The clinical and genetic features of COPD-asthma overlap syndrome

Understanding asthma-chronic obstructive pulmonary disease overlap syndrome

Asthma-chronic obstructive pulmonary disease overlap syndrome (ACOS) is a loosely-defined clinical entity referring to patients who exhibit characteristics of both asthma and chronic obstructive pulmonary disease (COPD). Clinical definitions and classifications for ACOS vary widely, which impacts our understanding of prevalence, diagnosis and treatment of the condition. This literature review was therefore conducted to characterize the prevalence of ACOS and the effect of different disease definitions on these estimates, as this has not previously been explored. From an analysis of English language literature published from 2000 to 2014, the estimated prevalence of ACOS ranges from 12.1% to 55.2% among patients with COPD and 13.3%-61.0% among patients with asthma alone. This variability is linked to differences in COPD and asthma diagnostic criteria, disease ascertainment methods (spirometry-based versus clinical or symptom-based diagnoses and claims data), and population characteristics including age, gender and smoking. Understanding the reasons for differences in prevalence estimates of ACOS across the literature may help guide decision making on the most appropriate criteria for defining ACOS and aid investigators in designing future ACOS clinical studies aimed at effective treatment.

A diagnostic approach and natural course of a patient with asthma-COPD overlap syndrome

The diagnostic criteria of asthma-chronic obstructive pulmonary disease (COPD) overlap syndrome (ACOS) advocated by the Global Initiative for Asthma (GINA)/Global Initiative for Chronic Obstructive Lung Disease (GOLD) are somewhat complicated, and limited data are available regarding how ACOS patients respond to current medications. We present a case of a 64-year-old man with ACOS. With features favoring asthma including childhood asthma history with intermittent episodes of dyspnea at night, elevated blood eosinophil count and total IgE, increased forced expiratory volume in 1 s (FEV 1) after bronchodilator (>200 mL and >12% from baseline), and positive skin prick tests, he also had features favoring COPD such as heavy smoker, persistent exertional dyspnea, and airflow limitation after inhaled therapy. Over 5-year follow up, our patient experienced a single episode of moderate exacerbation. However, post-bronchodilator FEV 1 decreased by 240 mL for 4 years (-60 mL/year) after 1.5 years of treatment, indicating rapid lung function decline. Longitudinal studies are necessary to assess optimal interventions and natural course of ACOS.

Asthma-COPD overlap syndrome (ACOS): A diagnostic challenge

Asthma-chronic obstructive pulmonary disease (COPD) overlap syndrome (ACOS) is characterized by persistent airflow limitation with several features usually associated with asthma and several features usually associated with COPD. ACOS may be a special phenotype of a spectrum of chronic obstructive airway diseases, in which asthma and COPD are at the two opposite ends. The prevalence of ACOS varies considerably due to differing criteria being applied for diagnosis. Patients with ACOS utilize a large proportion of medical resources. They are associated with more frequent adverse outcomes than those with asthma or COPD alone. ACOS is currently a diagnostic challenge for physicians because there are no specific biomarkers to differentiate ACOS from asthma or COPD. The approach to diagnosing ACOS depends on the population from which the patient originated. The management of ACOS should be individualized to ensure the most effective treatment with minimal side effects. In this paper, we review the diagnostic criteria of ACOS used in previous studies, propose practical approaches to diagnosing and managing ACOS and raise some research questions related to ACOS.

Childhood pneumonia increases risk for chronic obstructive pulmonary disease: the COPDGene study

Background

Development of adult respiratory disease is influenced by events in childhood. The impact of childhood pneumonia on chronic obstructive pulmonary disease (COPD) is not well defined. We hypothesize that childhood pneumonia is a risk factor for reduced lung function and COPD in adult smokers.

Methods

COPD cases and control smokers between 45–80 years old from the United States COPDGene Study were included. Childhood pneumonia was defined by self-report of pneumonia at <16 years. Subjects with lung disease other than COPD or asthma were excluded. Smokers with and without childhood pneumonia were compared on measures of respiratory disease, lung function, and quantitative analysis of chest CT scans.

