Optimism is associated with respiratory symptoms and functional status in chronic obstructive pulmonary disease

Background

Optimism is the general belief that good things will occur in the future; optimism is modifiable by cognitive behavioral therapy (CBT). Previous studies have associated higher optimism with improved health outcomes and lower all-cause mortality.

Research question

Investigate association between optimism and disease-related characteristics in chronic obstructive pulmonary disease (COPD).

Study design and methods

Current and former smokers with/without COPD and Preserved Ratio Impaired Spirometry (PRISm) from the 10-year follow-up visit for the Genetic Epidemiology of COPD (COPDGene) study were included. Optimism was assessed at the 10-year visit using the Life Orientation Test-Revised. Models of optimism as a predictor of lung function, COPD-associated phenotypes including exacerbations, and functional assessments, were adjusted for demographic confounders, smoking status, and comorbidities.

Results

Among 1967 subjects, higher optimism was significantly associated with older age, non-Hispanic white race, marital status, quitting smoking status, absence of COPD, and absence of depression. In multivariable analysis, higher optimism was independently associated with fewer prior exacerbations of COPD (coef = − 0.037, P < 0.001). Higher optimism was also related to better MMRC scores (coef = − 0.041, P < 0.001), CAT scores (coef = − 0.391, P < 0.001), SGRQ scores (coef = − 0.958, P < 0.001), BODE index (coef = − 0.059, P < 0.001), and longer 6-min walk distance (coef = 10.227, P < 0.001). After stratification by severity of COPD, these associations with optimism were still significant in all groups. No significant association was observed for cross-sectional FEV₁ (%) or FVC (%) with optimism score.

Interpretation

Fewer exacerbations and less severe respiratory symptoms and higher functional capacity were associated with higher optimism, which may impact health outcomes in current and former smokers with and without COPD. Optimism is a modifiable trait and these results may further support a role for CBT to improve outcomes in COPD.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12931-021-01922-6.

Increased mortality associated with frequent exacerbations in COPD patients with mild-to-moderate lung function impairment, and smokers with normal spirometry

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A rapidly changing understanding of COPD: World COPD Day from the COPD Foundation

World COPD Day raises awareness about chronic obstructive pulmonary disease (COPD). COPD accounts for over 150,000 US deaths per year. A major challenge is that COPD receives only a fraction of the research funding provided to other major diseases. Control of COPD is dependent on developing new approaches to diagnose the disease earlier with a recognition of either pre-COPD or established COPD based on symptoms, lung structural change and/or loss of lung function that occurs before meeting long established criteria for a population-based definition of obstruction. Optimization of current therapies improves lung function, exercise capacity, quality of life, and survival. New pathways of disease progression are being identified creating new opportunities for development of therapies that could stop or cure this disease.

MnTE-2-PyP disrupts Staphylococcus aureus biofilms in a novel fracture model

Biofilm-associated infections in orthopedic surgery lead to worse clinical outcomes and greater morbidity and mortality. The scope of the problem encompasses infected total joints, internally fixed fractures, and implanted devices. Diagnosis is difficult. Cultures are often negative, and antibiotic treatments are ineffective. The infections resist killing by the immune system and antibiotics. The organized matrix structure of extracellular polymeric substances within the biofilm shields and protects the bacteria from identification and immune cell action. Bacteria in biofilms actively modulate their redox environment and can enhance the matrix structure by creating an oxidizing environment. We postulated that a potent redox-active metalloporphyrin MnTE-2-PyP (chemical name: manganese (II) meso-tetrakis-(N-methylpyridinium-2-yl) porphyrin) that scavenges reactive species and modulates the redox state to a reduced state, would improve the effect of antibiotic treatment for a biofilm-associated infection. An infected fracture model with a midshaft femoral osteotomy was created in C57B6 mice, internally fixed with an intramedullary 23-gauge needle and seeded with a biofilm-forming variant of Staphylococcus aureus. Animals were divided into three treatment groups: control, antibiotic alone, and combined antibioticplus MnTE-2-PyP. The combined treatment group had significantly decreased bacterial counts in harvested bone, compared with antibiotic alone. In vitro crystal violet assay of biofilm structure and corresponding nitroblue tetrazolium assay for reactive oxygen species (ROS) demonstrated that MnTE-2-PyP decreased the biofilm structure and reduced ROS in a correlated and dose-dependent manner. The biofilm structure is redox-sensitive in S. aureus and an ROS scavenger improved the effect of antibiotic therapy in model of biofilm-associated infections.

