Evaluation of COPD Longitudinally to Identify Predictive Surrogate End-points (ECLIPSE)

Identifying a Deletion Affecting Total Lung Capacity Among Subjects in the COPDGene Study Cohort

Chronic obstructive pulmonary disease (COPD) is a progressive disease with both environmental and genetic risk factors. Genome-wide association studies (GWAS) have identified multiple genomic regions influencing risk of COPD. To thoroughly investigate the genetic etiology of COPD, however, it is also important to explore the role of copy number variants (CNVs) because the presence of structural variants can alter gene expression and can be causal for some diseases. Here, we investigated effects of polymorphic CNVs on quantitative measures of pulmonary function and chest computed tomography (CT) phenotypes among subjects enrolled in COPDGene, a multisite study. COPDGene subjects consist of roughly one-third African American (AA) and two-thirds non-Hispanic white adult smokers (with or without COPD). We estimated CNVs using PennCNV on 9,076 COPDGene subjects using Illumina's Omni-Express genome-wide marker array. We tested for association between polymorphic CNV components (defined as disjoint intervals of copy number regions) for several quantitative phenotypes associated with COPD within each racial group. Among the AAs, we identified a polymorphic CNV on chromosome 5q35.2 located between two genes (FAM153B and SIMK1, but also harboring several pseudo-genes) giving genome-wide significance in tests of association with total lung capacity (TLCCT ) as measured by chest CT scans. This is the first study of genome-wide association tests of polymorphic CNVs and TLCCT . Although the ARIC cohort did not have the phenotype of TLCCT , we found similar counts of CNV deletions and amplifications among AA and European subjects in this second cohort.

A genome-wide association study identifies risk loci for spirometric measures among smokers of European and African ancestry

BACKGROUND

Pulmonary function decline is a major contributor to morbidity and mortality among smokers. Post bronchodilator FEV1 and FEV1/FVC ratio are considered the standard assessment of airflow obstruction. We performed a genome-wide association study (GWAS) in 9919 current and former smokers in the COPDGene study (6659 non-Hispanic Whites [NHW] and 3260 African Americans [AA]) to identify associations with spirometric measures (post-bronchodilator FEV1 and FEV1/FVC). We also conducted meta-analysis of FEV1 and FEV1/FVC GWAS in the COPDGene, ECLIPSE, and GenKOLS cohorts (total n = 13,532).

RESULTS

Among NHW in the COPDGene cohort, both measures of pulmonary function were significantly associated with SNPs at the 15q25 locus [containing CHRNA3/5, AGPHD1, IREB2, CHRNB4] (lowest p-value = 2.17 × 10(-11)), and FEV1/FVC was associated with a genomic region on chromosome 4 [upstream of HHIP] (lowest p-value = 5.94 × 10(-10)); both regions have been previously associated with COPD. For the meta-analysis, in addition to confirming associations to the regions near CHRNA3/5 and HHIP, genome-wide significant associations were identified for FEV1 on chromosome 1 [TGFB2] (p-value = 8.99 × 10(-9)), 9 [DBH] (p-value = 9.69 × 10(-9)) and 19 [CYP2A6/7] (p-value = 3.49 × 10(-8)) and for FEV1/FVC on chromosome 1 [TGFB2] (p-value = 8.99 × 10(-9)), 4 [FAM13A] (p-value = 3.88 × 10(-12)), 11 [MMP3/12] (p-value = 3.29 × 10(-10)) and 14 [RIN3] (p-value = 5.64 × 10(-9)).

CONCLUSIONS

In a large genome-wide association study of lung function in smokers, we found genome-wide significant associations at several previously described loci with lung function or COPD. We additionally identified a novel genome-wide significant locus with FEV1 on chromosome 9 [DBH] in a meta-analysis of three study populations.

Identification of five chronic obstructive pulmonary disease subgroups with different prognoses in the ECLIPSE cohort using cluster analysis

RATIONALE

Chronic obstructive pulmonary disease (COPD) is a heterogeneous disease that likely includes clinically relevant subgroups.

OBJECTIVES

To identify subgroups of COPD in ECLIPSE (Evaluation of COPD Longitudinally to Identify Predictive Surrogate Endpoints) subjects using cluster analysis and to assess clinically meaningful outcomes of the clusters during 3 years of longitudinal follow-up.

METHODS

Factor analysis was used to reduce 41 variables determined at recruitment in 2,164 patients with COPD to 13 main factors, and the variables with the highest loading were used for cluster analysis. Clusters were evaluated for their relationship with clinically meaningful outcomes during 3 years of follow-up. The relationships among clinical parameters were evaluated within clusters.

MEASUREMENTS AND MAIN RESULTS

Five subgroups were distinguished using cross-sectional clinical features. These groups differed regarding outcomes. Cluster A included patients with milder disease and had fewer deaths and hospitalizations. Cluster B had less systemic inflammation at baseline but had notable changes in health status and emphysema extent. Cluster C had many comorbidities, evidence of systemic inflammation, and the highest mortality. Cluster D had low FEV1, severe emphysema, and the highest exacerbation and COPD hospitalization rate. Cluster E was intermediate for most variables and may represent a mixed group that includes further clusters. The relationships among clinical variables within clusters differed from that in the entire COPD population.

CONCLUSIONS

Cluster analysis using baseline data in ECLIPSE identified five COPD subgroups that differ in outcomes and inflammatory biomarkers and show different relationships between clinical parameters, suggesting the clusters represent clinically and biologically different subtypes of COPD.

The Effect of Statins on Blood Gene Expression in COPD

BACKGROUND

COPD is currently the fourth leading cause of death worldwide. Statins are lipid lowering agents with documented cardiovascular benefits. Observational studies have shown that statins may have a beneficial role in COPD. The impact of statins on blood gene expression from COPD patients is largely unknown.

OBJECTIVE

Identify blood gene signature associated with statin use in COPD patients, and the pathways underpinning this signature that could explain any potential benefits in COPD.

METHODS

Whole blood gene expression was measured on 168 statin users and 451 non-users from the ECLIPSE study using the Affymetrix Human Gene 1.1 ST microarray chips. Factor Analysis for Robust Microarray Summarization (FARMS) was used to process the expression data. Differential gene expression analysis was undertaken using the Linear Models for Microarray data (Limma) package adjusting for propensity score and surrogate variables. Similarity of the expression signal with published gene expression profiles was performed in ProfileChaser.

RESULTS

25 genes were differentially expressed between statin users and non-users at an FDR of 10%, including LDLR, CXCR2, SC4MOL, FAM108A1, IFI35, FRYL, ABCG1, MYLIP, and DHCR24. The 25 genes were significantly enriched in cholesterol homeostasis and metabolism pathways. The resulting gene signature showed correlation with Huntington's disease, Parkinson's disease and acute myeloid leukemia gene signatures.

CONCLUSION

The blood gene signature of statins' use in COPD patients was enriched in cholesterol homeostasis pathways. Further studies are needed to delineate the role of these pathways in lung biology.

Statistical Modeling of Disease Progression for Chronic Obstructive Pulmonary Disease Using Data from the ECLIPSE Study

BACKGROUND

To develop statistical models predicting disease progression and outcomes in chronic obstructive pulmonary disease (COPD), using data from ECLIPSE, a large, observational study of current and former smokers with COPD.

METHODS

Based on a conceptual model of COPD disease progression and data from 2164 patients, associations were made between baseline characteristics, COPD disease progression attributes (exacerbations, lung function, exercise capacity, and symptoms), health-related quality of life (HRQoL), and survival. Linear and nonlinear functional forms of random intercept models were used to characterize these relationships. Endogeneity was addressed by time-lagging variables in the regression models.