Results

Of 10,192 adult smokers, 854 (8.4 %) reported pneumonia in childhood. Childhood pneumonia was associated with COPD (OR 1.40; 95 % CI 1.17-1.66), chronic bronchitis, increased COPD exacerbations, and lower lung function: post-bronchodilator FEV₁ (69.1 vs. 77.1 % predicted), FVC (82.7 vs. 87.4 % predicted), FEV₁/FVC ratio (0.63 vs. 0.67; p < 0.001 for all comparisons). Childhood pneumonia was associated with increased airway wall thickness on CT, without significant difference in emphysema. Having both pneumonia and asthma in childhood further increased the risk of developing COPD (OR 1.85; 95 % CI 1.10-3.18).

Conclusions

Children with pneumonia are at increased risk for future smoking-related lung disease including COPD and decreased lung function. This association is supported by airway changes on chest CT scans. Childhood pneumonia may be an important factor in the early origins of COPD, and the combination of pneumonia and asthma in childhood may pose the greatest risk.

Clinical trials registration

ClinicalTrials.gov, NCT00608764 (Active since January 28, 2008).

Electronic supplementary material

The online version of this article (doi:10.1186/s12931-015-0273-8) contains supplementary material, which is available to authorized users.

COPD and its comorbidities: Impact, measurement and mechanisms

Chronic obstructive pulmonary disease (COPD) frequently coexists with other conditions often known as comorbidities. The prevalence of most of the common comorbid conditions that accompany COPD has been widely reported. It is also recognized that comorbidities have significant health and economic consequences. Nevertheless, there is scant research examining how comorbidities should be assessed and managed in the context of COPD. Also, the underlying mechanisms linking COPD with its comorbidities are still not fully understood. Owing to these knowledge gaps, current disease-specific approaches provide clinicians with little guidance in terms of managing comorbid conditions in the clinical care of multi-diseased COPD patients. This review discusses the concepts of comorbidity and multi-morbidity in COPD in relation to the overall clinical outcome of COPD management. It also summarizes some of the currently available clinical scores used to measure comorbid conditions and their prognostic abilities. Furthermore, recent developments in the proposed mechanisms linking COPD with its comorbidities are discussed.

Application of nitric oxide measurements in clinical conditions beyond asthma

Fractional exhaled nitric oxide (FeNO) is a convenient, non-invasive method for the assessment of active, mainly Th2-driven, airway inflammation, which is sensitive to treatment with standard anti-inflammatory therapy. Consequently, FeNO serves as a valued tool to aid diagnosis and monitoring in several asthma phenotypes. More recently, FeNO has been evaluated in several other respiratory, infectious, and/or immunological conditions. In this short review, we provide an overview of several clinical studies and discuss the status of potential applications of NO measurements in clinical conditions beyond asthma.

The asthma-COPD overlap syndrome: towards a revised taxonomy of chronic airways diseases?

Most research of treatments for airways diseases has been restricted to patients who meet standard definitions of either chronic obstructive pulmonary disease (COPD) or asthma, yet to distinguish COPD from asthma in adult patients who have clinical features of both can be challenging. Treatment guidelines provide scant advice on how such patients should be managed. With increasing recognition that asthma and COPD are heterogeneous diseases, attention has been directed to the needs of a group of patients with what is now termed asthma-COPD overlap syndrome (ACOS), particularly in view of the high morbidity in this population. This Review considers the epidemiology, mechanisms of disease, current attempts to define and diagnose ACOS, existing and potential treatment options, and new approaches to the phenotyping and taxonomy of airway diseases.

Clinical characteristics of the asthma-COPD overlap syndrome--a systematic review

Background and objective

In recent years, the so-called asthma–chronic obstructive pulmonary disease (COPD) overlap syndrome (ACOS) has received much attention, not least because elderly individuals may present characteristics suggesting a diagnosis of both asthma and COPD. At present, ACOS is described clinically as persistent airflow limitation combined with features of both asthma and COPD. The aim of this paper is, therefore, to review the currently available literature focusing on symptoms and clinical characteristics of patients regarded as having ACOS.

Methods

Based on the preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines, a systematic literature review was performed.

Results

A total of 11 studies met the inclusion criteria for the present review. All studies dealing with dyspnea (self-reported or assessed by the Medical Research Council dyspnea scale) reported more dyspnea among patients classified as having ACOS compared to the COPD and asthma groups. In line with this, ACOS patients have more concomitant wheezing and seem to have more cough and sputum production. Compared to COPD-only patients, the ACOS patients were found to have lower FEV₁% predicted and FEV₁/FVC ratio in spite of lower mean life-time tobacco exposure. Furthermore, studies have revealed that ACOS patients seem to have not only more frequent but also more severe exacerbations. Comorbidity, not least diabetes, has also been reported in a few studies, with a higher prevalence among ACOS patients. However, it should be acknowledged that only a limited number of studies have addressed the various comorbidities in patients with ACOS.

