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

Gender modifies the effect of body mass index on lung function decline in mild-to-moderate COPD patients: a pooled analysis

Background

Low body weight is associated with poor prognosis in patients with chronic obstructive pulmonary disease (COPD). However, it is not known whether gender modifies this relationship.

Methods

We pooled data of 8686 COPD patients from 7 studies with a median length of 36-months of follow up. Using a longitudinal natural cubic spline regression model, we examined the dose–response relationship between body mass index (BMI) and the rate of decline in forced expiratory volume in one second (FEV₁) in patients with GOLD 1 and 2 disease, stratified by gender and adjusted for age, smoking status, and cohort effects.

Results

There was an inverse linear relationship between BMI and the rate of FEV₁ decline in GOLD Grades 1 and 2, which was modified by gender (p < 0.001). In male patients, an increase of BMI by 1 kg/m² reduced FEV₁ decline by 1.05 mL/year (95% CI 0.96, 1.14). However, in female patients, BMI status did not have a clinically meaningful impact on FEV₁ decline: an increase of baseline BMI by 1 kg/m² reduced FEV₁ decline by 0.16 ml/year (95% CI 0.11, 0.21). These gender-modified relationships were similar between GOLD 1 and 2 patients, and between current and former smokers.

Conclusion

In mild to moderate COPD, higher BMI was associated with a less rapid decline of FEV₁ in male patients whereas this association was minimal in females patients. This gender-specific BMI effect was independent of COPD severity and smoking status.

Relationship between Emphysema Progression at CT and Mortality in Ever-Smokers: Results from the COPDGene and ECLIPSE Cohorts

Background The relationship between emphysema progression and long-term outcomes is unclear. Purpose To determine the relationship between emphysema progression at CT and mortality among participants with emphysema. Materials and Methods In a secondary analysis of two prospective observational studies, COPDGene (clinicaltrials.gov, NCT00608764) and Evaluation of Chronic Obstructive Pulmonary Disease Longitudinally to Identify Predictive Surrogate End-points (ECLIPSE; clinicaltrials.gov, NCT00292552), emphysema was measured at CT at two points by using the volume-adjusted lung density at the 15th percentile of the lung density histogram (hereafter, lung density perc15) method. The association between emphysema progression rate and all-cause mortality was analyzed by using Cox regression adjusted for ethnicity, sex, baseline age, pack-years, and lung density, baseline and change in smoking status, forced expiratory volume in 1 second, and 6-minute walk distance. In COPDGene, respiratory mortality was analyzed by using the Fine and Gray method. Results A total of 5143 participants (2613 men [51%]; mean age, 60 years ± 9 [standard deviation]) in COPDGene and 1549 participants (973 men [63%]; mean age, 62 years ± 8) in ECLIPSE were evaluated, of which 2097 (40.8%) and 1179 (76.1%) had emphysema, respectively. Baseline imaging was performed between January 2008 and December 2010 for COPDGene and January 2006 and August 2007 for ECLIPSE. Follow-up imaging was performed after 5.5 years ± 0.6 in COPDGene and 3.0 years ± 0.2 in ECLIPSE, and mortality was assessed over the ensuing 5 years in both. For every 1 g/L per year faster rate of decline in lung density perc15, all-cause mortality increased by 8% in COPDGene (hazard ratio [HR], 1.08; 95% CI: 1.01, 1.16; P = .03) and 6% in ECLIPSE (HR, 1.06; 95% CI: 1.00, 1.13; P = .045). In COPDGene, respiratory mortality increased by 22% (HR, 1.22; 95% CI: 1.13, 1.31; P < .001) for the same increase in the rate of change in lung density perc15. Conclusion In ever-smokers with emphysema, emphysema progression at CT was associated with increased all-cause and respiratory mortality. © RSNA, 2021 Online supplemental material is available for this article. See also the editorial by Lee and Park in this issue.

Respiratory exacerbations are associated with muscle loss in current and former smokers

OBJECTIVES

Muscle wasting is a recognised extra-pulmonary complication in chronic obstructive pulmonary disease and has been associated with increased risk of death. Acute respiratory exacerbations are associated with reduction of muscle function, but there is a paucity of data on their long-term effect. This study explores the relationship between acute respiratory exacerbations and long-term muscle loss using serial measurements of CT derived pectoralis muscle area (PMA).

DESIGN AND SETTING

Participants were included from two prospective, longitudinal, observational, multicentre cohorts of ever-smokers with at least 10 pack-year history.

PARTICIPANTS

The primary analysis included 1332 (of 2501) participants from Evaluation of COPD Longitudinally to Identify Predictive Surrogate Endpoints (ECLIPSE) and 4384 (of 10 198) participants from Genetic Epidemiology of COPD (COPDGene) who had complete data from their baseline and follow-up visits.

INTERVENTIONS

PMA was measured on chest CT scans at two timepoints. Self-reported exacerbation data were collected from participants in both studies through the use of periodic longitudinal surveys.

MAIN OUTCOME MEASURES

Age-related and excess muscle loss over time.

RESULTS

Age, sex, race and body mass index were associated with baseline PMA. Participants experienced age-related decline at the upper end of reported normal ranges. In ECLIPSE, the exacerbation rate over time was associated with an excess muscle area loss of 1.3% (95% CI 0.6 to 1.9, p<0.001) over 3 years and in COPDGene with an excess muscle area loss of 2.1% (95% CI 1.2 to 2.8, p<0.001) over 5 years. Excess muscle area decline was absent in 273 individuals who participated in pulmonary rehabilitation.

CONCLUSIONS

Exacerbations are associated with accelerated skeletal muscle loss. Each annual exacerbation was associated with the equivalent of 6 months of age-expected decline in muscle mass. Ameliorating exacerbation-associated muscle loss represents an important therapeutic target.

Predicting Re-Exacerbation Timing and Understanding Prolonged Exacerbations: An Analysis of Patients with COPD in the ECLIPSE Cohort

PURPOSE

Understanding risk factors for an acute exacerbation of chronic obstructive pulmonary disease (AECOPD) is important for optimizing patient care. We re-analyzed data from the Evaluation of COPD Longitudinally to Identify Predictive Surrogate Endpoints (ECLIPSE) study (NCT00292552) to identify factors predictive of re-exacerbations and associated with prolonged AECOPDs.

METHODS

Patients with COPD from ECLIPSE with moderate/severe AECOPDs were included. The end of the first exacerbation was the index date. Timing of re-exacerbation risk was assessed in patients with 180 days' post-index-date follow-up data. Factors predictive of early (1-90 days) vs late (91-180 days) vs no re-exacerbation were identified using a multivariable partial-proportional-odds-predictive model. Explanatory logistic-regression modeling identified factors associated with prolonged AECOPDs.

RESULTS

Of the 1,554 eligible patients from ECLIPSE, 1,420 had 180 days' follow-up data: more patients experienced early (30.9%) than late (18.7%) re-exacerbations; 50.4% had no re-exacerbation within 180 days. Lower post-bronchodilator FEV1 (P=0.0019), a higher number of moderate/severe exacerbations on/before index date (P<0.0001), higher St. George's Respiratory Questionnaire total score (P=0.0036), and season of index exacerbation (autumn vs winter, P=0.00164) were identified as predictors of early (vs late/none) re-exacerbation risk within 180 days. Similarly, these were all predictors of any (vs none) re-exacerbation risk within 180 days. Median moderate/severe AECOPD duration was 12 days; 22.7% of patients experienced a prolonged AECOPD. The odds of experiencing a prolonged AECOPD were greater for severe vs moderate AECOPDs (adjusted odds ratio=1.917, P=0.002) and lower for spring vs winter AECOPDs (adjusted odds ratio=0.578, P=0.017).

CONCLUSION

Prior exacerbation history, reduced lung function, poorer respiratory-related quality-of-life (greater disease burden), and season may help identify patients who will re-exacerbate within 90 days of an AECOPD. Severe AECOPDs and winter AECOPDs are likely to be prolonged and may require close monitoring.

Using Blood Eosinophil Count as a Biomarker to Guide Corticosteroid Treatment for Chronic Obstructive Pulmonary Disease

Treating patients hospitalised with acute exacerbations of chronic obstructive pulmonary disease (COPD) usually involves administering systemic corticosteroids. The many unwanted side effects associated with this treatment have led to increased interest in minimising the accumulated corticosteroid dose necessary to treat exacerbations. Studies have shown that short-term treatment with corticosteroids is preferred, and recent trials have shown that biomarkers can be used to further reduce exposure to corticosteroids. Interestingly, high eosinophil counts in patients with acute exacerbations of COPD are indicative of an eosinophilic phenotype with a distinct response to treatment with corticosteroids. In addition, post-hoc analysis of randomised control trials have shown that higher blood eosinophil counts at the start of the study predict a greater response to inhaled corticosteroids in stable COPD. In this review, we examine the studies on this topic, describe how blood eosinophil cell count may be used as a biomarker to guide treatment with corticosteroids, and identify some relevant challenges.

Should the number of acute exacerbations in the previous year be used to guide treatments in COPD?

BACKGROUND

In contemporary management of chronic obstructive pulmonary disease (COPD), the frequent exacerbator phenotype, based on a 12-month history of acute exacerbation of COPD (AECOPD), is a major determinant of therapeutic recommendations. However, there is considerable debate as to the stability of this phenotype over time.

METHODS

We used fundamental principles in time-to-event analysis to demonstrate that variation in the frequent exacerbator phenotype has two major sources: variability in the underlying AECOPD rate and randomness in the occurrence of individual AECOPDs. We re-analysed data from two large cohorts, the Evaluation of COPD Longitudinally to Identify Predictive Surrogate Endpoints (ECLIPSE) study and the SubPopulations and InteRmediate OutcoMes In COPD Study (SPIROMICS), using a Bayesian model that separated these sources of variability. We then evaluated the stability of the frequent exacerbator phenotype based on these results.