RESULTS

At the 5% significance level, an exacerbation history in the year before baseline was associated with increased risk of future exacerbations (moderate: +125.8%; severe: +89.2%) and decline in lung function (forced expiratory volume in 1 second [FEV₁]) (-94.20 mL per year). Each 1% increase in FEV₁ % predicted was associated with decreased risk of exacerbations (moderate: -1.1%; severe: -3.0%) and increased 6-minute walk test distance (6MWD) (+1.5 m). Increases in baseline exercise capacity (6MWD, per meter) were associated with slightly increased risk of moderate exacerbations (+0.04%) and increased FEV₁ (+0.62 mL). Symptoms (dyspnea, cough, and/or sputum) were associated with an increased risk of moderate exacerbations (+13.4% to +31.1%), and baseline dyspnea (modified Medical Research Council score ≥2 v. <2) was associated with lower FEV₁ (-112.3 mL).

CONCLUSIONS

A series of linked statistical regression equations have been developed to express associations between indicators of COPD disease severity and HRQoL and survival. These can be used to represent disease progression, for example, in new economic models of COPD.

8th international conference on management and rehabilitation of chronic respiratory failure: the long summaries – part 1

This paper summarizes the Part 1 of the proceedings of the 8^th International Conference on Management and Rehabilitation of Chronic Respiratory Failure, held in Pescara, Italy, on 7 and 8 May, 2015. It summarizes the contributions from numerous experts in the field of chronic respiratory disease and chronic respiratory failure. The outline follows the temporal sequence of presentations.

This paper (Part 1) includes sections regarding: Advances in Asthma and COPD Therapy (Novel Therapeutic Targets for Asthma: Proteinases, Blood Biomarker Changes in COPD Patients); The problem of Hospital Re-Admission following Discharge after the COPD Exacerbation (Characteristics of the Hospitalized COPD Patient, Reducing Hospital Readmissions Following COPD Exacerbation).

Biomarkers for precision medicine in airways disease

Chronic obstructive pulmonary disease (COPD) is a complex clinical entity. In contrast to previously limited diagnostic definitions, it is now apparent that COPD is a clinically and biologically heterogeneous disease process, overlapping with other airways diseases like chronic asthma. As such, symptomatic response to current standard treatment practices is variable. New clinical guidelines have been altered to reflect this, with the inclusion of symptoms and risk factors in diagnostic and management algorithms. However, as our understanding of COPD pathophysiology deepens, many novel physiological, cellular, proteomic, and genetic markers have been identified. Several have been observed to be independently predictive of distinct clinical disease patterns, which at present are not illustrated by conventional measurements of lung impairment. The potential use of these predictive biomarkers to stratify this diverse patient population could transform the care we offer. We should aim for precision medicine to optimize diagnosis and treatment choices and to monitor and improve clinical outcomes in this disease.

A Genome-Wide Association Study of Emphysema and Airway Quantitative Imaging Phenotypes

RATIONALE

Chronic obstructive pulmonary disease (COPD) is defined by the presence of airflow limitation on spirometry, yet subjects with COPD can have marked differences in computed tomography imaging. These differences may be driven by genetic factors. We hypothesized that a genome-wide association study (GWAS) of quantitative imaging would identify loci not previously identified in analyses of COPD or spirometry. In addition, we sought to determine whether previously described genome-wide significant COPD and spirometric loci were associated with emphysema or airway phenotypes.

OBJECTIVES

To identify genetic determinants of quantitative imaging phenotypes.

METHODS

We performed a GWAS on two quantitative emphysema and two quantitative airway imaging phenotypes in the COPDGene (non-Hispanic white and African American), ECLIPSE (Evaluation of COPD Longitudinally to Identify Predictive Surrogate Endpoints), NETT (National Emphysema Treatment Trial), and GenKOLS (Genetics of COPD, Norway) studies and on percentage gas trapping in COPDGene. We also examined specific loci reported as genome-wide significant for spirometric phenotypes related to airflow limitation or COPD.

MEASUREMENTS AND MAIN RESULTS

The total sample size across all cohorts was 12,031, of whom 9,338 were from COPDGene. We identified five loci associated with emphysema-related phenotypes, one with airway-related phenotypes, and two with gas trapping. These loci included previously reported associations, including the HHIP, 15q25, and AGER loci, as well as novel associations near SERPINA10 and DLC1. All previously reported COPD and a significant number of spirometric GWAS loci were at least nominally (P < 0.05) associated with either emphysema or airway phenotypes.

CONCLUSIONS

Genome-wide analysis may identify novel risk factors for quantitative imaging characteristics in COPD and also identify imaging features associated with previously identified lung function loci.

Bioregulatory systems medicine: an innovative approach to integrating the science of molecular networks, inflammation, and systems biology with the patient's autoregulatory capacity?

Bioregulatory systems medicine (BrSM) is a paradigm that aims to advance current medical practices. The basic scientific and clinical tenets of this approach embrace an interconnected picture of human health, supported largely by recent advances in systems biology and genomics, and focus on the implications of multi-scale interconnectivity for improving therapeutic approaches to disease. This article introduces the formal incorporation of these scientific and clinical elements into a cohesive theoretical model of the BrSM approach. The authors review this integrated body of knowledge and discuss how the emergent conceptual model offers the medical field a new avenue for extending the armamentarium of current treatment and healthcare, with the ultimate goal of improving population health.

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.

Does Improving Exercise Capacity and Daily Activity Represent the Holistic Perspective of a New COPD Approach?

In COPD patients a reduced daily activity has been well documented, resulting from both respiratory and non-respiratory manifestations of the disease. An evaluation by multisensory armband has confirmed that daily physical activity is mainly associated with dynamic hyperinflation, regardless of COPD severity. This aspect is crucial, since exercise capacity is closely correlated to life expectancy. Notwithstanding the causal key role of lung impairment in the patient's symptoms, some authors have suggested that other factors, such as systemic inflammation and co-morbidities, have an important role, particularly as mortality risk factors. Many studies suggest the efficacy of bronchodilators and rehabilitation in improving exercise capacity, and, speaking in terms of daily life, in increasing the number of days in which patients are able to perform their usual activities. On this evidence, the first aim in the management of COPD should be to improve exercise capacity and daily activity since these outcomes have direct effects on patients' quality of life, co-morbidities (heart and metabolic diseases), and prognosis. Thus, improving physical activity represents a modern approach aimed at dealing with both pulmonary and systemic manifestations of the disease. It is however worth of notice to remember that in patients affected by COPD the relationship between the improvement of "potential" exercise capacity and daily physical activity has been found to be only moderate to weak. Obtaining a significant behavior modification with regard to daily physical activity, together with the optimization of therapy thus represents currently the true challenge.

Survey to determine the efficacy and safety of guideline-based pharmacological therapy for chronic obstructive pulmonary disease patients not previously receiving maintenance treatment

OBJECTIVE

To investigate the potential beneficial effects of guideline-based pharmacological therapy on pulmonary function and quality of life (QOL) in Japanese chronic obstructive pulmonary disease (COPD) patients without prior treatment.

RESEARCH DESIGN AND METHODS

Multicenter survey, open-label study of 49 Japanese COPD patients aged ≥ 40 years; outpatients with >10 pack years of smoking history; ratio of forced expiratory volume in 1 s (FEV1)/forced vital capacity (FVC) < 70%; predicted FEV1 < 80%; treated with bronchodilators and/or inhaled corticosteroids as maintenance therapy until week 48.