Conclusion

The available studies indicate that ACOS patients may have more symptoms and a higher exacerbation rate than patients with asthma and COPD only, and by that, probably a higher overall respiratory-related morbidity. Similar to patients with COPD, ACOS patients seem to have a high occurrence of comorbidity, including diabetes. Further research into the ACOS, not least from well-defined prospective studies, is clearly needed.

The asthma-chronic obstructive pulmonary disease overlap syndrome (ACOS): opportunities and challenges

PURPOSE OF REVIEW

Some individuals share characteristics of asthma and chronic obstructive pulmonary disease (COPD). The asthma-COPD overlap syndrome (ACOS) has been defined as symptoms of increased variability of airflow in association with an incompletely reversible airflow obstruction. In this review, we present the latest findings in the diagnosis, characterization and management of ACOS.

RECENT FINDINGS

Around 15-20% of COPD patients may have an ACOS. Patients with ACOS are characterized by increased reversibility of airflow obstruction, eosinophilic bronchial and systemic inflammation, and increased response to inhaled corticosteroids, compared with the remaining patients with COPD. Patients with ACOS have more frequent exacerbations, more wheezing and dyspnoea, but similar cough and sputum production compared with COPD.

SUMMARY

The relevance of the ACOS is to identify patients with COPD who may have underlying eosinophilic inflammation that responds to inhaled corticosteroids. So far, the previous diagnosis of asthma in a patient with COPD is the more reliable criterion for ACOS. Ongoing studies will clarify if concentrations of blood eosinophils may be useful to identify this subgroup of patients with COPD. If this is the case, the interest of ACOS may shift to that of eosinophilic COPD, which is easier to diagnose and has clear therapeutic implications.

The Impact of Coexisting Asthma, Chronic Obstructive Pulmonary Disease and Tuberculosis on Survival in Patients with Lung Squamous Cell Carcinoma

BACKGROUND

Pulmonary diseases [asthma, chronic obstructive pulmonary disease (COPD), and tuberculosis (TB)] are associated with lung cancer mortality. However, the relationship between coexisting pulmonary diseases and survival in patients with lung squamous cell carcinoma (SqCC) has not been well defined.

METHODS

Patients newly diagnosed with SqCC between 2003 and 2008 were identified by linking the National Health Insurance Research Database and Taiwan Cancer Registry Database. Cases with SqCC were followed up until death, loss to follow-up, or study end in 2010. Information on health status, date of death and the main causes of death was ascertained from the National Death Registry Database. Cox proportional hazard regression was used to calculate the hazard ratio (HR) of coexisting asthma, COPD and/or TB.

RESULTS

During the study period, a total of 5406 cases with SqCC were enrolled. For all cause-mortality, HRs were 1.08 [95% confidence interval (CI), 0.99-1.18], 1.04 (95% CI, 0.97-1.12), and 1.14 (95% CI, 1.00-1.31) for individuals with asthma, COPD, and TB, respectively. Specifically, among men with coexisting pulmonary diseases, the HRs were 1.56 (95% CI, 1.23-1.97) and 1.11 (95% CI, 1.00-1.24) for individuals with asthma+COPD+TB and asthma+COPD, respectively. Among male patients with stage III SqCC, HRs were 3.41 (95%CI, 1.27-9.17) and 1.65 (95%CI, 1.10-2.47) for individuals with asthma+TB and asthma+COPD+TB, respectively. Among male patients with stage IV SqCC, HRs were 1.40 (95%CI, 1.00-1.97) and 1.25 (95%CI, 1.03-1.52) for individuals with asthma+ COPD+TB and asthma. Among female patients with stage I and II, HR was 0.19 (95%CI, 005-0.77) for individuals with asthma.

CONCLUSIONS

Coexisting pulmonary diseases increased the risk of mortality from SqCC in male patients. For female patients with early stage SqCC, pre-existing asthma decreased mortality. These patients deserve greater attention while undergoing cancer treatment.