RESULTS

In both cohorts, the pattern of AECOPDs strongly supported the presence of an individual-specific underlying AECOPD rate which is stable over time (Bayes Factor less than 0.001). Despite this, the observed AECOPD rate can vary markedly year-to-year within individual patients. For those with an underlying rate of 0.8-3.1 events·year-1, the frequent exacerbator classification, based on the observed rate, changes more than 30% of the time over two consecutive years due to chance alone. This value increases to more than 45% for those with an underlying rate of 1.2-2.2 events·year-1.

CONCLUSIONS

While the underlying AECOPD rate is a stable trait, the frequent exacerbator phenotype based on observed AECOPD patterns is unstable, so much so that its suitability for informing treatment decisions should be questioned. Whether evaluating AECOPD history over longer durations or using multivariate prediction models can result in more stable phenotyping needs to be evaluated.

Evaluation of lung densitometric and volumetric changes in silicosis patients using three-dimensional software for multidetector CT and the relationship with profusion scores

AIM

To evaluate the density and volume changes in the lungs of silicosis patients and their relationship with the disease severity classification of the International Labor Organization (ILO).

MATERIALS AND METHODS

The multidetector computed tomography (CT) images of 44 patients diagnosed with silicosis and 32 controls that underwent thoracic CT due to trauma were evaluated. Patients with silicosis were divided into three categories according to the ILO classification. Data related to the total lung volume, total lung mean density, lung opacity score, percentage of lung high opacity, and mean density in the lower and upper lobes were obtained using three-dimensional (3D) software.

RESULTS

There was no significant difference between the total lung mean densities of the silicosis and control groups (p=0.213); however, a significant difference was observed between the two groups in terms of the total lung volume (p<0.0001). According to the ILO classification, there was a significant difference between the disease severity categories in relation to the percentage of lung high opacity (p=0.000005). A strong correlation was detected between disease severity and high opacity percentage (p<0.0001, r=0.804). According to the ILO classification, there was also a significant difference between disease severity categories in terms of the lung opacity score (p=0.000144), as well as a moderate correlation between disease severity and opacity score (p<0.0001, r=0.580).

CONCLUSION

Total lung volume is a CT finding that shows variation in exposure to crystalline silica. The percentage of high opacity determined using multidetector CT is an effective parameter in evaluating disease severity.

CT Imaging and Comorbidities in COPD: Beyond Lung Cancer Screening

Comorbidities significantly contribute to morbidity, mortality, and health-care costs in individuals with COPD. Comorbidity prevalence does not always correlate with lung disease severity, and the elevated risk of certain comorbidities is often independent of shared risk factors such as tobacco burden. Although COPD management guidelines recognize the importance of identifying and treating comorbidities as part of the comprehensive management of COPD patients, little guidance is provided regarding best screening practices. Whereas universal comorbidity screening in COPD patients is likely not cost-effective, targeted early screening and treatment in those at highest risk may have a significant impact on COPD outcomes. Recent studies suggest that certain radiographic features on thoracic imaging may serve as surrogate markers of comorbidity in patients with COPD. This review evaluates these studies in the context of the growing availability of chest CT scans in the lung cancer screening era and discusses how chest CT imaging can be leveraged to identify those COPD patients at highest risk for comorbid disease.

Prognostic value of clinically important deterioration in COPD: IMPACT trial analysis

INTRODUCTION

Clinically important deterioration (CID) is a multicomponent measure for assessing disease worsening in chronic obstructive pulmonary disease (COPD). This analysis investigated the prognostic value of a CID event on future clinical outcomes and the effect of single-inhaler triple versus dual therapy on reducing CID risk in patients in the IMPACT trial.

METHODS

IMPACT was a phase III, double-blind, 52-week, multicentre trial. Patients with symptomatic COPD and at least one moderate/severe exacerbation in the prior year were randomised 2:2:1 to fluticasone furoate/umeclidinium/vilanterol (FF/UMEC/VI) 100/62.5/25 µg, FF/VI 100/25 µg or UMEC/VI 62.5/25 µg. CID at the time-point of interest was defined as a moderate/severe exacerbation, ≥100 mL decrease in trough forced expiratory volume in 1 s or deterioration in health status (increase of ≥4.0 units in St George's Respiratory Questionnaire total score or increase of ≥2.0 units in COPD Assessment Test score) from baseline. A treatment-independent post hoc prognostic analysis compared clinical outcomes up to week 52 in patients with/without a CID by week 28. A prospective analysis evaluated time to first CID with each treatment.

RESULTS

Patients with a CID by week 28 had significantly increased exacerbation rates after week 28, smaller improvements in lung function and health status at week 52 (all p<0.001), and increased risk of all-cause mortality after week 28 versus patients who were CID-free. FF/UMEC/VI significantly reduced CID risk versus dual therapies (all p<0.001).

CONCLUSIONS

Prevention of short-term disease worsening was associated with better long-term clinical outcomes. FF/UMEC/VI reduced CID risk versus dual therapies; this effect may improve long-term prognosis in this population.

The lower the eosinophils, the stronger the inflammatory response? The relationship of different levels of eosinophils with the degree of inflammation in acute exacerbation chronic obstructive pulmonary disease (AECOPD)

Background

Blood eosinophil levels are a known marker for the effects of therapy in patients with chronic obstructive pulmonary disease (COPD). This study aimed to clarify the cutoff values for blood eosinophils (EOS) to predict exacerbation risk and prognosis of acute exacerbation COPD (AECOPD) and investigate their correlation using inflammatory indicators and clinical characteristics.

Methods

In this observational study of 174 patients with AECOPD, we assessed the relationship between EOS and COPD. According to the percentage of blood EOS, patients were grouped into two groups (Group 1: EOS <2%, n=98; Group 2: EOS ≥2%, n=76), and Group 2 was further divided into Group A (2%≤ EOS <4%) and Group B (EOS ≥4%) based on a cutoff value of 4%. Patients received standardized treatment after collection of peripheral blood specimen. Associations of EOS with laboratory indicators before any treatment in hospital and with clinical data were compared.

Results

Patients in Group 1 showed significantly severe inflammation, worse pulmonary function, longer length of stay (LOS) (P<0.001), higher mMRC score (P<0.05), higher CAT score (P<0.05), higher rates of mortality (P<0.05), and greater noninvasive mechanical ventilation usage (P<0.05) compared with Group 2. Intriguingly, the CRP, total mMRC and CAT scores of patients in Group A were significantly lower than those in Group B (P<0.001; P<0.01; P<0.05, respectively). Pearson correlation analysis showed that a low percentage blood eosinophil level was negatively associated with higher WBC count (r=–0.155, P<0.05), NLR (r=–0.227, P<0.01) and CRP (r=–0.308, P<0.01).

Conclusions

Different cutoff values for percentage blood EOS might be useful biomarkers for predicting the severity of exacerbation and prognosis of inpatients with AECOPD.

Biomarkers: Opportunities and Challenges for Drug Development in the Current Regulatory Landscape

Biomarkers are widely used at every stage of drug discovery and development. Utilisation of biomarkers has a potential to make drug discovery, development and approval processes more efficient. An overview of the current global regulatory landscape is presented in this article with particular emphasis on the validation and qualification of biomarkers, as well as legal framework for companion diagnostics. Furthermore, this article shows how the number of approved drugs with at least 1 biomarker used during development (biomarker acceptance) is affected by the recent advances in the biomarker regulations. More than half of analysed approvals were supported by biomarker data and there has been a slight increase in acceptance of biomarkers in recent years, even though the growth is not continuous. For certain pharmacotherapeutic groups, approvals with biomarkers are more common than without. Examples include immunosuppressants, immunostimulants, drugs used in diabetes, antithrombotic drugs, antineoplastic agents and antivirals. As a conclusion, potential benefits, challenges and opportunities of using biomarkers in drug discovery and development in the current regulatory landscape are summarised and discussed.

Extracellular matrix remodelling in COPD

The extracellular matrix (ECM) of the lung plays several important roles in lung function, as it offers a low resistant pathway that allows the exchange of gases, provides compressive strength and elasticity that supports the fragile alveolar-capillary intersection, controls the binding of cells with growth factors and cell surface receptors and acts as a buffer against retention of water.COPD is a chronic inflammatory respiratory condition, characterised by various conditions that result in progressive airflow limitation. At any stage in the course of the disease, acute exacerbations of COPD may occur and lead to accelerated deterioration of pulmonary function. A key factor of COPD is airway remodelling, which refers to the serious alterations of the ECM affecting airway wall thickness, resistance and elasticity. Various studies have shown that serum biomarkers of ECM turnover are significantly associated with disease severity in patients with COPD and may serve as potential targets to control airway inflammation and remodelling in COPD. Unravelling the complete molecular composition of the ECM in the diseased lungs will help to identify novel biomarkers for disease progression and therapy.

Vitamin D Metabolism Is Dysregulated in Asthma and Chronic Obstructive Pulmonary Disease

Rationale: Vitamin D deficiency is common in patients with asthma and chronic obstructive pulmonary disease (COPD). Low 25-hydroxyvitamin D (25[OH]D) levels may represent a cause or a consequence of these conditions.Objectives: To determine whether vitamin D metabolism is altered in asthma or COPD.Methods: We conducted a longitudinal study in 186 adults to determine whether the 25(OH)D response to six oral doses of 3 mg vitamin D₃, administered over 1 year, differed between those with asthma or COPD versus control subjects. Serum concentrations of vitamin D₃, 25(OH)D₃, and 1α,25-dihydroxyvitamin D₃ (1α,25[OH]₂D₃) were determined presupplementation and postsupplementation in 93 adults with asthma, COPD, or neither condition, and metabolite-to-parent compound molar ratios were compared between groups to estimate hydroxylase activity. Additionally, we analyzed 14 datasets to compare expression of 1α,25(OH)₂D₃-inducible gene expression signatures in clinical samples taken from adults with asthma or COPD versus control subjects.Measurements and Main Results: The mean postsupplementation 25(OH)D increase in participants with asthma (20.9 nmol/L) and COPD (21.5 nmol/L) was lower than in control subjects (39.8 nmol/L; P = 0.001). Compared with control subjects, patients with asthma and COPD had lower molar ratios of 25(OH)D₃-to-vitamin D₃ and higher molar ratios of 1α,25(OH)₂D₃-to-25(OH)D₃ both presupplementation and postsupplementation (P ≤ 0.005). Intergroup differences in 1α,25(OH)₂D₃-inducible gene expression signatures were modest and variable if statistically significant.Conclusions: Attenuation of the 25(OH)D response to vitamin D supplementation in asthma and COPD associated with reduced molar ratios of 25(OH)D₃-to-vitamin D₃ and increased molar ratios of 1α,25(OH)₂D₃-to-25(OH)D₃ in serum, suggesting that vitamin D metabolism is dysregulated in these conditions.

