patient of three elements: significant smoking exposure, chronic airflow limitation and asthma. Diagnosis is confirmed when a patient (35years of age or older), smoker or ex-smoker of more than 10 pack-years, presents airflow limitation (post-bronchodilator FEV1/FVC<0.7) that persists after treatment with bronchodilators and inhaled corticosteroids (even after systemic corticosteroids in selected cases), and an objective current diagnosis of asthma (according to GEMA criteria). In cases in which the diagnosis of asthma cannot be demonstrated, marked positive results on a bronchodilator test (FEV1≥15% and ≥400mL) or elevated blood eosinophil count (≥300eosinophils/μL) will also be diagnostic of ACOS.The opinion of another 33 experts who had not participated in the consensus was sought using a modified Delphi survey. Up to 80% of respondents gave a very positive opinion of the consensus, and declared that it was better than other previous proposals. The GesEPOC-GEMA consensus on ACOS provides a unique perspective of the diagnostic problem, using a simple proposal and a pragmatic diagnostic algorithm that can be applied at any healthcare level.

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

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

A Belgian survey on the diagnosis of asthma-COPD overlap syndrome.

IntroductionPatients with chronic airway disease may present features of both asthma and COPD, commonly referred to as asthma–COPD overlap syndrome (ACOS). Recommendations on their diagnosis are diffuse and inconsistent. This survey aimed to identify consensus on criteria for diagnosing ACOS.MethodsA Belgian expert panel developed a survey on ACOS diagnosis, which was completed by 87 pulmonologists. Answers chosen by ≥70% of survey respondents were considered as useful criteria for ACOS diagnosis. The two most frequently selected answers were considered as major criteria, others as minor criteria. The expert panel proposed a minimal requirement of two major criteria and one minor criterion for ACOS diagnosis. Respondents were also asked which criteria are important for considering inhaled corticosteroids prescription in a COPD patient.ResultsTo diagnose ACOS in COPD patients, major criteria were “high degree of variability in airway obstruction over time (change in forced expiratory volume in 1 second ≥400 mL)” and “high degree of response to bronchodilators (>200 mL and ≥12% predicted above baseline)”. Minor criteria were “personal/family history of atopy and/or IgE sensitivity to ≥1 airborne allergen”, “elevated blood/sputum eosinophil levels and/or increased fractional exhaled nitric oxide”, “diagnosis of asthma <40 years of age”; “symptom variability”, and “age (in favor of asthma)”. To diagnose ACOS in asthma patients, major criteria were “persistence of airflow obstruction over time (forced expiratory volume in 1 second/forced vital capacity ratio <0.7)” and “exposure to noxious particles/gases, with ≥10 pack-years for (ex-)smokers”; minor criteria were “lack of response on acute bronchodilator test”; “reduced diffusion capacity”; “limited variability in airway obstruction”; “age >40 years”; “emphysema on chest computed tomography scan”.ConclusionSpecific criteria were identified that may guide physicians to a more uniform diagnostic approach for ACOS in COPD or asthma patients. These criteria are largely similar to those used to prescribe inhaled corticosteroids in COPD.

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

IntroductionPhenotypic 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. MethodsA 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. ResultsThere 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. ConclusionsThe 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.

Computer quantification of "angle of collapse" on maximum expiratory flow volume curve for diagnosing asthma-COPD overlap syndrome.

BackgroundIn a previous study, we demonstrated that asthma patients with signs of emphysema on quantitative computed tomography (CT) fulfill the diagnosis of asthma-COPD overlap syndrome (ACOS). However, quantitative CT measurements of emphysema are not routinely available for patients with chronic airway disease, which limits their application. Spirometry was a widely used examination tool in clinical settings and shows emphysema as a sharp angle in the maximum expiratory flow volume (MEFV) curve, called the “angle of collapse (AC)”. The aim of this study was to investigate the value of the AC in the diagnosis of emphysema and ACOS.MethodsThis study included 716 participants: 151 asthma patients, 173 COPD patients, and 392 normal control subjects. All the participants underwent pulmonary function tests. COPD and asthma patients also underwent quantitative CT measurements of emphysema. The AC was measured using computer models based on Matlab software. The value of the AC in the diagnosis of emphysema and ACOS was evaluated using receiver-operating characteristic (ROC) curve analysis.ResultsThe AC of COPD patients was significantly lower than that of asthma patients and control subjects. The AC was significantly negatively correlated with emphysema index (EI; r=−0.666, P<0.001), and patients with high EI had a lower AC than those with low EI. The ROC curve analysis showed that the AC had higher diagnostic efficiency for high EI (area under the curve =0.876) than did other spirometry parameters. In asthma patients, using the AC ≤137° as a surrogate criterion for the diagnosis of ACOS, the sensitivity and specificity were 62.5% and 89.1%, respectively.ConclusionThe AC on the MEFV curve quantified by computer models correlates with the extent of emphysema. The AC may become a surrogate marker for the diagnosis of emphysema and help to diagnose ACOS.