MAIN OUTCOME MEASURES

The primary endpoint was change in pulmonary function (trough FEV1, trough FVC); secondary endpoints were QOL and physical activity at 48 weeks after initiation of therapy.

RESULTS

Airway reversibility was confirmed in untreated patients. Significant changes over time were not observed for FEV1 and FVC, indicating lung function at initiation of treatment was maintained during the observation period. COPD assessment test scores showed statistical and clinical improvements. Cough, sputum, breathlessness, and shortness of breath were significantly improved.

CONCLUSIONS

Lung function and QOL of untreated Japanese COPD patients improved and improvements were maintained by performing a therapeutic intervention that conformed to published guidelines.

COPD: Do Imaging Measurements of Emphysema and Airway Disease Explain Symptoms and Exercise Capacity?

PURPOSE

To determine the role of imaging measurements of emphysema and airway disease in determining chronic obstructive pulmonary disease (COPD) symptoms and exercise limitation in patients with COPD, particularly in patients with mild-to-moderate disease.

MATERIALS AND METHODS

Participants (n = 116) with Global Initiative for Chronic Obstructive Lung Disease (GOLD) grade U (unclassified) or grade I-IV COPD provided informed consent to an ethics board-approved HIPAA-compliant protocol and underwent spirometry and plethysmography, completed the St George's Respiratory Questionnaire (SGRQ), completed a 6-minute walk test for the 6-minute walk distance (6MWD), and underwent hyperpolarized helium 3 ((3)He) magnetic resonance (MR) imaging and computed tomography (CT). Emphysema was estimated by using the MR imaging apparent diffusion coefficient (ADC) and the relative area of the CT attenuation histogram with attenuation of -950 HU or less (RA950). Airway disease was measured by using the CT airway wall thickness of airways with an internal perimeter of 10 mm and total airway count. Ventilation defect percentage at (3)He MR imaging was used to measure ventilation. Multivariable regression models for the 6MWD and SGRQ symptom subscore were used to evaluate the relationships between physiologic and imaging measurements.

RESULTS

Multivariate modeling for the 6MWD in 80 patients with GOLD grade U-II COPD showed that ADC (β = 0.34, P = .04), diffusing capacity of the lung for carbon monoxide (β = 0.60, P = .0008), and residual volume/total lung capacity (β = -0.26, P = .02) were significant variables, while forced expiratory volume in 1 second (FEV1) and airway disease measurements were not. In 36 patients with GOLD grade III or IV disease, FEV1 (β = 0.48, P = .01) was the only significant contributor in a multivariate model for 6MWD. MR imaging emphysema measurements also made the greatest relative contribution to symptoms in patients with milder (GOLD grade U-II) COPD (ADC: β = 0.60, P = .005; RA950: β = -0.52, P = .02; FEV1: β = -0.45, P = .0002) and in grade III or IV disease (ADC: β = 0.95, P = .01; RA950: β = -0.62, P = .07; airway count: β = -0.49, P = .01).

CONCLUSION

In patients with mild-to-moderate COPD, MR imaging emphysema measurements played a dominant role in the expression of exercise limitation, while both CT and MR imaging measurements of emphysema explained symptoms.

Prognostic value of variables derived from the six-minute walk test in patients with COPD: Results from the ECLIPSE study

In addition to the six-min walk distance (6 MWD), other six-min walk test (6 MWT) derived variables, such as mean walk-speed (6MWSpeed), 6-min walk-work (6 MWW), distance-saturation product (DSP), exercise-induced oxygen desaturation (EID), and unintended stops may be useful for the prediction of mortality and hospitalization in patients with chronic obstructive pulmonary disease (COPD). We studied the association between 6 MWT-derived variables and mortality as well as hospitalization in COPD patients and compared it with the BODE index. A three-year prospective study (ECLIPSE) to evaluate the prognostic value of 6 MWT-derived variables in 2010 COPD patients. Cox's proportional-hazard regressions were performed to estimate 3-year mortality and hospitalization. During the follow-up, 193 subjects died and 622 were hospitalized. An adjusted Cox's regression model of hazard ratio [HR] for impaired 6 MWT-derived variables was significant referring to: mortality (6 MWD ≤334 m [2.30], 6MWSpeed ≤0.9 m/sec [2.15], 6 MWW ≤20000 m kg [2.17], DSP ≤290 m% [2.70], EID ≤88% [1.75], unintended stops [1.99]; and hospitalization (6 MWW ≤27000 m kg [1.23], EID ≤88% [1.25], BODE index ≥3 points [1.40]; all p ≤ 0.05). The 6 MWT-derived variables have an additional predictive value of mortality in patients with COPD. The 6 MWW, EID and the BODE index refine the prognosis of hospitalization.

Associations between gastro-oesophageal reflux, its management and exacerbations of chronic obstructive pulmonary disease

AIM

To determine factors, overall and by sex, associated with self-reported gastro-oesophageal reflux disease (GORD) in chronic obstructive pulmonary disease (COPD) patients, and to evaluate relationships between GORD, its modification by acid suppression medications (Proton Pump Inhibitors [PPI]/histamine-2 receptor antagonists [H2RA]) and exacerbations of COPD and mortality.

METHODS

Logistic regression was used to determine factors associated with GORD; Cox proportional hazards models were used to calculate adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) for GORD and risk of exacerbation and death.

RESULTS

Among 2135 COPD patients from the ECLIPSE cohort, 547 patients self-reported GORD, with female preponderance; 237 were taking PPI/H2RA. Risk factors for GORD did not differ by sex. When compared to patients who did not report GORD or use of PPI/H2RA, patients with GORD and taking PPI/H2RA had a significantly increased risk of exacerbation (HR = 1.58, 95%CI = 1.35-1.86); risk was also increased for patients reporting GORD only or PPI/H2RA use only (HR = 1.21 [1.04-1.40] and 1.33 [1.08-1.65], respectively). Similar findings were observed for risk of hospitalised exacerbation. GORD was not associated with mortality.

CONCLUSION

GORD in COPD patients is highly prevalent, and risk factors did not differ by sex. Use of PPI/H2RA and self-reported GORD were associated with increased risk of moderate-to-severe and hospitalised exacerbations.

Hospitalized exacerbations of COPD: risk factors and outcomes in the ECLIPSE cohort

OBJECTIVE

Exacerbations of COPD requiring hospital admission have important clinical and societal implications. We sought to investigate the incidence, recurrence, risk factors, and mortality of patients with COPD exacerbations requiring hospital admission compared with those without hospital admission during 3-year follow-up. Patients with COPD (N = 2,138) were identified from the Evaluation of COPD Longitudinally to Identify Predictive Surrogate Endpoints (ECLIPSE) observational cohort.

METHODS

An analysis of time to first event of hospital admission was performed using Kaplan-Meier curves and Cox proportional hazard regression adjusting for possible confounders.

RESULTS

Of the 2,138 patients, 670 (31%) reported a total of 1,452 COPD exacerbations requiring hospital admission during the study period; 313 patients (15%) reported multiple events. A prior history of exacerbation of COPD requiring hospital admission was the factor associated with the highest risk of a new hospitalization for exacerbation (hazard ratio, 2.71; 95% CI, 2.24-3.29; P < .001). Other risk factors included more severe airflow limitation, poorer health status, older age, radiologic evidence of emphysema, and higher WBC count. Having been hospitalized for exacerbation significantly increased the risk of mortality (P < .001).

CONCLUSIONS

Exacerbations of COPD requiring hospital admission occur across all stages of airflow limitation and are a significant prognostic factor of reduced survival across all COPD stages. Patients with COPD at a high risk for hospitalization can be identified by their past history for similar events, and other factors, including the severity of airflow limitation, poor health status, age, presence of emphysema, and leukocytosis.