Daily Activities: The Impact of COPD and Cognitive Dysfunction

OBJECTIVE

Chronic obstructive pulmonary disease (COPD) is characterized by airflow limitation; however, pulmonary function does not fully account for patients' functional difficulties. The primary aim of the study was to determine the association between several domains of cognition and daily activity among those with COPD.

METHOD

Eighty-nine former smokers completed a neuropsychological battery including measures across multiple domains of cognition, pulmonary function measures, and daily activity questionnaires. Using a cross-sectional design, we compared daily activity between former smokers with and without COPD using two measures (St. George's Respiratory Questionnaire [SGRQ] Activity Subscale and Lawton Instrumental Activities of Daily Living [IADL] Scale) and examined the association between cognition and daily activity among those with COPD.

RESULTS

As expected, former smokers with COPD reported more difficulty than those without COPD on both activity measures (SGRQ Activity Subscale p < .001; Lawton IADL Scale p = .040). Among former smokers with COPD, poorer delayed recall was associated with more difficulty with daily activities (SGRQ Activity Subscale) (p = .038) while adjusting for severity of airflow limitation, exercise tolerance, oxygen use, dyspnea, and symptoms of anxiety and depression.

CONCLUSION

The findings suggest that cognition is associated with daily activity in patients with COPD. Future research should examine whether cognitive interventions may help to maximize patients' engagement in daily activities.

Cognitive performance is lower among individuals with overlap syndrome than in individuals with COPD or obstructive sleep apnea alone: association with carotid artery stiffness

Chronic obstructive pulmonary disease (COPD) and obstructive sleep apnea (OSA) are both independently associated with increased cardiovascular disease (CVD) risk and impaired cognitive function. It is unknown if individuals with both COPD and OSA (i.e., overlap syndrome) have greater common carotid artery (CCA) stiffness, an independent predictor of CVD risk, and lower cognitive performance than either COPD or OSA alone. Elevated CCA stiffness is associated with cognitive impairment in former smokers with and without COPD in past studies. We compared CCA stiffness and cognitive performance between former smokers with overlap syndrome, COPD only, OSA only and former smoker controls using analysis of covariance (ANCOVA) tests to adjust for age, sex, body mass index (BMI), pack years, and postbronchodilator FEV1/FVC. We also examined the association between CCA stiffness and cognitive performance among each group separately. Individuals with overlap syndrome (n = 12) had greater CCA β-stiffness index (P = 0.015) and lower executive function-processing speed (P = 0.019) than individuals with COPD alone (n = 47), OSA alone (n = 9), and former smoker controls (n = 21), differences that remained significant after adjusting for age, BMI, sex, pack years, and FEV1/FVC. Higher CCA β-stiffness index was associated with lower executive function-processing speed in individuals with overlap syndrome (r = -0.58, P = 0.047). These data suggest that CCA stiffness is greater and cognitive performance is lower among individuals with overlap syndrome compared with individuals with COPD or OSA alone and that CCA stiffening may be an underlying mechanism contributing to the lower cognitive performance observed in patients with overlap syndrome.NEW & NOTEWORTHY Previous studies have demonstrated greater carotid artery stiffness and lower cognitive function among individuals with COPD alone and OSA alone. However, the present study is the first to demonstrate that individuals that have both COPD and OSA (i.e., overlap syndrome) have greater carotid artery stiffness and lower executive function-processing speed than individuals with either disorder alone. Furthermore, among individuals with overlap syndrome greater carotid artery stiffness is associated with lower executive function-processing speed.