The asthma COPD overlap syndrome (ACOS)

Asthma and chronic obstructive pulmonary disease (COPD) have traditionally been viewed as distinct clinical entities. Recently, however, much attention has been focused on patients with overlapping features of both asthma and COPD: those with asthma COPD overlap syndrome (ACOS). Although no universal definition criteria exist, recent publications attempted to define patients with ACOS based on differences in clinical features, radiographic findings, and diagnostic tests. Patients with ACOS make up a large percentage of those with obstructive lung disease and have a higher overall health-care burden. Identifying patients with ACOS has significant therapeutic implications particularly with the need for early use of inhaled corticosteroids and the avoidance of use of long-acting bronchodilators alone in such patients. However, unlike asthma and COPD, no evidence-based guidelines for the management of ACOS currently exist. Future research is needed to improve our understanding of ACOS and to achieve the best management strategies.

Comparison of in-hospital mortality in patients with COPD, asthma and asthma-COPD overlap exacerbations

BACKGROUND AND OBJECTIVE

Obstructive airway diseases, such as asthma and chronic obstructive pulmonary disease (COPD), have airflow limitation associated with chronic inflammation. Using a national inpatient database in Japan, we aimed to evaluate factors affecting in-hospital mortality in patients with asthma, COPD or asthma-COPD overlap (ACO).

METHODS

We retrospectively collected data for inpatients (age >40 years) with exacerbation of COPD and/or asthma in 1073 hospitals across Japan between July 2010 and May 2013. We performed multivariable logistic regression analysis to examine the association of various factors with all-cause in-hospital mortality, including diagnosis of ACO, asthma alone and COPD alone.

RESULTS

Of 30 405 eligible patients, in-hospital mortality in patients with ACO, asthma alone and COPD alone was 2.3%, 1.2% and 9.7%, respectively. COPD patients had a significantly higher mortality than ACO patients (odds ratio 1.96; 95% confidence interval: 1.38-2.79); patients with asthma alone showed lower mortality (0.70; 0.50-0.97). Higher mortality was also significantly associated with older age, male gender, lower body mass index, more severe dyspnoea, lower level of consciousness, worse activities of daily life and higher daily dose of corticosteroids.

CONCLUSION

Asthma alone was associated with lower mortality, but COPD alone was associated with higher mortality than ACO.

Asthma-COPD overlap 2015: now we are six

BACKGROUND

The overlap between asthma and COPD is increasingly recognised. This review examines the new insights, treatment and remaining knowledge gaps for asthma-COPD overlap.

METHOD

A systematic literature review of cluster analyses of asthma and COPD was performed. Articles from 2009 to the present dealing with prevalence, morbidity and treatment of asthma-COPD overlap were identified and reviewed.

RESULTS

Asthma-COPD overlap was consistently recognised in studies using a variety of different study designs and sampling. The prevalence was approximately 20% in patients with obstructive airways diseases. Asthma-COPD overlap was associated with increased morbidity and possibly an increased mortality and comorbidity. There was evidence of a heterogeneous pattern of airway inflammation that included eosinophilic (in adult asthma), neutrophilic or mixed patterns (in severe asthma and COPD). Systemic inflammation was present in asthma-COPD overlap and resembled that of COPD. Within asthma-COPD overlap, there is evidence of different subgroups, and recognition using bronchodilator responsiveness has not been successful. Guidelines generally recommend a serial approach to assessment, with treatment recommendations dominated by an asthma paradigm. Research is needed into key clinical features that impact outcome, mechanisms and treatment approaches in asthma-COPD overlap. Identifying and treating disease components by multidimensional assessment shows promise.

CONCLUSIONS

Asthma-COPD overlap has drawn attention to the significant heterogeneity that exists within obstructive airway diseases. It should be replaced by novel approaches that identify and manage the components of this heterogeneity, such as multidimensional assessment and treatment. Future research is needed to test these novel and personalised approaches.

Comorbidity in chronic obstructive pulmonary disease

Patients with chronic obstructive pulmonary diseases (COPD) often experience comorbid conditions. The most common comorbidities that have been associated with COPD include cardiovascular diseases, lung cancer, metabolic disorder, osteoporosis, anxiety and depression, skeletal muscle dysfunction, cachexia, gastrointestinal diseases, and other respiratory conditions. Not only are comorbidities common but they also considerably influence disease prognosis and patients׳ health status, and are associated with poor clinical outcomes. However, perusal of literature indicates that little has been done so far to effectively assess, manage, and treat comorbidities in patients with COPD. The aim of this review is to comprehensively narrate the comorbid conditions that often coexist with COPD, along with their reported prevalence and their significant impacts in the disease management of COPD. A perspective on integrated disease management approaches for COPD is also discussed.