TRIAL REGISTRY

ClinicalTrials.gov; No.: NCT00292552; URL: www.clinicaltrials.gov.

Evaluation of the COPD Assessment Test and GOLD patient types: a cross-sectional analysis

Background

The COPD Assessment Test (CAT) has been recently developed to quantify COPD impact in routine practice. However, no relationship with other measures in the Global Initiative for Obstructive Lung Disease (GOLD) strategy has been evaluated. The present study aimed to evaluate the relationship of the CAT with other GOLD multidimensional axes, patient types, and the number of comorbidities.

Methods

This was a cross-sectional analysis of the Clinical presentation, diagnosis, and course of chronic obstructive pulmonary disease (On-Sint) study. The CAT score was administered to all participants at the inclusion visit. A GOLD 2011 strategy consisting of modified Medical Research Council scale (MRC) scores was devised to study the relationship between the CAT, and GOLD 2011 axes and patient types. The relationship with comorbidities was assessed using the Charlson comorbidity index, grouped as zero, one to two, and three or more.

Results

The CAT questionnaire was completed by 1,212 patients with COPD. The CAT maintained a relationship with all the three axes, with a ceiling effect for dyspnea and no distinction between mild and moderate functional impairment. The CAT score increased across GOLD 2011 patient types A–D, with similar scores for types B and C. Within each GOLD 2011 patient type, there was a considerably wide distribution of CAT values.

Conclusion

Our study indicates a correlation between CAT and the GOLD 2011 classification axes as well as the number of comorbidities. The CAT score can help clinicians, as a complementary tool to evaluate patients with COPD within the different GOLD patient types.

Correlation Between Emphysema and Lung Function in Healthy Smokers and Smokers With COPD

Background: Emphysema is an important component of COPD; however, in previous studies of the correlation between airflow limitation (AFL) and computed tomography (CT) lung density as a surrogate for emphysema has varied. We hypothesised a good correlation between lung function (forced expiratory volume in first second [FEV₁]) and emphysema (15^th percentile density [PD15]) and that this correlation also exists between loss of lung tissue and decline in lung function even within the time frame of longitudinal studies of relatively short duration. Methods: We combined 2 large longitudinal studies (the Danish Lung Cancer Screening Trial [DLCST] and the Evaluation of COPD Longitudinally to Identify Predictive Surrogate Endpoints [ECLIPSE]) of smokers or former smokers, with a wide range of AFL and CT lung density, and analysed data from 2148 participants who did not change smoking habits and who had at least 2 CT scans and 2 FEV₁ measurements at least 3 years apart. Results: Baseline correlation between FEV₁ and PD15 was high (r=0.716, 95% confidence interval [CI]: 0.694-0.736, p<0.001) indicating that at least half of the variation in FEV₁ can be explained by variation in CT lung density. Correlation between the decline in FEV₁ and progression of PD15 was considerably weaker (r= 0.081, 95% CI: 0.038-0.122, p<0.001). Conclusions: Correlation is very high between lung density and lung function in a broad spectrum of smokers and ex-smokers. In contrast, the temporal associations (slopes) are weakly correlated, probably due to uncertainty in the estimation of slopes within a time frame of 3-4 years.

Study on risk factors and phenotypes of acute exacerbations of chronic obstructive pulmonary disease in Guangzhou, China-design and baseline characteristics

BACKGROUND

To describe a study design that focuses on risk factors and patterns of chronic obstructive pulmonary disease (COPD) exacerbations.

METHODS

A 2-year, single centre, observational study was conducted in Guangzhou in China. The study enrolled 318 subjects with COPD aged 40-79 years, stratified into different but equally sized groups according to global initiative for chronic obstructive lung disease (GOLD) stage (including Stage 0) and 86 lung healthy controls. An assessment each year was scheduled including questionnaires, lung function testing, Chest X-ray and blood collection. A sub-group, called sub-group X, consisting of 203 subjects with COPD and 51 lung healthy controls, was selected to answer a symptom questionnaire daily (EXACT-PRO) via a BlackBerry Personal Digital Assistant (PDA) device. Upon an alert that indicated a change in daily symptom pattern, the patients were contacted by the clinic to decide whether they had experienced an exacerbation and should have an extra visit within 24-48 hours. At an extra visit, nasal and throat swabs, induced sputum and blood were collected. Air pollution, temperature and humidity were also monitored daily. A subset of sub-group X, called sub-group M that consisted of 52 COPD patients and 15 healthy controls was dedicated to measure muscle strength and a dexa scan.

RESULTS

More than 78% of the enrolled patients completed the study successfully. There appeared a difference between the patient groups and the controls in gender, age, body mass index (BMI), forced expiratory volume in 1 second (FEV1), FEV1/FVC and smoking at baseline. In sub-group X 90 out of 203 (44.4%) selected COPD patients developed one or more exacerbations in the 2-year observation period. They were more severe COPD patients according to GOLD stage at study start. On average most exacerbations occurred in the month March and the least number of exacerbations occurred in October.

CONCLUSIONS

This study with the obtained patient dataset will allow a better insight in many aspects of exacerbations in COPD (e.g., the identification, the risk factors, phenotypes and the biomarkers).

CT-Definable Subtypes of Chronic Obstructive Pulmonary Disease: A Statement of the Fleischner Society

The purpose of this statement is to describe and define the phenotypic abnormalities that can be identified on visual and quantitative evaluation of computed tomographic (CT) images in subjects with chronic obstructive pulmonary disease (COPD), with the goal of contributing to a personalized approach to the treatment of patients with COPD. Quantitative CT is useful for identifying and sequentially evaluating the extent of emphysematous lung destruction, changes in airway walls, and expiratory air trapping. However, visual assessment of CT scans remains important to describe patterns of altered lung structure in COPD. The classification system proposed and illustrated in this article provides a structured approach to visual and quantitative assessment of COPD. Emphysema is classified as centrilobular (subclassified as trace, mild, moderate, confluent, and advanced destructive emphysema), panlobular, and paraseptal (subclassified as mild or substantial). Additional important visual features include airway wall thickening, inflammatory small airways disease, tracheal abnormalities, interstitial lung abnormalities, pulmonary arterial enlargement, and bronchiectasis.

Do females behave differently in COPD exacerbation?

INTRODUCTION

Little is known about whether there is any sex effect on chronic obstructive lung disease (COPD) exacerbations. This study is intended to describe the possible sex-associated differences in exacerbation profile in COPD patients.

METHODS

A total of 384 COPD patients who were hospitalized due to exacerbation were evaluated retrospectively for their demographics and previous and current exacerbation characteristics.

RESULTS

The study was conducted on 109 (28%) female patients and 275 (72%) male patients. The mean age was 68.30±10.46 years. Although females had better forced expiratory volume in 1 second and near-normal forced vital capacity, they had much impaired arterial blood gas levels (partial oxygen pressure [PO2] was 36.28 mmHg vs 57.93 mmHg; partial carbon dioxide pressure [PCO2] was 45.97 mmHg vs 42.49 mmHg; P=0.001), indicating severe exacerbation with respiratory failure. More females had two exacerbations and two hospitalizations, while more men had one exacerbation and one hospitalization. Low adherence to treatment and pulmonary embolism were more frequent in females. Females had longer time from the onset of symptoms till the admission and longer hospitalization duration than males. Comorbidities were less in number and different in women (P<0.05). Women were undertreated and using more oral corticosteroids.