Treatable traits qualifying for nonpharmacological interventions in COPD patients upon first referral to a pulmonologist: the COPD sTRAITosphere

Introduction

The present study assessed the prevalence of nine treatable traits (TTs) pinpointing nonpharmacological interventions in patients with COPD upon first referral to a pulmonologist, how these TTs co-occurred and whether and to what extent the TTs increased the odds having a severely impaired health status.

Methods

Data were collected from a sample of 402 COPD patients. A second sample of 381 patients with COPD was used for validation. Nine TTs were assessed: current smoking status, activity-related dyspnoea, frequent exacerbations <12 months, severe fatigue, depressed mood, poor physical capacity, low physical activity, poor nutritional status and a low level of self-management activation. For each TT the odds ratio (OR) of having a severe health status impairment was calculated. Furthermore, a graphic representation was created, the COPD sTRAITosphere, to visualise TTs prevalence and OR.

Results

On average 3.9±2.0 TTs per patient were observed. These TTs occurred relatively independently of each other and coexisted in 151 unique combinations. A significant positive correlation was found between the number of TTs and Clinical COPD Questionnaire total score (r=0.58; p<0.001). Patients with severe fatigue (OR: 8.8), severe activity-related dyspnoea (OR: 5.8) or depressed mood (OR: 4.2) had the highest likelihood of having a severely impaired health status. The validation sample corroborated these findings.

Conclusions

Upon first referral to a pulmonologist, COPD patients show multiple TTs indicating them to several nonpharmacological interventions. These TTs coexist in many different combinations, are relatively independent and increase the likelihood of having a severely impaired health status.

Relative contributions of family history and a polygenic risk score on COPD and related outcomes: COPDGene and ECLIPSE studies

INTRODUCTION

Family history is a risk factor for chronic obstructive pulmonary disease (COPD). We previously developed a COPD risk score from genome-wide genetic markers (Polygenic Risk Score, PRS). Whether the PRS and family history provide complementary or redundant information for predicting COPD and related outcomes is unknown.

METHODS

We assessed the predictive capacity of family history and PRS on COPD and COPD-related outcomes in non-Hispanic white (NHW) and African American (AA) subjects from COPDGene and ECLIPSE studies. We also performed interaction and mediation analyses.

RESULTS

In COPDGene, family history and PRS were significantly associated with COPD in a single model (PFamHx <0.0001; PPRS<0.0001). Similar trends were seen in ECLIPSE. The area under the receiver operator characteristic curve for a model containing family history and PRS was significantly higher than a model with PRS (p=0.00035) in NHWs and a model with family history (p<0.0001) alone in NHWs and AAs. Both family history and PRS were significantly associated with measures of quantitative emphysema and airway thickness. There was a weakly positive interaction between family history and the PRS under the additive, but not multiplicative scale in NHWs (relative excess risk due to interaction=0.48, p=0.04). Mediation analyses found that a significant proportion of the effect of family history on COPD was mediated through PRS in NHWs (16.5%, 95% CI 9.4% to 24.3%), but not AAs.

CONCLUSION

Family history and the PRS provide complementary information for predicting COPD and related outcomes. Future studies can address the impact of obtaining both measures in clinical practice.

Genome-Wide Gene-by-Smoking Interaction Study of Chronic Obstructive Pulmonary Disease

Risk of chronic obstructive pulmonary disease (COPD) is determined by both cigarette smoking and genetic susceptibility, but little is known about gene-by-smoking interactions. We performed a genome-wide association analysis of 179,689 controls and 21,077 COPD cases from UK Biobank subjects of European ancestry recruited from 2006 to 2010, considering genetic main effects and gene-by-smoking interaction effects simultaneously (2-degrees-of-freedom (df) test) as well as interaction effects alone (1-df interaction test). We sought to replicate significant results in COPDGene (United States, 2008-2010) and SpiroMeta Consortium (multiple countries, 1947-2015) data. We considered 2 smoking variables: 1) ever/never and 2) current/noncurrent. In the 1-df test, we identified 1 genome-wide significant locus on 15q25.1 (cholinergic receptor nicotinic β4 subunit, or CHRNB4) for ever- and current smoking and identified PI*Z allele (rs28929474) of serpin family A member 1 (SERPINA1) for ever-smoking and 3q26.2 (MDS1 and EVI1 complex locus, or MECOM) for current smoking in an analysis of previously reported COPD loci. In the 2-df test, most of the significant signals were also significant for genetic marginal effects, aside from 16q22.1 (sphingomyelin phosphodiesterase 3, or SMPD3) and 19q13.2 (Egl-9 family hypoxia inducible factor 2, or EGLN2). The significant effects at 15q25.1 and 19q13.2 loci, both previously described in prior genome-wide association studies of COPD or smoking, were replicated in COPDGene and SpiroMeta. We identified interaction effects at previously reported COPD loci; however, we failed to identify novel susceptibility loci.

Advances in Chronic Obstructive Pulmonary Disease Imaging

Chest computed tomography (CT) imaging is a useful tool that provides in vivo information regarding lung structure. Imaging has contributed to a better understanding of COPD, allowing for the detection of early structural changes and the quantification of extra-pulmonary structures. Novel CT imaging techniques have provided insight into the progression of the main COPD subtypes, such as emphysema and small airway disease. This article serves as a review of new information relevant to COPD imaging. CT abnormalities, such as emphysema and loss of airways, are present even in smokers who do not meet the criteria for COPD and in those with mild-to-moderate disease. Subjects with mild-to-moderate COPD, with the highest loss of airways, also experience the highest decline in lung function. Extra-pulmonary manifestations of COPD, such as right ventricle enlargement and low muscle mass measured on CT, are associated with increased risk for all-cause mortality. CT longitudinal data has also given insight into the progression of COPD. Mechanically affected areas of lung parenchyma adjacent to emphysematous areas are associated with a greater decline in FEV₁. Subjects with the greatest percentage of small airway disease, as measured on matched inspiratory-expiratory CT scan, also present with the greatest decline in lung function.

Phenotypic characterisation of early COPD: a prospective case-control study

The phenotypic characteristics of chronic obstructive pulmonary disease (COPD) in individuals younger than 50 years of age (early COPD) are not well defined. This prospective, multicentre, case–control study sought to describe these characteristics and compare them with those of smokers (≥10 pack-years) of similar age with normal spirometry (controls).

We studied 92 cases (post-bronchodilator forced expiratory volume in 1 s (FEV₁)/forced vital capacity (FVC) <0.7) and 197 controls. Results were contrasted with participants with similar inclusion criteria recruited into the ECLIPSE and COPDGene cohorts.

Cases had moderate airflow limitation (FEV₁ 71.3±20.8%) but were often symptomatic, used healthcare resources frequently, had air trapping (residual volume 150.6±55.5% ref.), had reduced diffusing capacity (84.2±20.7% ref.) and had frequent evidence of computed tomography (CT) emphysema (61%). Of note, less than half of cases (46%) had been previously diagnosed with COPD. Interestingly, they also often reported a family history of respiratory diseases and had been hospitalised because of respiratory problems before the age of 5 years more frequently than controls (12% versus 3%, p=0.009). By and large, these observations were reproduced when available in the ECLIPSE and COPDGene cohorts.

These results show that early COPD is associated with substantial health impact and significant structural and functional abnormalities, albeit it is often not diagnosed (hence, treated). The fact that a sizeable proportion of patients with early COPD report a family history of respiratory diseases and/or early-life events (including hospitalisations before the age of 5 years) renders further support to the possibility of early-life origin of COPD.

Early COPD is associated with substantial health impact, and structural and functional abnormalities, albeit it is often not diagnosed and hence, not treated. It is frequently associated with family history of respiratory diseases and early-life events.https://bit.ly/2ZtoRkp

Combining biomarkers of clot resolution and alveolar basement membrane destruction predicts mortality in the ECLIPSE COPD cohort

BACKGROUND

Chronic obstructive pulmonary disease (COPD) is characterized by abnormal epithelial repair resulting in a hypercoagulable state with intra-alveolar accumulation of fibrin and alveolar basement membrane destruction. This study aimed to investigate if the combination of two serological biomarkers evaluating these pathological processes could improve the prediction of mortality risk compared to single biomarkers.

METHODS

Matrix metalloproteinase-mediated degradation of the type IV collagen α3 chain (C4Ma3), located in the alveolar basement membrane, and plasmin-mediated degradation of crosslinked fibrin (X-FIB), an end-product of fibrinogen, were assessed serologically in a subset of the ECLIPSE cohort (n = 982). Biomarker data were dichotomized into high versus low at the median. Cox regression and Kaplan-Meier curves were used to analyze the predictive value of having one or two high biomarkers for all-cause mortality over two years.

RESULTS

COPD participants with high levels of two biomarkers were at significantly higher risk of all-cause mortality with a hazard ratio of 7.66 (95% CI 1.75-33.48; p = 0.007) while participants with one high biomarker were not at significantly higher risk (HR 3.79 [95% CI 0.85-16.94]; p = 0.08).

CONCLUSIONS

A combination of serological biomarkers of alveolar basement membrane destruction and clot resolution was predictive of all-cause mortality in COPD. The combination of two different pathological aspects may strengthen prognostic accuracy and could be used in conjunction with clinical assessment to guide treatment decisions.