Enabling a learning healthcare system with automated computer protocols that produce replicable and personalized clinician actions

Clinical decision-making is based on knowledge, expertise, and authority, with clinicians approving almost every intervention-the starting point for delivery of "All the right care, but only the right care," an unachieved healthcare quality improvement goal. Unaided clinicians suffer from human cognitive limitations and biases when decisions are based only on their training, expertise, and experience. Electronic health records (EHRs) could improve healthcare with robust decision-support tools that reduce unwarranted variation of clinician decisions and actions. Current EHRs, focused on results review, documentation, and accounting, are awkward, time-consuming, and contribute to clinician stress and burnout. Decision-support tools could reduce clinician burden and enable replicable clinician decisions and actions that personalize patient care. Most current clinical decision-support tools or aids lack detail and neither reduce burden nor enable replicable actions. Clinicians must provide subjective interpretation and missing logic, thus introducing personal biases and mindless, unwarranted, variation from evidence-based practice. Replicability occurs when different clinicians, with the same patient information and context, come to the same decision and action. We propose a feasible subset of therapeutic decision-support tools based on credible clinical outcome evidence: computer protocols leading to replicable clinician actions (eActions). eActions enable different clinicians to make consistent decisions and actions when faced with the same patient input data. eActions embrace good everyday decision-making informed by evidence, experience, EHR data, and individual patient status. eActions can reduce unwarranted variation, increase quality of clinical care and research, reduce EHR noise, and could enable a learning healthcare system.

Progression of Emphysema and Small Airways Disease in Cigarette Smokers

BACKGROUND

Little is known about factors associated with emphysema progression in cigarette smokers. We evaluated factors associated with change in emphysema and forced expiratory volume in 1 second (FEV1) in participants with and without chronic obstructive pulmonary disease (COPD).

METHODS

This retrospective study included individuals participating in the COPD Genetic Epidemiology study who completed the 5-year follow-up, including inspiratory and expiratory computed tomography (CT) and spirometry. All paired CT scans were analyzed using micro-mapping, which classifies individual voxels as emphysema or functional small airway disease (fSAD). Presence and progression of emphysema and FEV1 were determined based on comparison to nonsmoker values. Logistic regression analyses were used to identify clinical parameters associated with disease progression.

RESULTS

A total of 3088 participants were included with a mean ± SD age of 60.7±8.9 years, including 72 nonsmokers. In all Global initiative for chronic Obstructive Lung Disease (GOLD) stages, the presence of emphysema at baseline was associated with emphysema progression (odds ratio [OR]: GOLD 0: 4.32; preserved ratio-impaired spirometry [PRISm]; 5.73; GOLD 1: 5.16; GOLD 2: 5.69; GOLD 3/4: 5.55; all p ≤0.01). If there was no emphysema at baseline, the amount of fSAD at baseline was associated with emphysema progression (OR for 1% increase: GOLD 0: 1.06; PRISm: 1.20; GOLD 1: 1.7; GOLD 3/4: 1.08; all p ≤ 0.03).In 1735 participants without spirometric COPD, progression in emphysema occurred in 105 (6.1%) participants and only 21 (1.2%) had progression in both emphysema and FEV1.

CONCLUSIONS

The presence of emphysema is an important predictor of emphysema progression. In patients without emphysema, fSAD is associated with the development of emphysema. In participants without spirometric COPD, emphysema progression occurred independently of FEV1 decline.

Impact of a Medical Diagnosis on Decision to Stop Smoking and Successful Smoking Cessation

Introduction

Smoking cessation counseling is a central part of the Medicare guidelines for lung cancer screening. With increasing age, many heavy smokers eventually stop smoking, however, factors influencing the decision to stop smoking are poorly understood. We postulated that declining health or physician-diagnosis of a medical condition may be associated with successful smoking cessation.

Methods

A total of 4448 current and former smokers in Phase 2 of the COPD Genetic Epidemiology (COPDGene®) study answered a question about reasons for stopping smoking. Participants were classified as successful quitters (n=3345), and unsuccessful quitters (n=1003). Reasons cited for quitting were grouped as: medical diagnoses, social factors, symptoms. Logistic modeling of factors associated with successful quitting were adjusted for age, gender, race, and education.