Role of p53 in lung tissue remodeling

The tumor suppressor gene p53 regulates a wide range of cellular processes including cell cycle progression, proliferation, apoptosis and tissue development and remodeling. Lung cell apoptosis and tissue remodeling have critical roles in many lung diseases. Abnormal proliferation or resistance to apoptosis of lung cells will lead to structural changes of many lung tissues, including the pulmonary vascular wall, small airways and lung parenchyma. Among the many lung diseases caused by vascular cell apoptosis and tissue remodeling are chronic obstructive pulmonary disease, bronchial asthma and pulmonary arterial hypertension. Recent advances in biology and medicine have provided new insights and have resulted in new therapeutic strategies for tissue remodeling in human and animal models. This review is focused on lung disease susceptibility associated with the p53 pathway and describes molecular mechanisms upstream and downstream of p53 in lung tissue remodeling. Improved understanding of structural changes associated with pulmonary vascular remodeling and lung cell apoptosis induced by the p53 pathway may new provide therapeutic targets.

Patient-reported outcomes and considerations in the management of COPD: focus on aclidinium

Chronic obstructive pulmonary disease (COPD) is a complex heterogeneous disease, in which several factors combine to give the final clinical expression. Both early and more recent studies have shown that forced expiratory volume in one second (FEV1), despite being an extremely important parameter to predict the progression of the disease, is a poor surrogate marker for symptoms perception. Accordingly, patient-reported outcomes (PROs) have gained popularity as a measure of the impact of treatment from the patients' perspective, since they represent the individuals' perception of their health status, beyond any physiological limitations. Several such PROs, therefore, are currently included in multidimensional COPD evaluation. This multidimensional approach helps identify different patient types and individualize, up to a certain point, pharmacological treatment. In this multidimensional approach it is important to highlight the importance of long-acting bronchodilators in COPD treatment strategies. Long-acting bronchodilators are cost-effective and have been shown to achieve the greatest functional and clinical improvements in COPD. As a result, long-acting bronchodilators are now the main pharmacological treatment for COPD at all stages of the disease. Until recently, tiotropium was the leading bronchodilator for the treatment of COPD. The clinical development of this medication, unprecedented in inhaled therapy, involved tens of thousands of patients and yielded consistent outcomes in terms of lung function, symptoms, quality of life, exacerbations, and prognosis. However, new long-acting bronchodilators have recently been developed or are currently under development. In this review, we evaluate the effects of aclidinium bromide, a novel long-acting bronchodilator, on PROs in COPD. Aclidinium is a novel long-acting muscarinic antagonist with a good safety profile for the treatment of COPD, and has proven efficacy in both objective functional measurements and PROs. Comparison studies with tiotropium have shown it to have similar lung function improvement and a similar impact on PROs, including quality of life or symptom perception.

A re-evaluation of the role of inhaled corticosteroids in the management of patients with chronic obstructive pulmonary disease

INTRODUCTION

Inhaled corticosteroids (ICS) (in fixed combinations with long-acting β2-agonists [LABAs]) are frequently prescribed for patients with chronic obstructive pulmonary disease (COPD), outside their labeled indications and recommended treatment strategies and guidelines, despite having the potential to cause significant side effects.

AREAS COVERED

Although the existence of asthma in patients with asthma-COPD overlap syndrome (ACOS) clearly supports the use of anti-inflammatory treatment (typically an ICS/LABA combination, as ICS monotherapy is usually not indicated for COPD), the current level of ICS/LABA use is not consistent with the prevalence of ACOS in the COPD population. Data have recently become available showing the comparative efficacy of fixed bronchodilator combinations (long-acting muscarinic antagonist [LAMA]/LABA with ICS/LABA combinations). Additionally, new information has emerged on ICS withdrawal without increased risk of exacerbations, under cover of effective bronchodilation.