Observational studies assessing the pharmacological treatment of obstructive lung disease: strengths, challenges and considerations for study design

Randomised controlled trials (RCTs) are the gold standard for evaluating treatment efficacy in patients with obstructive lung disease. However, due to strict inclusion criteria and the conditions required for ascertaining statistical significance, the patients included typically represent as little as 5% of the general obstructive lung disease population. Thus, studies in broader patient populations are becoming increasingly important. These can be randomised effectiveness trials or observational studies providing data on real-world treatment effectiveness and safety data that complement efficacy RCTs. In this review we describe the features associated with the diagnosis of asthma and chronic obstructive pulmonary disease (COPD) in the real-world clinical practice setting. We also discuss how RCTs and observational studies have reported opposing outcomes with several treatments and inhaler devices due to differences in study design and the variations in patients recruited by different study types. Whilst observational studies are not without weaknesses, we outline recently developed tools for defining markers of quality of observational studies. We also examine how observational studies are capable of providing valuable insights into disease mechanisms and management and how they are a vital component of research into obstructive lung disease. As we move into an era of personalised medicine, recent observational studies, such as the NOVEL observational longiTudinal studY (NOVELTY), have the capacity to provide a greater understanding of the value of a personalised healthcare approach in patients in clinical practice by focussing on standardised outcome measures of patient-reported outcomes, physician assessments, airway physiology, and blood and airway biomarkers across both primary and specialist care.

The Value of FENO Measurement for Predicting Treatment Response in Patients with Acute Exacerbation of Chronic Obstructive Pulmonary Disease

BACKGROUND

Fractional exhaled nitric oxide (FENO) has been shown to be a marker of airway inflammation in various pulmonary diseases, including chronic obstructive pulmonary disease (COPD). In this study, we assessed the FENO level in patients with acute exacerbations of COPD (AECOPD) and analyzed the predictive value of the FENO level for treatment response.

METHODS

Demographic data were collected at admission. FENO, lung function, blood gases, COPD Assessment Test (CAT), and modified Medical Research Council (mMRC) scores were measured at admission and on day 7. At the second visit, the patients were asked to report their health status; scores ranged from 1 to 5, representing "much better", "slightly better", "no change", "slightly worse", and "much worse", respectively. The treatment response was evaluated based on the patient's reported health status (responders were those who reported much better and slightly better) and lung function (responders were those who presented an increase in FEV1 over 200 mL).

RESULTS

A total of 182 patients were recruited into the analysis. The FENO level positively correlated with an increase in FEV1 and FEV1% (r = 0.291, p < 0.001 and r = 0.205, p = 0.005, respectively), but negatively correlated with a decrease in the COPD Assessment Test (CAT) score (r = -0.197, p = 0.008) and patient-reported health status (rho = -0.408, p<0.001). An inverse correlation was observed between FENO concentrations at admission and the length of hospital stay. The cut-off point for differentiating responders, identified by health status, was 18 ppb, with the sensitivity being 89.7% and specificity 88.9%.

CONCLUSION

FENO levels, determined at hospital admission, are potential to predict the overall treatment response in AECOPD patients, including remission in subjective patient-reported health statuses and, also, improvements in lung function.

REGISTRY NUMBER

ChiCTR-ROC-16,009,087 (http://www.chictr.org.cn/).

Absolute Blood Eosinophil Counts to Guide Inhaled Corticosteroids Therapy Among Patients with COPD: Systematic Review and Meta-analysis

INTRODUCTION

The Global Initiative for Chronic Obstructive Lung Disease (GOLD) 2019 recommends the use of absolute blood eosinophil count as a guide for the escalation and de-escalation of inhaled corticosteroids (ICS) in the pharmacological management of patients with chronic obstructive pulmonary disease (COPD). We evaluated the risk of moderate or severe exacerbations among patients escalating and de-escalating ICS therapy by absolute blood eosinophil thresholds in this systematic review.

METHODS

Through a comprehensive literature search of Pubmed/MEDLINE, EMBASE, and clinical trial sites up to April 2019, we identified relevant studies. We used generic inverse variance method with fixed-effects estimates to compare the risk of moderate or severe exacerbations among COPD patients with elevated blood eosinophil counts exposed to inhaled corticosteroids (ICS) versus non-ICS treatments groups expressed as risk ratios.

RESULTS

Ten studies (8 randomised control trials and 2 observational studies) were included, with a total of 85,059 COPD patients. In our pooled analysis, we found an overall reduction in risk of moderate or severe exacerbations in patients with absolute blood eosinophil thresholds ranging from ≥ 100 to ≥ 340 cells/µL among patients escalating ICS (RR, 0.77, 95% CI, 0.73-0.81). For studies evaluating the effects of de-escalation of ICS on moderate to severe exacerbations using blood eosinophil thresholds of ≥ 300 to ≥ 340 cells/µL had an increased risk of moderate or severe exacerbations following the de-escalation of ICS (RR, 1.66, 95% CI, 1.31-2.10).

CONCLUSION

This study confirms the validity of the recommended absolute blood eosinophil count thresholds for the escalation and de-escalation of ICS among COPD patients. However, this recommendation is for COPD patients with prior exacerbations rather than among newly diagnosed COPD patients as observed in this study. COPD patients with current or past history of asthma represent a unique phenotypic group which should be further evaluated.

Protective effect of club cell secretory protein (CC-16) on COPD risk and progression: a Mendelian randomisation study

BACKGROUND

The anti-inflammatory pneumoprotein club cell secretory protein-16 (CC-16) is associated with the clinical expression of chronic obstructive pulmonary disease (COPD). We aimed to determine if there is a causal effect of serum CC-16 level on the risk of having COPD and/or its progression using Mendelian randomisation (MR) analysis.

METHODS

We performed a genome-wide association meta-analysis for serum CC-16 in two COPD cohorts (Lung Health Study (LHS), n=3850 and ECLIPSE, n=1702). We then used the CC-16-associated single-nucleotide polymorphisms (SNPs) as instrumental variables in MR analysis to identify a causal effect of serum CC-16 on 'COPD risk' (ie, case status in the International COPD Genetics Consortium/UK-Biobank dataset; n=35 735 COPD cases, n=222 076 controls) and 'COPD progression' (ie, annual change in forced expiratory volume in 1 s in LHS and ECLIPSE). We also determined the associations between SNPs associated with CC-16 and gene expression using n=1111 lung tissue samples from the Lung Expression Quantitative Trait Locus Study.

RESULTS

We identified seven SNPs independently associated (p<5×10^-8) with serum CC-16 levels; six of these were novel. MR analysis suggested a protective causal effect of increased serum CC-16 on COPD risk (MR estimate (SE) -0.11 (0.04), p=0.008) and progression (LHS only, MR estimate (SE) 7.40 (3.28), p=0.02). Five of the SNPs were also associated with gene expression in lung tissue (at false discovery rate <0.1) of several genes, including the CC-16-encoding gene SCGB1A1.

CONCLUSION

We have identified several novel genetic variants associated with serum CC-16 level in COPD cohorts. These genetic associations suggest a potential causal effect of serum CC-16 on the risk of having COPD and its progression, the biological basis of which warrants further investigation.

Comorbidities and Readmissions in Survivors of Acute Hypercapnic Respiratory Failure

Chronic obstructive pulmonary disease (COPD) is defined by chronic airflow obstruction, but is presently considered as a complex, heterogeneous, and multicomponent disease in which comorbidities and extrapulmonary manifestations make important contributions to disease expression. COPD-related hospital readmission. In particular frequent intensive care unit (ICU) readmissions for exacerbations represent a major challenge and place a high burden on patient outcomes and health-related quality of life, as well as on the healthcare system.In this narrative review, we first address major and often undiagnosed comorbidities associated with COPD that could have an impact on hospital readmission after an index ICU admission for acute hypercapnic respiratory failure. Some guidance for treatment is discussed. Second, we present predictors of hospital and ICU readmission and discuss various strategies to reduce such events.There is a strong rationale to detect and treat major comorbidities early after index ICU admission for acute hypercapnic respiratory failure. It still remains unclear, however, if a comprehensive and holistic approach to comorbidities in frail patients surviving hypercapnic respiratory failure can efficiently reduce the readmission rate.

Endotrophin, an extracellular hormone, in combination with neoepitope markers of von Willebrand factor improves prediction of mortality in the ECLIPSE COPD cohort

BACKGROUND

Lung epithelial damage, activation of the wound healing cascade, and remodeling of the extracellular matrix (ECM) play a major role in chronic obstructive pulmonary disease (COPD). The pro-peptide of type VI collagen has been identified as the hormone endotrophin. Endotrophin has been shown to promote fibrosis and inflammation, whereas von Willebrand factor (VWF) is a crucial part of wound healing initiation. Here, we assessed the released and activated form of VWF and endotrophin, the pro-peptide of type VI collagen, serologically to investigate their association with mortality in COPD subjects alone or in combination.

METHODS

One thousand COPD patients with 3 years of clinical follow-up from the Evaluation of COPD Longitudinally to Identify Predictive Surrogate Endpoints (ECLIPSE) cohort were included. Serum and heparin plasma were collected at 6 months and 1 year, respectively. Competitive ELISA utilizing specific monoclonal antibodies assessed endotrophin/type VI collagen formation (PRO-C6), VWF release (VWF-N), and activated VWF (VWF-A). Biomarker levels were dichotomized into high and low as defined by receiver operating characteristic (ROC) curves based on mortality data. Kaplan-Meier analysis was used to determine hazard ratios for all-cause mortality for biomarkers alone or in combination.

RESULTS

High levels of PRO-C6, VWF-A, and VWF-N have previously been shown to be individually associated with a higher risk of mortality with hazard ratios of 5.6 (95% CI 2.4-13.1), 3.7 (1.8-7.6), and 4.6 (2.2-9.6), respectively. The hazard ratios increased when combining the biomarkers: PRO-C6*VWFA 8.8 (2.8-27.7) and PRO-C6*VWFN 13.3 (5.6-32.0). Notably, PRO-C6*VWF-N increased more than 2-fold.

CONCLUSION

We demonstrated that by combining two pathological relevant aspects of COPD, tissue remodeling, and wound healing, the predictive value of biomarkers for mortality increased notably.