Results

The most common factors cited for a quit attempt by all respondents were medical diagnoses (48%), followed by social factors (47%), and respiratory symptoms (36%). Successful quitters were more likely to be older, male, and non-Hispanic White. An adjusted model found increased age, White race, education beyond high school, and male sex favored successful quitting while the cited medical diagnoses, social factors, and "other" reasons were associated with unsuccessful quitting. Fagerstrom Nicotine Dependence scores were ³ 5 in 54% of the unsuccessful group compared to 45% for successful quitters(p<0.0001) suggesting some increased nicotine dependence in the unsuccessful quitters.

Conclusions

Medical diagnosis was the most common factor cited for considering a quit attempt by both successful and unsuccessful quitters; however, successful quitting was influenced by demographic factors and potentially the severity of nicotine dependence.

A Risk Prediction Model for Mortality Among Smokers in the COPDGene® Study

BACKGROUND

Risk factor identification is a proven strategy in advancing treatments and preventive therapy for many chronic conditions. Quantifying the impact of those risk factors on health outcomes can consolidate and focus efforts on individuals with specific high-risk profiles. Using multiple risk factors and longitudinal outcomes in 2 independent cohorts, we developed and validated a risk score model to predict mortality in current and former cigarette smokers.

METHODS

We obtained extensive data on current and former smokers from the COPD Genetic Epidemiology (COPDGene®) study at enrollment. Based on physician input and model goodness-of-fit measures, a subset of variables was selected to fit final Weibull survival models separately for men and women. Coefficients and predictors were translated into a point system, allowing for easy computation of mortality risk scores and probabilities. We then used the SubPopulations and InteRmediate Outcome Measures In COPD Study (SPIROMICS) cohort for external validation of our model.

RESULTS

Of 9867 COPDGene participants with standard baseline data, 17.6% died over 10 years of follow-up, and 9074 of these participants had the full set of baseline predictors (standard plus 6-minute walk distance and computed tomography variables) available for full model fits. The average age of participants in the cohort was 60 for both men and women, and the average predicted 10-year mortality risk was 18% for women and 25% for men. Model time-integrated area under the receiver operating characteristic curve statistics demonstrated good predictive model accuracy (0.797 average), validated in the external cohort (0.756 average). Risk of mortality was impacted most by 6-minute walk distance, forced expiratory volume in 1 second and age, for both men and women.

CONCLUSIONS

Current and former smokers exhibited a wide range of mortality risk over a 10- year period. Our models can identify higher risk individuals who can be targeted for interventions to reduce risk of mortality, for participants with or without chronic obstructive pulmonary disease (COPD) using current Global initiative for obstructive Lung Disease (GOLD) criteria.

Visual Emphysema at Chest CT in GOLD Stage 0 Cigarette Smokers Predicts Disease Progression: Results from the COPDGene Study

Background The clinical significance of visually evident emphysema on CT images in individuals without spirometric evidence of chronic obstructive pulmonary disease (COPD) by current diagnostic criteria is, to the knowledge of the authors, unknown. Purpose To evaluate whether participants with visually evident emphysema at CT were more likely to have progressive disease and increased mortality at 5 years compared with those without visual emphysema. Materials and Methods This secondary analysis of the prospective Genetic Epidemiology of COPD study evaluated current or former smokers enrolled between 2008 and 2011 who did not meet current criteria for COPD (defined as Global Initiative for Obstructive Lung Disease stage 0). Statistical analysis was performed by using linear mixed models to estimate mean physiologic, imaging, and clinical outcomes for those with and without visual emphysema. Hazard ratios for mortality were calculated by using Cox regression models with emphysema as the main predictor. Results Of the 4095 participants, 48.3% (1979 participants; 1096 men and 883 women; mean age, 57 years ± 8 [standard deviation]) had trace or greater visual emphysema at CT and 51.7% (2116 participants; 1068 men and 1048 women; mean age, 56 years ± 8) had no emphysema at CT. At 5 years, participants with visual emphysema at CT demonstrated progressive airflow obstruction with lower values of ratio of forced expiratory volume in 1 second (FEV₁)-to-functional vital capacity (FVC) ratio (-1.7 vs -0.7) and greater progression in quantitative emphysema measured by 15th percentile lung density (-3.3 vs -0.3 HU), adjusted lung density (-3.1 vs -0.2 g/L), and percentage of lung voxels with CT attenuation less than -950 HU (0.17 vs -0.20) than participants without emphysema (P < .001 for each). The rate of quantitative emphysema progression increased with greater grades of emphysema severity within the emphysema group. Conclusion The presence of visual emphysema at CT in current and former Global Initiative for Obstructive Lung Disease stage 0 smokers predicted structural and physiologic disease progression. © RSNA, 2020 Online supplemental material is available for this article. See also the editorial by Grenier in this issue.