EXPERT OPINION

For patients with COPD who do not have ACOS, a LAMA/LABA combination may be an appropriate starting therapy, apart from those with mild disease who can be managed with a single long-acting bronchodilator. Patients who remain symptomatic or present with exacerbations despite effectively delivered LAMA/LABA treatment may require additional drug therapy, such as ICS or phosphodiesterase-4 inhibitors. When prescribing an ICS/LABA, the risk:benefit ratio should be considered in individual patients.

Impact of coexisting pulmonary diseases on survival of patients with lung adenocarcinoma: a STROBE-compliant article

Asthma, chronic obstructive pulmonary disease (COPD), and pulmonary tuberculosis (TB) are common pulmonary diseases associated with lung cancer. Besides, smoking is more prevalent in Taiwanese men. This study evaluated gender disparities in coexisting pulmonary diseases on survival of patients with lung adenocarcinoma. Patients newly diagnosed with lung cancer between 2003 and 2008 were identified from Taiwan National Health Insurance Research Database. Cases with lung adenocarcinoma were further confirmed using the Cancer Registry Database and followed up until the end of 2010. Cox proportional hazard regression was used to calculate the hazard ratio (HR) of coexisting asthma, COPD, and/or TB to estimate all-cause mortality risk. During the study period, 13,399 cases of lung adenocarcinoma were identified. The HRs of adenocarcinoma in men and women were 1.20 (95% confidence interval [CI], 1.10-1.30) and 1.05 (95% CI, 0.95-1.16), respectively, for individuals with asthma, 1.32 (95% CI, 1.16-1.51) and 0.97 (95% CI, 0.89-1.05), respectively, for COPD, and 0.99 (95% CI, 0.93-1.06) and 1.06 (95% CI, 0.86-1.32), respectively, for individuals with TB. Specifically, among men with coexisting pulmonary diseases, the HRs were 1.63 (95% CI, 1.25-2.13), 1.31 (95% CI, 1.08-1.59), and 1.23 (95% CI, 1.11-1.36) for individuals with asthma + COPD + TB, asthma + COPD, and COPD + TB, respectively. However, there was no increase risk of mortality among women with coexisting pulmonary diseases. Coexisting pulmonary diseases are at an elevated risk of mortality among male patients with lung adenocarcinoma. Such patients deserve greater attention while undergoing cancer treatment.

Clinical characteristics of COPD syndrome: A 6-year follow-up study of adult smokers

BACKGROUND

There is little quantitative information about the development of chronic obstructive pulmonary disease (COPD) among adult smokers and of what happens to patients who have already developed COPD.

OBJECTIVES

To examine the development and performance of COPD status over time, and the clinical characteristics of new COPD cases according to the Global Initiative for Chronic Obstructive Lung Disease (GOLD) 2007 and 2011 classifications.

METHODS

Healthy asymptomatic smokers were recruited through newspaper announcements. They filled in questionnaires and had an individualized assessment of their health history during all three visits (visit 1, visit 2 after three years, visit 3 after six years).

RESULTS

Of the eligible 621 heavy smokers, 572 attended visit 2. A total of 513 subjects completed the 6-year follow-up examination. According to GOLD 2007, COPD was present in 22.8% (n = 117) of these smokers. The severity of COPD changed during the years of follow-up. Furthermore, health status and prevalence of chronic respiratory symptoms both in the smokers with normal lung function and in the COPD groups varied over the time period.

CONCLUSIONS

GOLD 2011 recognized the complex patient subgroups better than GOLD 2007. Variability in chronic symptoms or in health status correlated poorly with the severity of airway limitation.

Different durations of corticosteroid therapy for exacerbations of chronic obstructive pulmonary disease

BACKGROUND

Current guidelines recommend that patients with acute exacerbations of chronic obstructive pulmonary disease (COPD) should be treated with systemic corticosteroid for seven to 14 days. Intermittent systemic corticosteroid use is cumulatively associated with adverse effects such as osteoporosis, hyperglycaemia and muscle weakness. Shorter treatment could reduce adverse effects.

OBJECTIVES

To compare the efficacy of short-duration (seven or fewer days) and conventional longer-duration (longer than seven days) systemic corticosteroid treatment of adults with acute exacerbations of COPD.

SEARCH METHODS

Searches were carried out using the Cochrane Airways Group Specialised Register of Trials, MEDLINE and CENTRAL (Cochrane Central Register of Controlled Trials) up to June 2014 and ongoing trials registers up to July 2014.