Eosinophilia and parasitic infestations in patients with chronic obstructive pulmonary disease

Eosinophilia may guide response to inhaled corticosteroid treatment in patients with chronic obstructive pulmonary disease (COPD). This study aimed to determine prevalence of eosinophilia and parasitic infestations in these patients. We conducted a prospective cohort study between February 2019 and January 2020 and screened 107 stable COPD patients. A total of 77 subjects (84.4% men) were included. Age was 73.8 ± 8.9 years. Forced expiratory volume in 1 s was 66.5 ± 25.5%. Smoking history was 25.9 ± 18 pack-years. Comorbidities included cardiovascular disease (57.1%). Respiratory symptoms were assessed by modified Medical Research Council dyspnea score (1.6 ± 0.8), chronic obstructive pulmonary disease Assessment Test score (9.3 ± 4.9), and 6-min walking distance (317.2 ± 135.2 m). Patients with blood eosinophil count at least 100 cells/μL were 79.2% and at least 300 cells/μL were 33.8%. Intestinal parasites were not found. Significant positive correlations were found between high blood eosinophilia and some post-bronchodilator lung function parameters. In conclusion, eosinophilic COPD was not uncommon. No intestinal parasite was found in this population. This study suggests that stool parasite exam might be omitted for routine practice.

Clinicaltrials.in.th Number: TCTR20191129002.

A cross-omics integrative study of metabolic signatures of chronic obstructive pulmonary disease

Background

Chronic obstructive pulmonary disease (COPD) is a common lung disorder characterized by persistent and progressive airflow limitation as well as systemic changes. Metabolic changes in blood may help detect COPD in an earlier stage and predict prognosis.

Methods

We conducted a comprehensive study of circulating metabolites, measured by proton Nuclear Magnetic Resonance Spectroscopy, in relation with COPD and lung function. The discovery sample consisted of 5557 individuals from two large population-based studies in the Netherlands, the Rotterdam Study and the Erasmus Rucphen Family study. Significant findings were replicated in 12,205 individuals from the Lifelines-DEEP study, FINRISK and the Prospective Investigation of the Vasculature in Uppsala Seniors (PIVUS) studies. For replicated metabolites further investigation of causality was performed, utilizing genetics in the Mendelian randomization approach.

Results

There were 602 cases of COPD and 4955 controls used in the discovery meta-analysis. Our logistic regression results showed that higher levels of plasma Glycoprotein acetyls (GlycA) are significantly associated with COPD (OR = 1.16, P = 5.6 × 10^− 4 in the discovery and OR = 1.30, P = 1.8 × 10^− 6 in the replication sample). A bi-directional two-sample Mendelian randomization analysis suggested that circulating blood GlycA is not causally related to COPD, but that COPD causally increases GlycA levels. Using the prospective data of the same sample of Rotterdam Study in Cox-regression, we show that the circulating GlycA level is a predictive biomarker of COPD incidence (HR = 1.99, 95%CI 1.52–2.60, comparing those in the highest and lowest quartile of GlycA) but is not significantly associated with mortality in COPD patients (HR = 1.07, 95%CI 0.94–1.20).

Conclusions

Our study shows that circulating blood GlycA is a biomarker of early COPD pathology.

Cost-Effectiveness Analysis of a Once-Daily Single-Inhaler Triple Therapy for Patients with Chronic Obstructive Pulmonary Disease (COPD) Using the FULFIL Trial: A Spanish Perspective

Purpose

To evaluate the cost-effectiveness of once-daily fluticasone furoate/umeclidinium/vilanterol (FF/UMEC/VI) vs twice-daily budesonide/formoterol (BUD/FOR) in patients with symptomatic chronic obstructive pulmonary disease (COPD) at risk of exacerbations, from the Spanish National Healthcare System perspective.

Patients and Methods

The validated GALAXY-COPD model was used to simulate disease progression and predict healthcare costs, quality-adjusted life years (QALYs), and incremental cost-effectiveness ratios (ICERs) over a 3-year time horizon for a Spanish population. Patient characteristics from published literature were supplemented by data from FULFIL (NCT02345161), which compared FF/UMEC/VI vs BUD/FOR in patients with symptomatic COPD at risk of exacerbations. Treatment effects, extrapolated to 3 years, were based on Week 24 results in the FULFIL intent-to-treat population, including change in forced expiratory volume in 1 second, St. George’s Respiratory Questionnaire score, and exacerbation rates. Treatment, exacerbations, and COPD management costs (2019€) were informed by Spanish public sources and published literature. A 3% discount rate for costs and benefits was applied. One-way sensitivity and scenario analyses, and probabilistic sensitivity analysis (PSA), were performed.

Results

FF/UMEC/VI treatment led to fewer moderate and severe exacerbations (2.126 and 0.306, respectively) vs BUD/FOR (2.608 and 0.515, respectively), with a mean incremental cost of €69 and gain of 0.107 QALYs, which resulted in an ICER of €642 per QALY gained. In sensitivity analyses, the ICER was most sensitive to treatment effect variations in exacerbations and healthcare resource utilization/event costs. Overall, 95% of 1000 PSA simulations resulted in an ICER less than €11,000 per QALY gained for FF/UMEC/VI vs BUD/FOR, confirming robustness of the results. The probability of FF/UMEC/VI being cost-effective vs BUD/FOR was 100% at a willingness-to-pay threshold of €30,000 per QALY gained.

Conclusion

At the accepted Spanish ICER threshold of €30,000, FF/UMEC/VI represents a cost-effective treatment option vs BUD/FOR in patients with symptomatic COPD at risk of exacerbations.

Blood neutrophil counts are associated with exacerbation frequency and mortality in COPD

BACKGROUND

Identifying patients with COPD at increased risk of poor outcomes is challenging due to disease heterogeneity. Potential biomarkers need to be readily available in real-life clinical practice. Blood eosinophil counts are widely studied but few studies have examined the prognostic value of blood neutrophil counts (BNC).

METHODS

In a large population-based COPD registry in the East of Scotland (TARDIS: Tayside Allergic and Respiratory Disease Information System), BNC were compared to measures of disease severity and mortality for up to 15 years follow-up. Potential mechanisms of disease modification by BNC were explored in a nested microbiome substudy.

RESULTS

178,120 neutrophil counts were obtained from 7220 people (mean follow up 9 years) during stable disease periods. Median BNC was 5200cells/μL (IQR 4000-7000cells/μL). Mortality rates among the 34% of patients with elevated BNCs (defined as 6000-15000cells/μL) at the study start were 80% higher (14.0/100 person years v 7.8/100py, P < 0.001) than those with BNC in the normal range (2000-6000cells/μL). People with elevated BNC were more likely to be classified as GOLD D (46% v 33% P < 0.001), have more exacerbations (mean 2.3 v 1.3/year, P < 0.001), and were more likely to have severe exacerbations (13% vs. 5%, P < 0.001) in the following year. Eosinophil counts were much less predictive of these outcomes. In a sub-cohort (N = 276), patients with elevated BNC had increased relative abundance of Proteobacteria and reduced microbiome diversity.

CONCLUSION

High BNC may provide a useful indicator of risk of exacerbations and mortality in COPD patients.

Chronic obstructive pulmonary disease and related phenotypes: polygenic risk scores in population-based and case-control cohorts

BACKGROUND

Genetic factors influence chronic obstructive pulmonary disease (COPD) risk, but the individual variants that have been identified have small effects. We hypothesised that a polygenic risk score using additional variants would predict COPD and associated phenotypes.

METHODS

We constructed a polygenic risk score using a genome-wide association study of lung function (FEV1 and FEV1/forced vital capacity [FVC]) from the UK Biobank and SpiroMeta. We tested this polygenic risk score in nine cohorts of multiple ethnicities for an association with moderate-to-severe COPD (defined as FEV1/FVC <0·7 and FEV1 <80% of predicted). Associations were tested using logistic regression models, adjusting for age, sex, height, smoking pack-years, and principal components of genetic ancestry. We assessed predictive performance of models by area under the curve. In a subset of studies, we also studied quantitative and qualitative CT imaging phenotypes that reflect parenchymal and airway pathology, and patterns of reduced lung growth.

FINDINGS

The polygenic risk score was associated with COPD in European (odds ratio [OR] per SD 1·81 [95% CI 1·74-1·88] and non-European (1·42 [1·34-1·51]) populations. Compared with the first decile, the tenth decile of the polygenic risk score was associated with COPD, with an OR of 7·99 (6·56-9·72) in European ancestry and 4·83 (3·45-6·77) in non-European ancestry cohorts. The polygenic risk score was superior to previously described genetic risk scores and, when combined with clinical risk factors (ie, age, sex, and smoking pack-years), showed improved prediction for COPD compared with a model comprising clinical risk factors alone (AUC 0·80 [0·79-0·81] vs 0·76 [0·75-0·76]). The polygenic risk score was associated with CT imaging phenotypes, including wall area percent, quantitative and qualitative measures of emphysema, local histogram emphysema patterns, and destructive emphysema subtypes. The polygenic risk score was associated with a reduced lung growth pattern.

INTERPRETATION

A risk score comprised of genetic variants can identify a small subset of individuals at markedly increased risk for moderate-to-severe COPD, emphysema subtypes associated with cigarette smoking, and patterns of reduced lung growth.

FUNDING

US National Institutes of Health, Wellcome Trust.