CONCLUSION

Current data showed that female COPD patients might be more prone to have severe exacerbations, a higher number of hospitalizations, and prolonged length of stay for hospitalization. They have a different comorbidity profile and might be undertreated for COPD.

Impact of chronic obstructive pulmonary disease (COPD) in the Asia-Pacific region: the EPIC Asia population-based survey

BACKGROUND

Chronic obstructive pulmonary disease (COPD) is a clinical syndrome encompassing a group of chronic, progressive, and debilitating respiratory conditions, that are characterized by incompletely reversible airflow limitation. Within the Asia-Pacific region, prevalence estimates have been derived using various protocols and study methods, and there is little data on the impact of COPD exacerbations. This study aimed to provide a comprehensive picture of the current prevalence and burden of COPD in this region.

METHODS

A population-based survey was conducted in nine Asia-Pacific territories between 01 February 2012 and 16 May 2012. Overall, 112,330 households were screened to identify eligible subjects (aged ≥40 years, with a physician diagnosis of COPD, chronic bronchitis or emphysema, or with identifiable symptoms of chronic bronchitis). Out of a sample of 69,279 individuals aged ≥40 years, 4,289 subjects with COPD were identified. Data were collected via face-to-face interviews or by fixed-line telephone, using a structured questionnaire. A total of 1,841 completed questionnaires were analyzed.

RESULTS

The overall estimated COPD prevalence was 6.2%, with 19.1% of subjects having severe COPD. In the 12 months prior to the survey, nearly half of all subjects (46%) had experienced exacerbations, and 19% had been hospitalized as a result of their condition. When subjects were asked about the impact of their condition on employment, 23% said their condition kept them from working, and 42% felt that their condition limited their ability to work or their activities. Of those who reported taking prescription drugs, 20% did not know the name of the drugs they were taking. Prescription of oral corticosteroids was common, with 44% of subjects having used these during the previous year to manage their respiratory symptoms; in contrast, inhaler use was low (25%). Only 37% of subjects had taken a lung function test, and the majority (89%) of those tested did not know their test results.

CONCLUSIONS

Across the Asia-Pacific territories surveyed, the prevalence of COPD is high, indicating a substantial socioeconomic burden. Our findings suggest that there is considerable room for improvement in the management of COPD, and highlight a need to enhance patient and physician education in the region.

IREB2 and GALC are associated with pulmonary artery enlargement in chronic obstructive pulmonary disease

Pulmonary hypertension is associated with advanced chronic obstructive pulmonary disease (COPD), although pulmonary vascular changes occur early in the course of the disease. Pulmonary artery (PA) enlargement (PAE) measured by computed tomography correlates with pulmonary hypertension and COPD exacerbation frequency. Genome-wide association studies of PAE in subjects with COPD have not been reported. To investigate whether genetic variants are associated with PAE within subjects with COPD, we investigated data from current and former smokers from the COPDGene Study and the Evaluation of COPD Longitudinally to Identify Predictive Surrogate Endpoints study. The ratio of the diameter of the PA to the diameter of the aorta (A) was measured using computed tomography. PAE was defined as PA/A greater than 1. A genome-wide association study for COPD with PAE was performed using subjects with COPD without PAE (PA/A ≤ 1) as a control group. A secondary analysis used smokers with normal spirometry as a control group. Genotyping was performed on Illumina platforms. The results were summarized using fixed-effect meta-analysis. Both meta-analyses revealed a genome-wide significant locus on chromosome 15q25.1 in IREB2 (COPD with versus without PAE, rs7181486; odds ratio [OR] = 1.32; P = 2.10 × 10(-8); versus smoking control subjects, rs2009746; OR = 1.42; P = 1.32 × 10(-9)). PAE was also associated with a region on 14q31.3 near the GALC gene (rs7140285; OR = 1.55; P = 3.75 × 10(-8)). Genetic variants near IREB2 and GALC likely contribute to genetic susceptibility to PAE associated with COPD. This study provides evidence for genetic heterogeneity associated with a clinically important COPD vascular subtype.

Lung cancer in patients with chronic obstructive pulmonary disease. Development and validation of the COPD Lung Cancer Screening Score

RATIONALE

Patients with chronic obstructive pulmonary disease (COPD) are at high risk for lung cancer (LC) and represent a potential target to improve the diagnostic yield of screening programs.

OBJECTIVES

To develop a predictive score for LC risk for patients with COPD.

METHODS

The Pamplona International Early Lung Cancer Detection Program (P-IELCAP) and the Pittsburgh Lung Screening Study (PLuSS) databases were analyzed. Only patients with COPD on spirometry were included. By logistic regression we determined which factors were independently associated with LC in PLuSS and developed a COPD LC screening score (COPD-LUCSS) to be validated in P-IELCAP.

MEASUREMENTS AND MAIN RESULTS

By regression analysis, age greater than 60, body mass index less than 25 kg/m(2), pack-years history greater than 60, and emphysema presence were independently associated with LC diagnosis and integrated into the COPD-LUCSS, which ranges from 0 to 10 points. Two COPD-LUCSS risk categories were proposed: low risk (scores 0-6) and high risk (scores 7-10). In comparison with low-risk patients, in both cohorts LC risk increased 3.5-fold in the high-risk category.

CONCLUSIONS

The COPD-LUCSS is a good predictor of LC risk in patients with COPD participating in LC screening programs. Validation in two different populations adds strength to the findings.

Anti-inflammatory effects of salmeterol/fluticasone propionate 50/250 mcg combination therapy in Japanese patients with chronic obstructive pulmonary disease

PURPOSE

Using sputum neutrophils as the primary measure, and other inflammation biomarkers, this study evaluated the anti-inflammatory effects of the combination salmeterol 50 mcg and fluticasone propionate 250 mcg (SFC 250) in Japanese patients with chronic obstructive pulmonary disease (COPD).

PATIENTS AND METHODS

Patients were treated in a randomized, double-blind, parallel group, placebo-controlled trial with SFC 250 twice daily (n=26) or placebo (n=26) for 12 weeks. At the start and end of treatment, inflammation biomarkers (sputum and serum), lung function, and health status (COPD Assessment Test [CAT] questionnaire) were measured.

RESULTS

Although a numerical decrease in differential neutrophil count was observed from baseline, SFC 250 did not significantly reduce sputum neutrophils compared with placebo, nor were there significant changes from baseline in the other biomarkers (sputum or serum), lung function, or CAT, versus placebo. Squamous epithelial cell contamination in some sputum samples rendered them unacceptable for analysis, which reduced the sample size to n=19 (SFC 250) and n=10 (placebo). However, inclusion of contaminated samples did not affect the overall trend of the outcome. Ad hoc bootstrap statistical analysis showed a 27.9% (SFC 250) and 1.3% (placebo) decrease in sputum neutrophils. Sputum IL-8 decreased by 43.2% after SFC 250 but increased by 48.3% with placebo. Responder analyses showed 42% of patients had ≥20% decrease in neutrophils from baseline; and 47% of patients had a ≥200 pg/mL change in sputum IL-8 following SFC 250 versus 20% after placebo; both changes are considered clinically relevant.

CONCLUSION

This study provides additional information about inflammation in Japanese COPD patients and is the first to study the anti-inflammatory effects of SFC 250 in this context and population. In the primary analysis, SFC 250 did not produce significant changes from baseline in sputum neutrophil levels or other sputum or serum inflammatory markers compared with placebo. Secondary ad hoc statistical analysis showed that SFC 250 reduced the number of sputum neutrophils and IL-8 compared with placebo.