SELECTION CRITERIA

Randomised controlled trials comparing different durations of systemic corticosteroid defined as short (i.e. seven or fewer days) or longer (i.e. longer than seven days). Other interventions-bronchodilators and antibiotics-were standardised. Studies with participants requiring assisted ventilation were excluded.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures as expected by The Cochrane Collaboration.

MAIN RESULTS

Eight studies with 582 participants met the inclusion criteria, of which five studies conducted in hospitals with 519 participants (range 28 to 296) contributed to the meta-analysis. Mean ages of study participants were 65 to 73 years, the proportion of male participants varied (58% to 84%) and COPD was classified as severe or very severe. Corticosteroid treatment was given at equivalent daily doses for three to seven days for short-duration treatment and for 10 to 15 days for longer-duration treatment. Five studies administered oral prednisolone (30 mg in four, tapered in one), and two studies provided intravenous corticosteroid treatment. Studies contributing to the meta-analysis were at low risk of selection, performance, detection and attrition bias. In four studies we did not find a difference in risk of treatment failure between short-duration and longer-duration systemic corticosteroid treatment (n = 457; odds ratio (OR) 0.72, 95% confidence interval (CI) 0.36 to 1.46)), which was equivalent to 22 fewer per 1000 for short-duration treatment (95% CI 51 fewer to 34 more). No difference in risk of relapse (a new event) was observed between short-duration and longer-duration systemic corticosteroid treatment (n = 457; OR 1.04, 95% CI 0.70 to 1.56), which was equivalent to nine fewer per 1000 for short-duration treatment (95% CI 68 fewer to 100 more). Time to the next COPD exacerbation did not differ in one large study that was powered to detect non-inferiority and compared five days versus 14 days of systemic corticosteroid treatment (n = 311; hazard ratio 0.95, 95% CI 0.66 to 1.37). In five studies no difference in the likelihood of an adverse event was found between short-duration and longer-duration systemic corticosteroid treatment (n = 503; OR 0.89, 95% CI 0.46 to 1.69, or nine fewer per 1000 (95% CI 44 fewer to 51 more)). Length of hospital stay (n = 421; mean difference (MD) -0.61 days, 95% CI -1.51 to 0.28) and lung function at the end of treatment (n = 185; MD FEV1 -0.04 L; 95% CI -0.19 to 0.10) did not differ between short-duration and longer-duration treatment.

AUTHORS' CONCLUSIONS

Information from a new large study has increased our confidence that five days of oral corticosteroids is likely to be sufficient for treatment of adults with acute exacerbations of COPD, and this review suggests that the likelihood is low that shorter courses of systemic corticosteroids (of around five days) lead to worse outcomes than are seen with longer (10 to 14 days) courses. We graded most available evidence as moderate in quality because of imprecision; further research may have an important impact on our confidence in the estimates of effect or may change the estimates. The studies in this review did not include people with mild or moderate COPD; further studies comparing short-duration systemic corticosteroid versus conventional longer-duration systemic corticosteroid for treatment of adults with acute exacerbations of COPD are required.

Asthma-chronic obstructive pulmonary disease overlap syndrome in Poland. Findings of an epidemiological study

Introduction

Recent years have seen an increased interest in asthma-chronic obstructive pulmonary disease (COPD) overlap syndrome (ACOS).

Aim

In 2012, Takeda Polska conducted a non-interventional epidemiological study aimed at identifying the typical phenotype of ACOS patients receiving pulmonary care.

Material and methods

The study enrolled a total of 12,103 of smoking patients above 45 years of age (mean age: 61.5 years; mean duration of smoking: 28.4 pack-years). A total of 68.6% of patients represented the frequent-exacerbation phenotype (mean number of exacerbations during 12 months: 2.11), and 56.4% of patients from the group comprising 12,103 participants were hospitalized at least once during their lifetime due to a respiratory system disease (mean number: 3.82 ±3.76).

Results

The most commonly found asthma symptoms included paroxysmal dyspnoea with wheezing, and good response to inhaled steroids. The most frequently identified COPD-associated symptoms were: long-lasting reduction in forced expiratory volume in 1 s (FEV₁) (< 80% after administering a bronchodilator) and chronic productive cough. Eighty-five percent of patients were diagnosed with concomitant diseases, predominantly arterial hypertension (62.9%) and metabolic diseases (metabolic syndrome, obesity, type 2 diabetes – 46.4% in total).