Fractional Exhaled Nitric Oxide as an Inflammatory Biomarker in Chronic Obstructive Pulmonary Disease (COPD) with or without Concurrent Diagnosis of Asthma: The Canadian Cohort Obstructive Lung Disease (CanCOLD)

We studied whether fractional exhaled nitric oxide (F _ENO) can differentiate chronic obstructive pulmonary disease (COPD) with concurrent diagnosis of asthma from COPD-only as well as its ability to predict disease severity and progression. This study was embedded in the Canadian Cohort Obstructive Lung Disease (CanCOLD). Subjects of ≥40 years old completed F _ENO measurements were subdivided into four groups, including COPD (N = 86 [COPD-only (N = 35) and COPD with concurrent diagnosis of asthma (N = 51)], healthy (N = 72), and at risk (N = 151). Three of the most common clinical definitions were used for characterizing COPD with concurrent diagnosis of asthma: 1) atopy and self-reported physician diagnosis of asthma, 2) ≥12% and ≥200 ml post-bronchodilator FEV1; 3) self-reported physician diagnosis of asthma. F _ENO values were classified using quartiles and the American Thoracic Society (ATS) guideline 2011. Compared to COPD-only, more COPD with concurrent diagnosis of asthma had a significant F _ENO50 level of [Formula: see text] 33.5 ppb (fourth quartile) than COPD-only (p = 0.045, 0.011, and 0.006, for definition 1, 2, and 3, respectively). Considering the ATS guideline 2011, fewer COPD with concurrent diagnosis of asthma had F _ENO50 < 25 than COPD-only, which was statistically significant with definition 1 and 3 (p = 0.038 and 0.026, respectively). F _ENO as a biomarker has the potential to be used as a complementary value for differentiating COPD with concurrent diagnosis of asthma from COPD-only. Further studies should be conducted on validated definitions of COPD with concurrent diagnosis of asthma, which may include a reference to the type of airway inflammation in addition to the clinical definition.

Increased Airway Wall Thickness in Interstitial Lung Abnormalities and Idiopathic Pulmonary Fibrosis

RATIONALE

There is increasing evidence that aberrant processes occurring in the airways may precede the development of idiopathic pulmonary fibrosis (IPF); however, there has been no prior confirmatory data derived from imaging studies.

OBJECTIVES

To assess quantitative measures of airway wall thickness (AWT) in populations characterized for interstitial lung abnormalities (ILA) and for IPF.

METHODS

Computed tomographic imaging of the chest and measures of AWT were available for 6,073, 615, 1,167, and 38 participants from COPDGene (Genetic Epidemiology of COPD study), ECLIPSE (Evaluation of COPD Longitudinally to Identify Predictive Surrogate Endpoints study), and the Framingham Heart Study (FHS) and in patients with IPF from the Brigham and Women's Hospital Herlihy Registry, respectively. To evaluate these associations, we used multivariable linear regression to compare a standardized measure of AWT (the square root of AWT for airways with an internal perimeter of 10 mm [Pi10]) and characterizations of ILA and IPF by computed tomographic imaging of the chest.

RESULTS

In COPDGene, ECLIPSE, and FHS, research participants with ILA had increased measures of Pi10 compared with those without ILA. Patients with IPF had mean measures of Pi10 that were even greater than those noted in research participants with ILA. After adjustment for important covariates (e.g., age, sex, race, body mass index, smoking behavior, and chronic obstructive pulmonary disease severity when appropriate), research participants with ILA had increased measures of Pi10 compared with those without ILA (0.03 mm in COPDGene, 95% confidence interval [CI], 0.02-0.03; P < 0.001; 0.02 mm in ECLIPSE, 95% CI, 0.005-0.04; P = 0.01; 0.07 mm in FHS, 95% CI, 0.01-0.1; P = 0.01). Compared with COPDGene participants without ILA older than 60 years of age, patients with IPF were also noted to have increased measures of Pi10 (2.0 mm, 95% CI, 2.0-2.1; P < 0.001). Among research participants with ILA, increases in Pi10 were correlated with reductions in lung volumes in some but not all populations.

CONCLUSIONS

These results demonstrate that measurable increases in AWT are consistently noted in research participants with ILA and in patients with IPF. These findings suggest that abnormalities of the airways may play a role in, or be correlated with, early pathogenesis of pulmonary fibrosis.

Measuring disease activity in COPD: is clinically important deterioration the answer?

Given the heterogeneity of chronic obstructive pulmonary disease (COPD), personalized clinical management is key to optimizing patient outcomes. Important treatment goals include minimizing disease activity and preventing disease progression; however, quantification of these components remains a challenge. Growing evidence suggests that decline over time in forced expiratory volume in 1 s (FEV1), traditionally the key marker of disease progression, may not be sufficient to fully determine deterioration across COPD populations. In addition, there is a lack of evidence showing that currently available multidimensional COPD indexes improve clinical decision-making, treatment, or patient outcomes. The composite clinically important deterioration (CID) endpoint was developed to assess disease worsening by detecting early deteriorations in lung function (measured by FEV1), health status (assessed by the St George's Respiratory Questionnaire), and the presence of exacerbations. Post hoc and prospective analyses of clinical trial data have confirmed that the multidimensional composite CID endpoint better predicts poorer medium-term outcomes compared with any single CID component alone, and that it can demonstrate differences in treatment efficacy in short-term trials. Given the widely acknowledged need for an individualized holistic approach to COPD management, monitoring short-term CID has the potential to facilitate early identification of suboptimal treatment responses and patients at risk of increased disease progression. CID monitoring may lead to better-informed clinical management decisions and potentially improved prognosis.

Role of the Bronchodilator Test Defined by the Forced Vital Capacity in Chronic Obstructive Pulmonary Disease Phenotyping

Purpose

In clinical practice, some chronic obstructive pulmonary disease (COPD) patients experienced a remarkable increase in forced vital capacity (FVC) after bronchodilator administration, whereas forced expiratory volume in the first second (FEV1) remains substantially unchanged. We assume this may relate to airway inflammatory type. We aim to analyze the clinical characteristics and explore the usefulness of the bronchodilator test, especially FVC, in this new COPD phenotype.

Patients and Methods

A total of 346 COPD patients with exacerbation who underwent bronchodilator tests, fractional exhaled nitric oxide (FeNO) measurements and blood eosinophil counts were analyzed. The characteristics, FeNO levels, and blood eosinophil counts were compared between patients with and without significant bronchodilator responsiveness in terms of FVC.

Results

Patients with significant FVC responsiveness displayed poorer lung function and higher FeNO levels compared with those without considerable FVC responsiveness (Z= −5.042 to −0.375, p=0.000–0.022). There is a discernible linear relationship between FeNO levels and FVC responsiveness to bronchodilator use (r=0.251, P=0.001). The application of bronchodilator responsiveness of FVC for detecting high FeNO levels in COPD patients exhibited relatively high sensitivity (61.8%) and specificity (86.7%).

Conclusion

We demonstrated that COPD patients with significant FVC responsiveness had higher FeNO levels than non-responders and established a simple method for detecting high FeNO values. FVC responders may be identified as a separate group of COPD patients.

Evolving Concepts in Chronic Obstructive Pulmonary Disease Blood-Based Biomarkers

In recent years, there has been a great deal of interest in the identification and validation of blood-based biomarkers for clinical use in chronic obstructive pulmonary disease (COPD). We now have panels of blood biomarkers that potentially hold great promise as they show statistically significant associations with COPD, but biomarkers for the diagnosis of COPD remain elusive. In fact, they are yet to demonstrate sufficient accuracy to be accepted in clinical use, and many are not specific to COPD but more related to inflammation (e.g. interleukin-6) or associated with other chronic diseases such as diabetes (e.g. soluble receptor for advanced glycation endproducts [sRAGE]). Although no single blood-based biomarker has demonstrated clinical utility for either the diagnosis or progression of COPD, it has been suggested that combinations of individual markers may provide important diagnostic or prognostic information; however, the interpretation of COPD biomarker results still requires thought and many questions remain unanswered.

Disease Progression Modeling in Chronic Obstructive Pulmonary Disease

Rationale: The decades-long progression of chronic obstructive pulmonary disease (COPD) renders identifying different trajectories of disease progression challenging.Objectives: To identify subtypes of patients with COPD with distinct longitudinal progression patterns using a novel machine-learning tool called "Subtype and Stage Inference" (SuStaIn) and to evaluate the utility of SuStaIn for patient stratification in COPD.Methods: We applied SuStaIn to cross-sectional computed tomography imaging markers in 3,698 Global Initiative for Chronic Obstructive Lung Disease (GOLD) 1-4 patients and 3,479 controls from the COPDGene (COPD Genetic Epidemiology) study to identify subtypes of patients with COPD. We confirmed the identified subtypes and progression patterns using ECLIPSE (Evaluation of COPD Longitudinally to Identify Predictive Surrogate Endpoints) data. We assessed the utility of SuStaIn for patient stratification by comparing SuStaIn subtypes and stages at baseline with longitudinal follow-up data.Measurements and Main Results: We identified two trajectories of disease progression in COPD: a "Tissue→Airway" subtype (n = 2,354, 70.4%), in which small airway dysfunction and emphysema precede large airway wall abnormalities, and an "Airway→Tissue" subtype (n = 988, 29.6%), in which large airway wall abnormalities precede emphysema and small airway dysfunction. Subtypes were reproducible in ECLIPSE. Baseline stage in both subtypes correlated with future FEV₁/FVC decline (r = -0.16 [P < 0.001] in the Tissue→Airway group; r = -0.14 [P = 0.011] in the Airway→Tissue group). SuStaIn placed 30% of smokers with normal lung function at elevated stages, suggesting imaging changes consistent with early COPD. Individuals with early changes were 2.5 times more likely to meet COPD diagnostic criteria at follow-up.Conclusions: We demonstrate two distinct patterns of disease progression in COPD using SuStaIn, likely representing different endotypes. One third of healthy smokers have detectable imaging changes, suggesting a new biomarker of "early COPD."

Validation of a method to assess emphysema severity by spirometry in the COPDGene study

Background

Standard spirometry cannot identify the predominant mechanism underlying airflow obstruction in COPD, namely emphysema or airway disease. We aimed at validating a previously developed methodology to detect emphysema by mathematical analysis of the maximal expiratory flow-volume (MEFV) curve in standard spirometry.

Methods

From the COPDGene population we selected those 5930 subjects with MEFV curve and inspiratory-expiratory CT obtained on the same day. The MEFV curve descending limb was fit real-time using forced vital capacity (FVC), peak expiratory flow, and forced expiratory flows at 25, 50 and 75% of FVC to derive an emphysema severity index (ESI), expressed as a continuous positive numeric parameter ranging from 0 to 10. According to inspiratory CT percent lung attenuation area below − 950 HU we defined three emphysema severity subgroups (%LAA_-950insp < 6, 6–14, ≥14). By co-registration of inspiratory-expiratory CT we quantified persistent (%pLDA) and functional (%fLDA) low-density areas as CT metrics of emphysema and airway disease, respectively.