Chronic Obstructive Pulmonary Disease: Pulmonary Function and CT Lung Attenuation Do Not Show Linear Correlation

PURPOSE

To determine whether the relationship between pulmonary function and computed tomographic (CT) lung attenuation in chronic obstructive pulmonary disease (COPD), which is traditionally described with single univariate and multivariate statistical models, could be more accurately described with a multiple model estimation approach.

MATERIALS AND METHODS

The study was approved by the local ethics committee. All participants provided written informed consent. The prediction of the percentage area with CT attenuation values less than -950 HU at inspiration (%LAA-950insp) and less than -910 HU at expiration (%LAA-910exp) obtained with single univariate and multivariate models was compared with that obtained with a multiple model estimation approach in 132 patients with COPD.

RESULTS

At univariate analysis, %LAA-950insp and %LAA-910exp values higher than the mean value of this cohort (19.1% and 22.0%) showed better correlation with percentage of predicted diffusing capacity of lung for carbon monoxide (Dlco%) than with airflow obstruction (forced expiratory volume in 1 second [FEV1]/vital capacity [VC]). Conversely, %LAA-950insp and %LAA-910exp values lower than the mean value were correlated with FEV1/VC but not with Dlco%. Multiple model estimation performed with two multivariate regressions, each selecting the most appropriate functional variables (FEV1/VC for mild parenchymal destruction, Dlco% and functional residual capacity for severe parenchymal destruction), predicted better than single multivariate regression both %LAA-950insp (R(2) = 0.75 vs 0.46) and %LAA-910exp (R(2) = 0.83 vs 0.63).

CONCLUSION

The relationship between pulmonary function data and CT densitometric changes in COPD varies with the level of lung attenuation impairment. The nonlinear profile of this relationship is accurately predicted with a multiple model estimation approach.

Secondhand Tobacco Smoke and COPD Risk in Smokers: A COPDGene Study Cohort Subgroup Analysis

BACKGROUND

Exposure to secondhand tobacco smoke (SHS) can be a risk factor for chronic obstructive pulmonary disease (COPD), but its role among relatively heavy smokers with potential co-exposure to workplace vapors, gas, dust, and fumes (VGDF) has not been studied.

METHODS

To estimate the contribution of SHS exposure to COPD risk, taking into account smoking effects and work-related exposures to VGDF, we quantified SHS based on survey responses for 1400 ever-employed subjects enrolled in the COPDGene study, all current or former smokers with or without COPD. Occupational exposures to VGDF were quantified based on a job exposure matrix. The associations between SHS and COPD were tested in multivariate logistic regression analyses adjusted for age, sex, VGDF exposure, and cumulative smoking.

RESULTS AND DISCUSSION

Exposures to SHS at work and at home during adulthood were associated with increased COPD risk: odds ratio (OR) = 1.12 (95% confidence interval [CI]: 1.02-1.23; p = 0.01) and OR = 1.09 (95%CI: 1.00-1.18; p = 0.04) per 10 years of exposure adjusted for smoking and other covariates, respectively. In addition, subjects with employment histories likely to entail exposure to VGDF were more likely to have COPD: OR = 1.52 (95%CI: 1.16-1.98; p < 0.01) (adjusted for other covariates). While adult home SHS COPD risk was attenuated among the heaviest smokers within the cohort, workplace SHS and job VGDF risks persisted in that stratum.

CONCLUSION

Among smokers all with at least 10 pack-years, adult home and work SHS exposures and occupational VGDF exposure are all associated with COPD.

Large trials, new knowledge: the changing face of COPD management

Large, well-designed, drug-treatment trials have allowed useful advances to be made in the treatment and diagnosis of chronic obstructive pulmonary disease (COPD). The two main clinical trial designs that provide evidence of effectiveness are randomised controlled trials (RCTs) and observational studies. RCTs are generally considered to provide more robust evidence than that obtained from observational studies and can generate informative secondary analyses in addition to the primary research query. In COPD, however, well-designed comparator-controlled RCTs, although successful, have been shown to have some limitations, such as a lack of generalisability. The findings of observational studies, whilst prone to bias, can generate valuable data and have also provided useful information relating to the efficacy of treatments in the current COPD management guidelines. This review focuses on major COPD studies published since 2007 (including UPLIFT, TIOSPIR, ECLIPSE and COPDGene), and assesses the influence such RCTs and large observational studies have had on our knowledge of COPD, and how these may impact future trial designs.

One-year change in health status and subsequent outcomes in COPD

BACKGROUND

Poor health status has been associated with morbidity and mortality in patients with COPD. To date, the impact of changes in health status on these outcomes remains unknown.

AIMS

To explore the relationship of clinically relevant changes in health status with exacerbation, hospitalisation or death in patients with COPD.

METHODS

Characteristics and health status (St George's Respiratory Questionnaire, SGRQ) were assessed over a period of 3 years in 2138 patients with COPD enrolled in the Evaluation of COPD Longitudinally to Identify Predictive Surrogate Endpoints (ECLIPSE) study: a longitudinal, prospective, observational study. Associations between change in health status (=4 units in SGRQ score) during year 1 and time to first exacerbation, hospitalisation and death during 2-year follow-up were assessed using Kaplan-Meier plots and log-rank test.

RESULTS

1832 (85.7%) patients (age 63.4±7.0 years, 65.4% male, FEV1 48.7±15.6% predicted) underwent assessment at baseline and 1 year. Compared with those who deteriorated, patients with improved or stable health status in year 1 have a lower likelihood of exacerbation (HR 0.78 (95% CI 0.67 to 0.89), p<0.001 and 0.84 (0.73 to 0.97), p=0.016, respectively), hospitalisation (0.72 (0.58 to 0.90), p=0.004 and 0.77 (0.62 to 0.96), p=0.023, respectively) or dying (0.61 (0.39 to 0.95), p=0.027 and 0.58 (0.37 to 0.92), p=0.019, respectively) during 2-year follow-up. This effect persisted after stratification for age and the number of exacerbations and hospitalisations during the first year of the study.

CONCLUSIONS

Patients with stable or improved health status during year 1 of ECLIPSE had a lower likelihood of exacerbation, hospitalisation or dying during 2-year follow-up. Interventions that stabilise and improve health status may also improve outcomes in patients with COPD.

TRIAL REGISTRATION NUMBER

NCT00292552, registered at ClinicalTrials.gov.

Free-breathing pulmonary 1H and Hyperpolarized 3He MRI: comparison in COPD and bronchiectasis

RATIONALE AND OBJECTIVES

In this proof-of-concept demonstration, we aimed to quantitatively and qualitatively compare pulmonary ventilation abnormalities derived from Fourier decomposition of free-breathing (1)H magnetic resonance imaging (FDMRI) to hyperpolarized (3)He MRI in subjects with chronic obstructive pulmonary disease (COPD) and bronchiectasis.

MATERIALS AND METHODS

All subjects provided written informed consent to a protocol approved by a local research ethics board and Health, Canada, and they underwent MRI, computed tomography (CT), spirometry, and plethysmography during a single 2-hour visit. Semiautomated segmentation was used to generate ventilation defect measurements derived from FDMRI and (3)He MRI, and these were compared using analysis of variance and Pearson correlations.