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.

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.

Carotid Artery Stiffness is Associated With Cognitive Performance in Former Smokers With and Without Chronic Obstructive Pulmonary Disease

Background

Heavy smokers perform worse on neuropsychological assessment than age‐matched peers. However, traditional pulmonary measures of airflow limitation and hypoxemia explain only a modest amount of variance in cognition. The current objective was to determine whether carotid artery stiffness is associated with cognition in former smokers beyond the effects of amount of smoking and pulmonary function.

Methods and Results

Eighty‐four former smokers including individuals across a spectrum of airflow limitation severity were included: 30 without chronic obstructive pulmonary disease (Global Initiative for Chronic Obstructive Lung Disease [GOLD] 0 with normal spirometry and lung computed tomography), 31 with mild‐moderate chronic obstructive pulmonary disease (GOLD 1–2), and 23 with severe‐very severe chronic obstructive pulmonary disease (GOLD 3–4). Participants completed questionnaires, spirometry, carotid ultrasonography, and neuropsychological testing. Multiple linear regression was used to determine whether carotid artery stiffness is associated with neuropsychological performance in 4 cognitive domains after adjusting for age, sex, pack‐years of smoking, estimated premorbid intellectual functioning, and airflow limitation. Higher carotid artery β‐stiffness index was associated with reduced executive functioning‐processing speed in the fully adjusted model (β=−0.49, SE=0.14; P=0.001). Lower premorbid intellectual function, male sex, and presence of airflow limitation (GOLD 1 or 2 and GOLD 3 or 4) were also associated with worse executive functioning‐processing speed. β‐Stiffness index was not significantly associated with performance in other cognitive domains.

Conclusions

Carotid artery stiffness is associated with worse performance on executive functioning‐processing speed in former smokers beyond the effects of aging, amount of past smoking, severity of airflow limitation, and hypoxemia. Future research should examine whether carotid stiffness can be used to identify former smokers at risk for subsequent cognitive impairment.

Primary adrenal insufficiency in the United States: diagnostic error and patient satisfaction with treatment

Background The objective of the study was to assess the diagnostic process, access to care and treatment adequacy for primary adrenal insufficiency (PAI) patients from a US-based online registry. Methods The National Adrenal Diseases Foundation (NADF) patient registry from 2015 to 2016 was used for a cross-sectional assessment of PAI patients. Five hundred and forty-one adults met the study inclusion criteria (US residents, age >20, self-reported physician diagnosis of PAI and replacement dosing for cortisol). Issues in diagnosis, comorbid conditions, symptoms, with demographic and socioeconomic characteristics were determined. Disease management assessment included medication dose, patient satisfaction with function, and education. Factors associated with adrenal crisis were noted. Results The cohort was predominantly female (83%), non-Hispanic White (97%), and well-educated (94% > high school education). A majority (57%) of patients reported difficulty with initial diagnosis, while 27% felt that their current steroid replacement was not adequate. Comorbid thyroid disease and other autoimmune conditions were common among PAI patients in the registry. More than three-quarters (78%) of patients used hydrocortisone for glucocorticoid replacement with a mean dose of 24.4 (standard deviation [SD]: 8.7) mg. Mean dose of hydrocortisone has declined over time following current treatment recommendations. Conclusions Timely, accurate diagnosis remains a problem for patients with primary adrenal insufficiency in an affluent, well-educated US cohort. Episodes of adrenal crisis are common and replacement steroid treatment is not always effective for patient function. Comprehensive information about outcomes of care for PAI in the US remains limited and the establishment of a research-specific registry to foster future research may be desirable. Patient registry data is a valuable source of information on diagnostic error and outcomes of care in rare diseases.