Results

ESI differentiated CT emphysema severity subgroups increasing in parallel with GOLD stages (p < .001), but with high variability within each stage. ESI had significantly higher correlations (p < .001) with emphysema than with airway disease CT metrics, explaining 67% of %pLDA variability. Conversely, standard spirometric variables (FEV₁, FEV₁/FVC) had significantly lower correlations than ESI with emphysema CT metrics and did not differentiate between emphysema and airways CT metrics.

Conclusions

ESI adds to standard spirometry the power to discriminate whether emphysema is the predominant mechanism of airway obstruction. ESI methodology has been validated in the large multiethnic population of smokers of the COPDGene study and therefore it could be applied for clinical and research purposes in the general population of smokers, using a readily available online website.

Heme metabolism genes Downregulated in COPD Cachexia

INTRODUCTION

Cachexia contributes to increased mortality and reduced quality of life in Chronic Obstructive Pulmonary Disease (COPD) and may be associated with underlying gene expression changes. Our goal was to identify differential gene expression signatures associated with COPD cachexia in current and former smokers.

METHODS

We analyzed whole-blood gene expression data from participants with COPD in a discovery cohort (COPDGene, N = 400) and assessed replication (ECLIPSE, N = 114). To approximate the consensus definition using available criteria, cachexia was defined as weight-loss > 5% in the past 12 months or low body mass index (BMI) (< 20 kg/m2) and 1/3 criteria: decreased muscle strength (six-minute walk distance < 350 m), anemia (hemoglobin < 12 g/dl), and low fat-free mass index (FFMI) (< 15 kg/m2 among women and < 17 kg/m2 among men) in COPDGene. In ECLIPSE, cachexia was defined as weight-loss > 5% in the past 12 months or low BMI and 3/5 criteria: decreased muscle strength, anorexia, abnormal biochemistry (anemia or high c-reactive protein (> 5 mg/l)), fatigue, and low FFMI. Differential gene expression was assessed between cachectic and non-cachectic subjects, adjusting for age, sex, white blood cell counts, and technical covariates. Gene set enrichment analysis was performed using MSigDB.

RESULTS

The prevalence of COPD cachexia was 13.7% in COPDGene and 7.9% in ECLIPSE. Fourteen genes were differentially downregulated in cachectic versus non-cachectic COPD patients in COPDGene (FDR < 0.05) and ECLIPSE (FDR < 0.05).

DISCUSSION

Several replicated genes regulating heme metabolism were downregulated among participants with COPD cachexia. Impaired heme biosynthesis may contribute to cachexia development through free-iron buildup and oxidative tissue damage.

Towards large-scale case-finding: training and validation of residual networks for detection of chronic obstructive pulmonary disease using low-dose CT

BACKGROUND

Chronic obstructive pulmonary disease (COPD) is underdiagnosed in the community. Thoracic CT scans are widely used for diagnostic and screening purposes for lung cancer. In this proof-of-concept study, we aimed to evaluate a software pipeline for the automated detection of COPD, based on deep learning and a dataset of low-dose CTs that were performed for early detection of lung cancer.

METHODS

We examined the use of deep residual networks, a type of artificial residual network, for the automated detection of COPD. Three versions of the residual networks were independently trained to perform COPD diagnosis using random subsets of CT scans collected from the PanCan study, which enrolled ex-smokers and current smokers at high risk of lung cancer, and evaluated the networks using three-fold cross-validation experiments. External validation was performed using 2153 CT scans acquired from a separate cohort of individuals with COPD in the ECLIPSE study. Spirometric data were used to define COPD, with stages defined according to the GOLD criteria.

FINDINGS

The best performing networks achieved an area under the receiver operating characteristic curve (AUC) of 0·889 (SD 0·017) in three-fold cross-validation experiments. When the same set of networks was applied to the ECLIPSE cohort without any modifications to the trained models, they achieved an AUC of 0·886 (0·017), a positive predictive value of 0·847 (0·056), and a negative predictive value of 0·755 (0·097), which is a greater performance than the best quantitative CT measure, the percentage of lung volumes of less than or equal to -950 Hounsfield units (AUC 0·742).

INTERPRETATION

Our proposed approach could identify patients with COPD among ex-smokers and current smokers without a previous diagnosis of COPD, with clinically acceptable performance. The use of deep residual networks on chest CT scans could be an effective case-finding tool for COPD detection and diagnosis, particularly in ex-smokers and current smokers who are being screened for lung cancer.

FUNDING

Data Science Institute, University of British Columbia; Canadian Institutes of Health Research.

Common and Rare Variants Genetic Association Analysis of Cigarettes per Day Among Ever-Smokers in Chronic Obstructive Pulmonary Disease Cases and Controls

INTRODUCTION

Cigarette smoking is a major environmental risk factor for many diseases, including chronic obstructive pulmonary disease (COPD). There are shared genetic influences on cigarette smoking and COPD. Genetic risk factors for cigarette smoking in cohorts enriched for COPD are largely unknown.

METHODS

We performed genome-wide association analyses for average cigarettes per day (CPD) across the Genetic Epidemiology of COPD (COPDGene) non-Hispanic white (NHW) (n = 6659) and African American (AA) (n = 3260), GenKOLS (the Genetics of Chronic Obstructive Lung Disease) (n = 1671), and ECLIPSE (the Evaluation of COPD Longitudinally to Identify Predictive Surrogate Endpoints) (n = 1942) cohorts. In addition, we performed exome array association analyses across the COPDGene NHW and AA cohorts. We considered analyses across the entire cohort and stratified by COPD case-control status.

RESULTS

We identified genome-wide significant associations for CPD on chromosome 15q25 across all cohorts (lowest p = 1.78 × 10-15), except in the COPDGene AA cohort alone. Previously reported associations on chromosome 19 had suggestive and directionally consistent associations (RAB4, p = 1.95 × 10-6; CYP2A7, p = 7.50 × 10-5; CYP2B6, p = 4.04 × 10-4). When we stratified by COPD case-control status, single nucleotide polymorphisms on chromosome 15q25 were nominally associated with both NHW COPD cases (β = 0.11, p = 5.58 × 10-4) and controls (β = 0.12, p = 3.86 × 10-5) For the gene-based exome array association analysis of rare variants, there were no exome-wide significant associations. For these previously replicated associations, the most significant results were among COPDGene NHW subjects for CYP2A7 (p = 5.2 × 10-4).

CONCLUSIONS

In a large genome-wide association study of both common variants and a gene-based association of rare coding variants in ever-smokers, we found genome-wide significant associations on chromosome 15q25 with CPD for common variants, but not for rare coding variants. These results were directionally consistent among COPD cases and controls.

IMPLICATIONS

We examined both common and rare coding variants associated with CPD in a large population of heavy smokers with and without COPD of NHW and AA descent. We replicated genome-wide significant associations on chromosome 15q25 with CPD for common variants among NHW subjects, but not for rare variants. We demonstrated for the first time that common variants on chromosome 15q25 associated with CPD are similar among COPD cases and controls. Previously reported associations on chromosome 19 showed suggestive and directionally consistent associations among common variants (RAB4, CYP2A7, and CYP2B6) and for rare variants (CYP2A7) among COPDGene NHW subjects. Although the genetic effect sizes for these single nucleotide polymorphisms on chromosome 15q25 are modest, we show that this creates a substantial smoking burden over the lifetime of a smoker.

Inter- and intra-software reproducibility of computed tomography lung density measurements

PURPOSE

Multiple commercial, open-source, and academic software tools exist for objective quantification of lung density in computed tomography (CT) images. The purpose of this study was to evaluate the intersoftware reproducibility of CT lung density measurements.

METHODS

Computed tomography images from 50 participants from the COPDGene^TM cohort study were randomly selected for analysis; n = 10 participants across each global initiative for chronic obstructive lung disease (GOLD) grade (GOLD 0-IV). Academic-based groups (n = 4) and commercial vendors (n = 4) participated anonymously to generate CT lung density measurements using their software tools. Computed tomography total lung volume (TLV), percentage of the low attenuation areas in the lung with Hounsfield unit (HU) values below -950HU (LAA₉₅₀ ), and the HU value corresponding to the 15th percentile on the parenchymal density histogram (Perc15) were included in the analysis. The intersoftware bias and reproducibility coefficient (RDC) was generated with and without quality assurance (QA) for manual correction of the lung segmentation; intrasoftware bias and RDC was also generated by repeated measurements on the same images.

RESULTS

Intersoftware mean bias was within ±0.22 mL, ±0.46%, and ±0.97 HU for TLV, LAA₉₅₀ and Perc15, respectively. The RDC was 0.35 L, 1.2% and 1.8 HU for TLV, LAA₉₅₀ and Perc15, respectively. Intersoftware RDC remained unchanged following QA: 0.35 L, 1.2% and 1.8 HU for TLV, LAA₉₅₀ and Perc15, respectively. All software investigated had an intrasoftware RDC of 0. The RDC was comparable for TLV, LAA₉₅₀ and Perc15 measurements, respectively, for academic-based groups/commercial vendor-based software tools: 0.39 L/0.32 L, 1.2%/1.2%, and 1.7 HU/1.6 HU. Multivariable regression analysis showed that academic-based software tools had greater within-subject standard deviation of TLV than commercial vendors, but no significant differences between academic and commercial groups were found for LAA₉₅₀ or Perc15 measurements.

CONCLUSIONS

Computed tomography total lung volume and lung density measurement bias and reproducibility was reported across eight different software tools. Bias was negligible across vendors, reproducibility was comparable for software tools generated by academic-based groups and commercial vendors, and segmentation QA had negligible impact on measurement variability between software tools. In summary, results from this study report the amount of additional measurement variability that should be accounted for when using different software tools to measure lung density longitudinally with well-standardized image acquisition protocols. However, intrasoftware reproducibility was deterministic for all cases so use of the same software tool to reduce variability for serial studies is highly recommended.