RESULTS

Twenty-six subjects were evaluated including 12 COPD subjects (67 ± 9 years) and 14 bronchiectasis subjects (70 ± 11 years). For COPD subjects, FDMRI and (3)He MRI ventilation defect percent (VDP) was 7 ± 6% and 24 ± 14%, respectively (P < .001; bias = -16 ± 9%). In COPD subjects, FDMRI was significantly correlated with (3)He MRI VDP (r = .88; P = .0001), (3)He MRI apparent diffusion coefficient (r = .71; P < .05), airways resistance (r = .60; P < .05), and RA950 (r = .80; P < .01). In subjects with bronchiectasis, FDMRI VDP (5 ± 3%) and (3)He MRI VDP (18 ± 9%) were significantly different (P < .001) and not correlated (P > .05). The Dice similarity coefficient (DSC) for FDMRI and (3)He MRI ventilation was 86 ± 7% for COPD and 86 ± 4% for bronchiectasis subjects (P > .05); the DSC for FDMRI ventilation defects and CT RA950 was 19 ± 20% in COPD and 2 ± 3% in bronchiectasis subjects (P < .01).

CONCLUSIONS

FDMRI and (3)He MRI VDP were strongly related in COPD but not in bronchiectasis subjects. In COPD only, FDMRI ventilation defects were spatially related with (3)He ventilation defects and emphysema.

Protocol for a human in vivo model of acute cigarette smoke inhalation challenge in smokers with COPD: monitoring the nasal and systemic immune response using a network biology approach

INTRODUCTION

Cigarette smoke contributes to a diverse range of diseases including chronic obstructive pulmonary disease (COPD), cardiovascular disorders and many cancers. There currently is a need for human challenge models, to assess the acute effects of a controlled cigarette smoke stimulus, followed by serial sampling of blood and respiratory tissue for advanced molecular profiling. We employ precision sampling of nasal mucosal lining fluid by absorption to permit soluble mediators measurement in eluates. Serial nasal curettage was used for transcriptomic analysis of mucosal tissue.

METHODS AND ANALYSIS

Three groups of strictly defined patients will be studied: 12 smokers with COPD (GOLD Stage 2) with emphysema, 12 matched smokers with normal lung function and no evidence of emphysema, and 12 matched never smokers with normal spirometry. Patients in the smoking groups are current smokers, and will be given full support to stop smoking immediately after this study. In giving a controlled cigarette smoke stimulus, all patients will have abstained from smoking for 12 h, and will smoke two cigarettes with expiration through the nose in a ventilated chamber. Before and after inhalation of cigarette smoke, a series of samples will be taken from the blood, nasal mucosal lining fluid and nasal tissue by curettage. Analysis of plasma nicotine and metabolites in relation to levels of soluble inflammatory mediators in nasal lining fluid and blood, as well as assessing nasal transcriptomics, ex vivo blood platelet aggregation and leucocyte responses to toll-like receptor agonists will be undertaken.

IMPLICATIONS

Development of acute cigarette smoke challenge models has promise for the study of molecular effects of smoking in a range of pathological processes.

ETHICS AND DISSEMINATION

This study was approved by the West London National Research Ethics Committee (12/LO/1101). The study findings will be presented at conferences and will be reported in peer-reviewed journals.

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.

The Prospective Non-Interventional DACCORD Study in the National COPD Registry in Germany: design and methods

Background

A variety of large randomized controlled trials (RCT’s) evaluating pharmacotherapy in chronic obstructive pulmonary disease (COPD) patients does exist. One of the drugs that has been tested is the new long-acting anticholinergic glycopyrronium bromide.

Methods

As the generalizability of results from RCT’s is questionable we designed a longitudinal, prospective non-interventional study (DACCORD) of two years duration plus two years extension with at least 6000 participants in approximately 500 primary and secondary care practices in Germany (within the new established COPD National Prospective Registry), to assess patient reported outcomes (PRO’s), lung function, adherence and drug safety. To circumvent the hurdle of inappropriate COPD diagnosis in a non-interventional trial, patients have to fulfill the inclusion criteria of the COPD disease management program (DMP) of the German statutory health insurances. Patient management should follow the German national COPD guidelines, which are based on Global Initiative for Chronic Obstructive Lung Disease 2007 (GOLD) report. Labels of prescribed drugs should also be taken into account. Patients received treatment as part of their standard care: at the discretion of the investigator patients were included in one of two arms. A: standard care with glycopyrronium containing regimen, and arm B: standard care without glycopyrronium.

Discussion

For 2016 we expect important results regarding longitudinal development of PRO’s including exacerbations, lung function, adherence and side effects. We also investigate applicability of the new GOLD staging system in usual care. Data on diagnostic and treatment modalities in current German primary and secondary care, as well as pharmaco-economic data will be generated.

Trial registration

1. German Register for non-interventional studies: http://www.vfa.de/de/arzneimittel-forschung/datenbanken-zu-arzneimitteln/nisdb.

2. EMA EnCePP http://www.encepp.eu/.

Common genetic variants associated with resting oxygenation in chronic obstructive pulmonary disease

Hypoxemia is a major complication of chronic obstructive pulmonary disease (COPD) that correlates with disease prognosis. Identifying genetic variants associated with oxygenation may provide clues for deciphering the heterogeneity in prognosis among patients with COPD. However, previous genetic studies have been restricted to investigating COPD candidate genes for association with hypoxemia. To report results from the first genome-wide association study (GWAS) of resting oxygen saturation (as measured by pulse oximetry [Spo2]) in subjects with COPD, we performed a GWAS of Spo2 in two large, well characterized COPD populations: COPDGene, including both the non-Hispanic white (NHW) and African American (AA) groups, and Evaluation of COPD Longitudinally to Identify Predictive Surrogate Endpoints (ECLIPSE). We identified several suggestive loci (P < 1 × 10(-5)) associated with Spo2 in COPDGene in the NHW (n = 2810) and ECLIPSE (n = 1758) groups, and two loci on chromosomes 14 and 15 in the AA group (n = 820) from COPDGene achieving a level of genome-wide significance (P < 5 × 10(-8)). The chromosome 14 single-nucleotide polymorphism, rs6576132, located in an intergenic region, was nominally replicated (P < 0.05) in the NHW group from COPDGene. The chromosome 15 single-nucleotide polymorphisms were rare in subjects of European ancestry, so the results could not be replicated. The chromosome 15 region contains several genes, including TICRR and KIF7, and is proximal to RHCG (Rh family C glyocoprotein gene). We have identified two loci associated with resting oxygen saturation in AA subjects with COPD, and several suggestive regions in subjects of European descent with COPD. Our study highlights the importance of investigating the genetics of complex traits in different racial groups.

Dissecting the genetics of chronic mucus hypersecretion in smokers with and without COPD

Smoking is a notorious risk factor for chronic mucus hypersecretion (CMH). CMH frequently occurs in chronic obstructive pulmonary disease (COPD). The question arises whether the same single-nucleotide polymorphisms (SNPs) are related to CMH in smokers with and without COPD. We performed two genome-wide association studies of CMH under an additive genetic model in male heavy smokers (≥20 pack-years) with COPD (n=849, 39.9% CMH) and without COPD (n=1348, 25.4% CMH), followed by replication and meta-analysis in comparable populations, and assessment of the functional relevance of significantly associated SNPs. Genome-wide association analysis of CMH in COPD and non-COPD subjects yielded no genome-wide significance after replication. In COPD, our top SNP (rs10461985, p=5.43×10(-5)) was located in the GDNF-AS1 gene that is functionally associated with the GDNF gene. Expression of GDNF in bronchial biopsies of COPD patients was significantly associated with CMH (p=0.007). In non-COPD subjects, four SNPs had a p-value <10(-5) in the meta-analysis, including a SNP (rs4863687) in the MAML3 gene, the T-allele showing modest association with CMH (p=7.57×10(-6), OR 1.48) and with significantly increased MAML3 expression in lung tissue (p=2.59×10(-12)). Our data suggest the potential for differential genetic backgrounds of CMH in individuals with and without COPD.