Omics and the Search for Blood Biomarkers in Chronic Obstructive Pulmonary Disease. Insights from COPDGene

There is an unmet need for blood biomarkers in diagnosis and prognosis of chronic obstructive pulmonary disease (COPD). The search for these biomarkers has been revolutionized by high-throughput sequencing techniques and multiplex platforms that can measure thousands of gene transcripts, proteins, or metabolites. We review COPDGene (Genetic Epidemiology of COPD) project publications that include DNA methylation, transcriptomic, proteomic, and metabolomic blood biomarkers and discuss their impact on COPD. Key contributions from COPDGene include identification of DNA methylation effects from smoking and genetic variation, new transcriptomic signatures in the blood, identification of protein biomarkers associated with severity and progression (e.g., sRAGE [soluble receptor for advanced glycosylation end products], inflammatory cytokines IL-6 and IL-8), and identification of small molecules (ceramides and sphingomyelin) that may be pathogenic. COPDGene studies have revealed that some of the COPD genome-wide association study polymorphisms are strongly associated with blood biomarkers (e.g., rs2070600 in AGER is a pQTL [protein quantitative trait locus] for sRAGE), underscoring the importance of combining omics results. Investigators have developed molecular networks identifying lower CD4⁺ resting memory cells associated with COPD. Genes, proteins, and metabolite networks are particularly important because the explanatory value of any single molecule is small (1-10%) compared with panels of multiple markers. COPDGene has been a useful resource in the identification and validation of multiple biomarkers for COPD. These biomarkers, either combined in multiple biomarker panels or integrated with other omics data types, may lead to novel diagnostic and prognostic tests for COPD phenotypes and may be relevant for assessing novel therapies.

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.

Genetic Advances in Chronic Obstructive Pulmonary Disease. Insights from COPDGene

Chronic obstructive pulmonary disease (COPD) is a common and progressive disease that is influenced by both genetic and environmental factors. For many years, knowledge of the genetic basis of COPD was limited to Mendelian syndromes, such as alpha-1 antitrypsin deficiency and cutis laxa, caused by rare genetic variants. Over the past decade, the proliferation of genome-wide association studies, the accessibility of whole-genome sequencing, and the development of novel methods for analyzing genetic variation data have led to a substantial increase in the understanding of genetic variants that play a role in COPD susceptibility and COPD-related phenotypes. COPDGene (Genetic Epidemiology of COPD), a multicenter, longitudinal study of over 10,000 current and former cigarette smokers, has been pivotal to these breakthroughs in understanding the genetic basis of COPD. To date, over 20 genetic loci have been convincingly associated with COPD affection status, with additional loci demonstrating association with COPD-related phenotypes such as emphysema, chronic bronchitis, and hypoxemia. In this review, we discuss the contributions of the COPDGene study to the discovery of these genetic associations as well as the ongoing genetic investigations of COPD subtypes, protein biomarkers, and post-genome-wide association study analysis.