The association of silicosis severity with pectoralis major muscle and subcutaneous fat volumes and the pulmonary artery/aorta ratio evaluated by CT

PURPOSE

Silicosis is an incurable occupational disease that sometimes rapidly progresses with fatal outcomes. We aimed to evaluate the association between disease severity and the change in the pectoralis major muscle volume (PMV), subcutaneous fat volume (SFV), and the pulmonary artery/aorta (P/Ao) ratio in patients with silicosis using computed tomography (CT).

METHODS

The study included 41 male silicosis patients and 41 control group subjects with available chest CT images. Using dedicated software, we measured PMV and SFV from the axial CT images. We calculated the P/Ao ratio and obtained body mass index (BMI) and forced expiratory volume/forced vital capacity (FEV1/FVC) results from hospital records. We used the chest X-ray profusion score according to the International Labor Organization (ILO) classification to evaluate the severity of the silicosis.

RESULTS

The mean age was 33.5±4.4 and 34.7±4.7 years in the silicotic and control groups, respectively. The mean BMI, PMV, SFV, and P/Ao values significantly differed between the study and control groups (P = 0.0009, P < 0.0001, P < 0.0001, and P = 0.0029, respectively). According to the ILO classification, there were 12 silicosis patients in category 1, 13 in category 2, and 16 in category 3. A significant difference was found between disease categories in terms of PMV, SFV, P/Ao, BMI, and FEV1/FVC values (P = 0.0425, P = 0.0341, P = 0.0002, P = 0.0492, and P = 0.0004, respectively).

CONCLUSION

Disease severity had a stronger association with decreased PMV and SFV and increased P/Ao ratios than BMI in patients with silicosis caused by denim sandblasting. Thus, CT evaluation might be a useful indicator of disease severity.

Increased von Willebrand Factor Processing in COPD, Reflecting Lung Epithelium Damage, Is Associated with Emphysema, Exacerbations and Elevated Mortality Risk

Background

Chronic obstructive pulmonary disease (COPD) is characterized by chronic inflammation and lung tissue deterioration. Given the high vascularity of the lung, von Willebrand factor (VWF), a central component of wound healing initiation, has previously been assessed in COPD. VWF processing, which is crucial for regulating the primary response of wound healing, has not been assessed directly. Therefore, this study aimed to characterize wound healing initiation in COPD using dynamic VWF-processing biomarkers and to evaluate how these relate to disease severity and mortality.

Methods

A cross-sectional analysis of plasma samples from the ECLIPSE study collected at year 1 from moderate to very severe COPD subjects (GOLD 2-4, n=984) was performed. We applied competitive neo-epitope ELISAs specifically targeting the formation of and ADAMTS13-processed form of VWF, VWF-N and VWF-A, respectively.

Results

VWF-A and VWF-N were significantly increased (VWF-N, p=0.01; VWF-A, p=0.0001) in plasma of symptomatic (mMRC score ≥2) compared to asymptomatic/mild symptomatic COPD subjects. Increased VWF-N and VWF-A levels were specifically associated with emphysema (VWF-N, p<0.0001) or prior exacerbations (VWF-A, p=0.01). When dichotomized, high levels of both biomarkers were associated with increased risk of all-cause mortality (VWF-N, HR 3.5; VWF-A, HR 2.64).

Conclusion

We demonstrate that changes in VWF processing were related to different pathophysiological aspects of COPD. VWF-N relates to the chronic condition of emphysema, while VWF-A was associated with the more acute events of exacerbations. This study indicates that VWF-A and VWF-N may be relevant markers for characterization of disease phenotype and are associated with mortality in COPD.

Study Identifier

NCT00292552; GSK study code SCO104960.

Pulmonary Imaging Phenotypes of Chronic Obstructive Pulmonary Disease Using Multiparametric Response Maps

Background Pulmonary imaging of chronic obstructive pulmonary disease (COPD) has focused on CT or MRI measurements, but these have not been evaluated in combination. Purpose To generate multiparametric response map (mPRM) measurements in ex-smokers with or without COPD by using volume-matched CT and hyperpolarized helium 3 (³He) MRI. Materials and Methods In this prospective study (https://clinicaltrials.gov, NCT02279329), participants underwent MRI and CT and completed pulmonary function tests, questionnaires, and the 6-minute walk test between December 2010 and January 2019. Disease status was determined by using Global initiative for chronic Obstructive Lung Disease (GOLD) criteria. The mPRM voxel values were generated by using co-registered MRI and CT labels. Kruskal-Wallis and Bonferroni tests were used to determine differences across disease severity, and correlations were determined by using Spearman coefficients. Results A total of 175 ex-smokers (mean age, 69 years ± 9 [standard deviation], 108 men) with or without COPD were evaluated. Ex-smokers without COPD had a larger fraction of normal mPRM voxels (60% vs 37%, 20%, and 7% for GOLD I, II, and III/IV disease, respectively; all P ≤ .001) and a smaller fraction of abnormal voxels, including small airways disease (normal CT, not ventilated: 5% vs 6% [not significant], 11%, and 19% [P ≤ .001 for both] for GOLD I, II, and III/IV disease, respectively) and mild emphysema (normal CT, abnormal apparent diffusion coefficient [ADC]: 33% vs 54%, 56%, and 54% for GOLD I, II, and III/IV disease respectively; all P ≤ .001). Normal mPRM measurements were positively correlated with forced expiratory volume in 1 second (FEV₁) (r = 0.65, P < .001), the FEV₁-to-forced vital capacity ratio (r = 0.81, P < .001), and diffusing capacity (r = 0.75, P < .001) and were negatively correlated with worse quality of life (r = -0.48, P < .001). Abnormal mPRM measurements of small airways disease (normal CT, not ventilated) and mild emphysema (normal CT, abnormal ADC) were negatively correlated with FEV₁ (r = -0.65 and -0.42, respectively; P < .001) and diffusing capacity (r = -0.53 and -0.60, respectively; P < .001) and were positively correlated with worse quality of life (r = 0.45 and r = 0.33, respectively; P < .001), both of which were present in ex-smokers without COPD. Conclusion Multiparametric response maps revealed two abnormal structure-function results related to emphysema and small airways disease, both of which were unexpectedly present in ex-smokers with normal spirometry and CT findings. © RSNA, 2020 Online supplemental material is available for this article.

Risk assessment for hospital admission in patients with COPD; a multi-centre UK prospective observational study

In chronic obstructive pulmonary disease (COPD), acute exacerbation of COPD requiring hospital admission is associated with mortality and healthcare costs. The ERICA study assessed multiple clinical measures in people with COPD, including the short physical performance battery (SPPB), a simple test of physical function with 3 components (gait speed, balance and sit-to-stand). We tested the hypothesis that SPPB score would relate to risk of hospital admissions and length of hospital stay. Data were analysed from 714 of the total 729 participants (434 men and 280 women) with COPD. Data from this prospective observational longitudinal study were obtained from 4 secondary and 1 tertiary centres from England, Scotland, and Wales. The main outcome measures were to estimate the risk of hospitalisation with acute exacerbation of COPD (AECOPD and length of hospital stay derived from hospital episode statistics (HES). In total, 291 of 714 individuals experienced 762 hospitalised AECOPD during five-year follow up. Poorer performance of SPPB was associated with both higher rate (IRR 1.08 per 1 point decrease, 95% CI 1.01 to 1.14) and increased length of stay (IRR 1.18 per 1 point decrease, 95% CI 1.10 to 1.27) for hospitalised AECOPD. For the individual sit-to-stand component of the SPPB, the association was even stronger (IRR 1.14, 95% CI 1.02 to 1.26 for rate and IRR 1.32, 95% CI 1.16 to 1.49 for length of stay for hospitalised AECOPD). The SPPB, and in particular the sit-to-stand component can both evaluate the risk of H-AECOPD and length of hospital stay in COPD. The SPPB can aid in clinical decision making and when prioritising healthcare resources.

Deep Learning Enables Automatic Classification of Emphysema Pattern at CT

BackgroundPattern of emphysema at chest CT, scored visually by using the Fleischner Society system, is associated with physiologic impairment and mortality risk.PurposeTo determine whether participant-level emphysema pattern could predict impairment and mortality when classified by using a deep learning method.Materials and MethodsThis retrospective analysis of Genetic Epidemiology of COPD (COPDGene) study participants enrolled between 2007 and 2011 included those with baseline CT, visual emphysema scores, and survival data through 2018. Participants were partitioned into nonoverlapping sets of 2407 for algorithm training, 100 for validation and parameter tuning, and 7143 for testing. A deep learning algorithm using convolutional neural network and long short-term memory architectures was trained to classify pattern of emphysema according to Fleischner criteria. Deep learning scores were compared with visual scores and clinical parameters including pulmonary function tests. Cox proportional hazard models were used to evaluate relationships between emphysema scores and survival. The algorithm was also tested by using CT and clinical data in 1962 participants enrolled in the Evaluation of COPD Longitudinally to Identify Predictive Surrogate End-points (ECLIPSE) study.ResultsA total of 7143 COPDGene participants (mean age ± standard deviation, 59.8 years ± 8.9; 3734 men and 3409 women) were evaluated. Deep learning emphysema classifications were associated with impaired pulmonary function tests, 6-minute walk distance, and St George's Respiratory Questionnaire at univariate analysis (P < .001 for each). Testing in the ECLIPSE cohort showed similar associations (P < .001). In the COPDGene test cohort, deep learning emphysema classification improved the fit of linear mixed models in the prediction of these clinical parameters compared with visual scoring (P < .001). Compared with participants without emphysema, mortality was greater in participants classified by the deep learning algorithm as having any grade of emphysema (adjusted hazard ratios were 1.5, 1.7, 2.9, 5.3, and 9.7, respectively, for trace, mild, moderate, confluent, and advanced destructive emphysema; P < .05).ConclusionDeep learning automation of the Fleischner grade of emphysema at chest CT is associated with clinical measures of pulmonary insufficiency and the risk of mortality.© RSNA, 2019Online supplemental material is available for this article.