Inflammatory biomarkers in asthma-COPD overlap syndrome.

BackgroundThe clinical phenotypes and underlying mechanisms of asthma-COPD overlap syndrome (ACOS) remain elusive. This study aimed to investigate a comparison of COPD patients with and without ACOS, focusing on inflammatory biomarkers, in an outpatient COPD cohort.MethodsWe conducted a cross-sectional study analyzing prospectively collected data from the Ishinomaki COPD Network registry. All participants were diagnosed with COPD, confirmed by using spirometry, and were aged 40–90 years and former smokers. Patients with features of asthma including both variable respiratory symptoms and variable expiratory airflow limitation were identified and defined as having ACOS. Then, the inflammatory biomarkers such as fractional exhaled nitric oxide level, blood eosinophil count and percentage, total immunoglobulin E (IgE) level, and presence of antigen-specific IgE were evaluated.ResultsA total of 257 patients with COPD were identified, including 37 (14.4%) with ACOS. Patients with ACOS tended to be younger, have a shorter smoking history, and use more respiratory medications, especially inhaled corticosteroids and theophylline. Mean fractional exhaled nitric oxide level was significantly higher in those with ACOS than in those without ACOS (38.5 parts per billion [ppb] vs 20.3 ppb, P<0.001). Blood eosinophil count and percentage were significantly increased in those with ACOS (295/mm3 vs 212/mm3, P=0.032; 4.7% vs 3.2%, P=0.003, respectively). Total IgE level was also significantly higher, and presence of antigen-specific IgE was observed more frequently in patients with ACOS. Receiver operating characteristic curve analysis indicated that the sensitivity and specificity of these biomarkers were relatively low, but combinations of these biomarkers showed high specificity for ACOS diagnosis.ConclusionThese results provide evidence that these inflammatory biomarkers can be used to support the diagnosis of ACOS.

Diagnostic performance of the measurement of nitric oxide in exhaled air in the diagnosis of COPD phenotypes

IntroductionCOPD is a highly heterogeneous disease that has a serious impact on affected populations. Patients share some of the features of bronchial asthma, often summarized under the term ACOS (asthma-COPD overlap syndrome). The objective of this study is to evaluate the utility of the measurement of nitric oxide in exhaled air (FENO50) in the diagnosis of COPD phenotypes. Material and methodsThe study comprised cross-sectional observation of patients receiving assistance during a respiratory outpatient visit. Patient data was collected on lung function, FENO, questionnaires scoring CAT®(COPD Assessment Test), and COPD clinical phenotype. Results192 patients were studied: 103 with COPD; 16 healthy non-smokers; 30 healthy smokers; and 43 asthmatics. COPD patients were grouped by phenotype: 34 non exacerbators (33.0%); 22 ACOS (21.3%); 13 frequent exacerbators with emphysema (12.6%); and 34 frequent exacerbators with chronic bronchitis (33.0%). ACOS patients showed significantly higher FENO50 values compared to the others after adjustments for confounding factors. FENO50 demonstrated greater diagnostic accuracy than the bronchodilator test (BT) in the diagnosis of ACOS and COPD phenotypes (AUC 0.79 vs 0.74), with an optimal cut-off value of 19 ppb (sensitivity 0.68, specificity 0.75). ConclusionsPatients with COPD have different levels of FENO50 depending on the COPD phenotype. FENO50 measurement provides better diagnostic accuracy than BT, with an optimal cut-off value of 19 ppb.

How can Patients With Asthma-COPD Overlap Syndrome in Clinical Practice be Identified?