Five-year Progression of Emphysema and Air Trapping at CT in Smokers with and Those without Chronic Obstructive Pulmonary Disease: Results from the COPDGene Study

Background CT is used to quantify abnormal changes in the lung parenchyma of smokers that might overlap chronic obstructive pulmonary disease (COPD), but studies on the progression of expiratory air trapping in smokers are scarce. Purpose To evaluate the relationship between longitudinal changes in forced expiratory volume in 1 second (FEV₁) and CT-quantified emphysema and air trapping in smokers. Materials and Methods Cigarette smokers with and those without COPD participating in the multicenter observational COPDGene study were evaluated. Subjects underwent inspiratory and expiratory chest CT and spirometry at baseline and 5-year follow-up. Emphysema was quantified by using adjusted lung density (ALD). Air trapping was quantified by using mean lung density at expiratory CT and CT-measured functional residual capacity-to-total lung volume ratio. Linear models were used to regress quantitative CT measurements taken 5 years apart, and models were fit with and without adding FEV₁ as a predictor. Analyses were stratified by Global Initiative for Chronic Obstructive Lung Disease (GOLD) stage (GOLD 0, no COPD; GOLD 1, mild COPD; GOLD 2, moderate COPD; GOLD 3, severe COPD; GOLD 4, very severe COPD). Subjects with preserved FEV₁-to-forced vital capacity ratio and reduced FEV₁ percentage predicted were categorized as having preserved ratio impaired spirometry (PRISm). Results A total of 4211 subjects (503 with PRISm; 2034 with GOLD 0, 388 with GOLD 1, 816 with GOLD 2, 381 with GOLD 3, 89 with GOLD 4) were evaluated. ALD decreased by 1.7 g/L (95% confidence interval [CI]: -2.5, -0.9) in subjects with GOLD 0 at baseline and by 5.3 g/L (95% CI: -6.2, -4.4) in those with GOLD 1-4 (P < .001 for both). When adjusted for changes in FEV₁, corresponding numbers were -2.2 (95% CI: -3.0, -1.3) and -4.6 g/L (95% CI: -5.6, -3.4) (P < .001 for both). Progression in air trapping was identified only in GOLD stage 2-4. Approximately 33%-50% of changes in air trapping in GOLD stages 2-4 were accounted for by changes in FEV₁. Conclusion CT measures of emphysema and air trapping increased over 5 years in smokers. Forced expiratory volume in one second accounted for less than 10% of emphysema progression and less than 50% of air trapping progression detected at CT. © RSNA, 2020 Online supplemental material is available for this article.

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.

Nonclinical Safety and Toxicokinetics of MnTE-2-PyP (BMX-010), a Topical Agent in Phase 2 Trials for Psoriasis and Atopic Dermatitis

Since our earlier publication (Gad et al, 2013), BioMimetix has advanced BMX-010 (Manganese (III) meso-tetrakis(N-ethylpyridinium-2-yl)porphyrin or MnTE020PyP; CASRN 219818-60-7) into clinical development as a topical agent for the treatment of psoriasis, atopic dermatitis, and pruritus (idiopathic nonspecific itch). A multiple dose phase I study has been completed in 64 patients without any serious adverse effects. During the course of development, the formulation was initially a gel but has been modified to a cream formulation. The nonclinical safety program has been carried onward to assess preclinical risk to patients. Additional studies completed and reported here include dermal sensitization in a Guinea Pig maximization test study, 2 rabbit phototoxicity studies, a 28-day oral toxicity study in juvenile mice, a 28-day topical systemic toxicity study in Gottingen minipigs, range-finding studies, and complete embryo-fetal developmental toxicity (Segment II) studies in mice and rabbits, an ICH M7 compliant qualification of impurities using 2 (Q)SAR in silico methods, and a 14-day subcutaneous toxicity study of mice to qualify an impurity. All studies (except the (Q)SAR evaluations) were performed in accordance with Good Laboratory Practices (GLP) using Good Manufacturing Practices (GMP) drug substance. The systemic toxicity studies, with the exception of the juvenile toxicity study, included toxicokinetic evaluations, which are reported here. The phase I clinical study had 67 patient participants who received topically applied BMX-010, and there were no notable safety findings and included pharmacokinetic determinations on these patients which are also reported here. Chronic GLP toxicity studies have been initiated in the mouse (6-month oral) and minipig (9-month dermal). To date, the only observed nonclinical toxicity remains a reversible hypertension seen in mice in response to C_max levels with a no effect threshold, and there have been no drug-related adverse effects.