Conclusions

A clinically severe course of ACOS and the presence of concomitant diseases should be regarded as factors justifying an individual selection of inhalation therapy which specifically takes into account anti-inflammatory treatment and patient safety.

The coexistence of common pulmonary diseases on the histologic type of lung cancer in both genders in Taiwan: a STROBE-compliant article

Effects of pulmonary diseases [asthma, chronic obstructive pulmonary disease (COPD), and lung tuberculosis (TB)] on subsequent lung cancer development have been reported. However, whether patients with coexisting pulmonary diseases are at greater risk of developing various histologic types of lung cancer remains elusive. Patients newly diagnosed with lung cancer between 2004 and 2008 were identified from National Health Insurance Research Database (Taiwan). The histologic types of lung cancer were further confirmed using Taiwan Cancer Registry Database. Cox proportional hazard regression was used to calculate the hazard ratio (HR) of coexisting asthma, COPD and/or TB to estimate lung cancer risk by histologic type. During the study period, 32,759 cases of lung cancer were identified from 15,219,024 residents age 20 years and older, who were free from the disease before 2003. Coexisting pulmonary diseases showed stronger association with lung cancer than specific lung disorders. Specifically, among men, the HRs for squamous cell carcinoma (SqCC) were 3.98 (95% CI, 3.22-4.93), 2.68 (95% CI, 2.45-2.93), and 2.57 (95% CI, 2.10-3.13) for individuals with asthma+COPD+TB, asthma+COPD, and COPD+TB, respectively. Among women, the HRs for SqCC were 3.64 (95% CI, 1.88-7.05), 3.35 (95% CI, 1.59-7.07), and 2.21 (95% CI, 1.66-2.94) for individuals with TB, COPD+TB, and asthma+COPD, respectively. Adenocarcinoma HRs for men and women were 2.00 (95% CI, 1.54-2.60) and 2.82 (95% CI, 1.97-4.04) for individuals with asthma+COPD+TB, 2.28 (95% CI, 1.91-2.73) and 2.16 (95% CI, 1.57-2.95) for COPD+TB, and 1.76 (95% CI, 1.04-2.97) and 2.04 (95% CI, 1.02-4.09) for individuals with asthma+TB. Specifically, small cell carcinoma (SmCC) HRs among men were 3.65 (95% CI, 1.97-6.80), 2.20 (95% CI, 1.45-3.36), and 2.14 (95% CI, 1.86-2.47) for those with asthma+TB, asthma+COPD+TB, and asthma+ COPD, respectively. Among women, the HRs of SmCC were 8.97 (95% CI, 3.31-24.28), 3.94 (95% CI, 1.25-12.35) and 3.33 (95% CI, 2.23-4.97) for those with asthma+COPD+TB, COPD+TB, and asthma+COPD, respectively. Patients with coexistence of pulmonary diseases were more susceptible to lung cancer. Affected persons deserve greater attention while undergoing cancer screening.

Genetics of allergic diseases

Genome-wide association studies (GWAS) have been employed in the field of allergic disease, and significant associations have been published for nearly 100 asthma genes/loci. An outcome of GWAS in allergic disease has been the formation of national and international collaborations leading to consortia meta-analyses, and an appreciation for the specificity of genetic associations to sub-phenotypes of allergic disease. Molecular genetics has undergone a technological revolution, leading to next-generation sequencing strategies that are increasingly employed to hone in on the causal variants associated with allergic diseases. Unmet needs include the inclusion of diverse cohorts and strategies for managing big data.

Integrative genomics of chronic obstructive pulmonary disease

Chronic obstructive pulmonary disease (COPD) is a complex disease with both environmental and genetic determinants, the most important of which is cigarette smoking. There is marked heterogeneity in the development of COPD among persons with similar cigarette smoking histories, which is likely partially explained by genetic variation. Genomic approaches such as genomewide association studies and gene expression studies have been used to discover genes and molecular pathways involved in COPD pathogenesis; however, these "first generation" omics studies have limitations. Integrative genomic studies are emerging which can combine genomic datasets to further examine the molecular underpinnings of COPD. Future research in COPD genetics will likely use network-based approaches to integrate multiple genomic data types in order to model the complex molecular interactions involved in COPD pathogenesis. This article reviews the genomic research to date and offers a vision for the future of integrative genomic research in COPD.