In a recent consensus meeting of 26 Spanish specialists, 85% of the participants were in agreement about the existence of a mixed COPD-asthma phenotype, known as asthma-COPD overlap syndrome (ACOS). However, there was less agreement on the characteristics that defined this phenotype and how it can be identified in routine clinical practice.1 The need for an agreement on the significance of ACOS led to the first consensus meeting aimed at defining ACOS as a COPD phenotype. This was necessary in view of the emerging body of evidence on COPD patients with asthmatic characteristics who respond better to treatment with inhaled corticosteroids (ICS). In this meeting, major and minor criteria for the diagnosis of ACOS were defined2; however, subsequent studies have shown that these criteria were excessively restrictive, and that they applied to only a small proportion of patients who may have ACOS.3 Compared to the excessively restrictive criteria of the Spanish consensus, the recent criteria from the Global Initiative for Asthma (GINA) and the Global Initiative for Obstructive Lung Disease (GOLD) appear imprecise and ambiguous. These organizations provide a list of characteristics associated with asthma and another list of characteristics associated with COPD. Doctors are expected to tick the characteristics which apply to the patient, and if the number of ticks in each list is similar, the patient probably has ACOS.4 There is no indication of how many ticks are required, and all ticks have the same weight, even though not all characteristics have the same value when identifying asthma or COPD. Returning to the opinion of the Spanish experts, we find that the most relevant ACOS diagnostic criteria were: prior diagnosis of asthma in a COPD patient (according to 88% of experts); significant tobacco consumption (73%); and post-bronchodilator FEV1/FVC < 0.7 (69%).1

The asthma-COPD overlap syndrome: a new entity?

Asthma and COPD are the most frequent chronic respiratory diseases. Although they have different characteristics, some individuals share features of both diseases, which has been called the asthma-COPD overlap syndrome (ACOS). Although there is not a universally accepted definition for ACOS, it was initially defined as symptoms of increased variability of airflow in association with an incompletely reversible airflow obstruction. The most recent COPD guidelines include this phenotype and its diagnostic features. Patients with ACOS are usually characterized by increased reversibility of airflow obstruction, eosinophilic bronchial and systemic inflammation, and increased response to inhaled corticosteroids, compared with COPD patients. The relevance of the ACOS is the need to identify patients with COPD who may have underlying eosinophilic inflammation that responds better to inhaled corticosteroids. Until new diagnostic tools are developed, a previous diagnosis of asthma in a patient with COPD can be a reliable criterion to suspect ACOS in a patient with COPD but a comprehensive approach may be required in most cases for a definitive diagnosis of ACOS.

036. Asthma and chronic obstructive pulmonary disease (COPD): the importance of their coexistence

Asthma is a heterogenous illness, characterized by airway inflammation and expressing mainly with wheezing, dyspnea, chest tightness and cough. These symptoms vary, regarding intensity and time. Chronic Obstructive Pulmonary Disease (COPD) is a preventable and treatable disease, where you can notice persistent airflow obstruction, usually progressive. Enhanced chronic inflammatory response in noxious particles or gases is associated with COPD. There is a strong relation of asthma with allergies and atopy, displayed mainly in childhood, while COPD is related with smoking and concerns people over 40 years old, having worse prognosis compared to asthma. Multiple recent reviews of literature try to define the asthma-COPD coexistence, using mainly the word overlap. American Thoracic Society-ATS guidelines of 1995 already, define asthma, chronic bronchitis, emphysema, COPD, airway obstruction, recognizing 11 different syndromes, with overlap in six of them. There are three common clinical characteristics in airway diseases: airway inflammation, airway obstruction and bronchial hyper responsiveness. The inflammation in asthma is mostly eosinophilic, driven by CD4 cells, in contrast with COPD where inflammation is neutrophilic, driven by CD8 cells. Eosinophilic inflammation is adequately controlled with steroids, while smoking promotes neutrophilic inflammation which is corticosteroids resistant. Remodeling, especially of distal, small airways happening in long standing asthma, as well as in COPD, is responsible for pulmonary function decline (airway obstruction). It is impressive the fact that up to 16% of asthmatics develop insufficient airway reversibility, after a period of 21-33 years. Bronchial hyper responsiveness is present in almost all asthmatics and in up to 2/3 of COPD patients. A cohort study proved that 17% of general population had positive challenge test in metacholine, while 50% of them were asymptomatic. Why overlap happens? “Dutch hypothesis” supports the theory that asthma and bronchial hyper responsiveness evolve in COPD later, and that asthma, COPD, chronic bronchitis and emphysema constitute different expressions of a single disease that are affected of host and environmental factors. In the biomarkers field, recent clinical trials have shown that increased levels of sputum NGAL (Neutrophil Gelatinase-Associated Lipocalin), puts the diagnosis of asthma-COPD overlap syndrome, and that overlap patients have elevated values of IL-6. Summarizing, given the fact that overlap patients are presenting more frequent exacerbations, have poorer quality of life, a more rapid decline in lung function, and higher hospital impact and mortality, in comparison to asthmatics or COPD patients, it is crucial to study further the pathogenesis of overlap syndrome, in order to understand and even to modificate the progressive functionality decline that leads to COPD.