Chronic Obstructive Pulmonary Disease heterogeneity: challenges for health risk assessment, stratification and management

Background and hypothesis

Heterogeneity in clinical manifestations and disease progression in Chronic Obstructive Pulmonary Disease (COPD) lead to consequences for patient health risk assessment, stratification and management. Implicit with the classical "spill over" hypothesis is that COPD heterogeneity is driven by the pulmonary events of the disease. Alternatively, we hypothesized that COPD heterogeneities result from the interplay of mechanisms governing three conceptually different phenomena: 1) pulmonary disease, 2) systemic effects of COPD and 3) co-morbidity clustering, each of them with their own dynamics.

Objective and method

To explore the potential of a systems analysis of COPD heterogeneity focused on skeletal muscle dysfunction and on co-morbidity clustering aiming at generating predictive modeling with impact on patient management. To this end, strategies combining deterministic modeling and network medicine analyses of the Biobridge dataset were used to investigate the mechanisms of skeletal muscle dysfunction. An independent data driven analysis of co-morbidity clustering examining associated genes and pathways was performed using a large dataset (ICD9-CM data from Medicare, 13 million people). Finally, a targeted network analysis using the outcomes of the two approaches (skeletal muscle dysfunction and co-morbidity clustering) explored shared pathways between these phenomena.

Results

(1) Evidence of abnormal regulation of skeletal muscle bioenergetics and skeletal muscle remodeling showing a significant association with nitroso-redox disequilibrium was observed in COPD; (2) COPD patients presented higher risk for co-morbidity clustering than non-COPD patients increasing with ageing; and, (3) the on-going targeted network analyses suggests shared pathways between skeletal muscle dysfunction and co-morbidity clustering.

Conclusions

The results indicate the high potential of a systems approach to address COPD heterogeneity. Significant knowledge gaps were identified that are relevant to shape strategies aiming at fostering 4P Medicine for patients with COPD.

The metabolomics of airway diseases, including COPD, asthma and cystic fibrosis

Chronic obstructive pulmonary disease (COPD), asthma and cystic fibrosis (CF) are characterized by airway obstruction and an inflammatory process. Reaching early diagnosis and discrimination of subtypes of these respiratory diseases are quite a challenging task than other chronic illnesses. Metabolomics is the study of metabolic pathways and the measurement of unique biochemical molecules generated in a living system. In the last decade, metabolomics has already proved to be useful for the characterization of several pathological conditions and offers promises as a clinical tool. In this article, we review the current state of the metabolomics of COPD, asthma and CF with a focus on the different methods and instrumentation being used for the discovery of biomarkers in research and translation into clinic as diagnostic aids for the choice of patient-specific therapies.

Variability of within-breath reactance in COPD patients and its association with dyspnoea

The forced oscillation technique can identify expiratory flow limitation (EFL) when a large difference in inspiratory and expiratory reactance (ΔXrs) occurs. However, flow limitation can vary from breath to breath, and so we compared a multiple-breath ΔXrs approach to the traditional breath-by-breath assessment of EFL. We investigated the within- and between-day reproducibility and the factors that affect the size of ΔXrs when used as a continuous measurement over multiple breaths. In addition, we examined how multiple-breath ΔXrs relates to the sensation of breathlessness.

425 moderate to very severe chronic obstructive pulmonary disease (COPD) patients and 229 controls were included. Spirometry and impedance measurements were performed on a MasterScope CT Impulse Oscillation System.

Median ΔXrs approached zero in healthy controls with little variation between measurements. COPD patients generally had higher ΔXrs and higher variability. The COPD patients with ΔXrs >0.1 kPa·L−1·s−1 were prone to be more breathless and had a higher modified Medical Research Council dyspnoea scale score. In controls, the 95th percentile of ΔXrs was as low as 0.07 kPa·L−1·s−1.

We describe a new method to assess EFL at a patient level and propose a cut-off, mean ΔXrs >0.1 kPa·L−1·s−1, as a way to identify COPD patients who are more likely to report dyspnoea.

Non-emphysematous chronic obstructive pulmonary disease is associated with diabetes mellitus

BACKGROUND

Chronic obstructive pulmonary disease (COPD) has been classically divided into blue bloaters and pink puffers. The utility of these clinical subtypes is unclear. However, the broader distinction between airway-predominant and emphysema-predominant COPD may be clinically relevant. The objective was to define clinical features of emphysema-predominant and non-emphysematous COPD patients.

METHODS

Current and former smokers from the Genetic Epidemiology of COPD Study (COPDGene) had chest computed tomography (CT) scans with quantitative image analysis. Emphysema-predominant COPD was defined by low attenuation area at -950 Hounsfield Units (LAA-950) ≥10%. Non-emphysematous COPD was defined by airflow obstruction with minimal to no emphysema (LAA-950 < 5%).

RESULTS

Out of 4197 COPD subjects, 1687 were classified as emphysema-predominant and 1817 as non-emphysematous; 693 had LAA-950 between 5-10% and were not categorized. Subjects with emphysema-predominant COPD were older (65.6 vs 60.6 years, p < 0.0001) with more severe COPD based on airflow obstruction (FEV1 44.5 vs 68.4%, p < 0.0001), greater exercise limitation (6-minute walk distance 1138 vs 1331 ft, p < 0.0001) and reduced quality of life (St. George's Respiratory Questionnaire score 43 vs 31, p < 0.0001). Self-reported diabetes was more frequent in non-emphysematous COPD (OR 2.13, p < 0.001), which was also confirmed using a strict definition of diabetes based on medication use. The association between diabetes and non-emphysematous COPD was replicated in the ECLIPSE study.

CONCLUSIONS

Non-emphysematous COPD, defined by airflow obstruction with a paucity of emphysema on chest CT scan, is associated with an increased risk of diabetes. COPD patients without emphysema may warrant closer monitoring for diabetes, hypertension, and hyperlipidemia and vice versa.

TRIAL REGISTRATION

Clinicaltrials.gov identifiers: COPDGene NCT00608764, ECLIPSE NCT00292552.

Chest CT measures of muscle and adipose tissue in COPD: gender-based differences in content and in relationships with blood biomarkers

RATIONALE AND OBJECTIVES

Computed tomography (CT) of the chest can be used to assess pectoralis muscle area (PMA) and subcutaneous adipose tissue (SAT) area. Adipose tissue content is associated with inflammatory mediators in chronic obstructive pulmonary disease (COPD) subjects. Based on gender differences in body composition, we aimed to assess the hypothesis that in subjects with COPD, the relationships between PMA, SAT, and blood biomarkers of inflammation differ by gender.

MATERIALS AND METHODS

We compared chest CT measures of PMA and SAT on a single slice at aortic arch and supraesternal notch levels from 73 subjects (28 women) with COPD between genders. The relationships of PMA and SAT area to biomarkers were assessed using within-gender regression models.

RESULTS

Women had a lesser PMA and a greater SAT area than men (difference range for PMA, 13.3-22.8 cm²; for SAT, 11.8-12.4 cm²; P < .05 for all comparisons) at both anatomic levels. These differences in PMA and SAT remained significant after adjustment for age and body mass index. Within-gender regression models adjusted for age showed that SAT was directly associated with C-reactive protein (for aortic arch level, P = .04) and fibrinogen (for both anatomic locations, P = .003) only in women, whereas PMA was not associated with any biomarkers in either gender.

CONCLUSIONS

It appears that in subjects with COPD, there are gender-based differences in the relationships between subcutaneous adipose tissue and inflammatory biomarkers.