The chronic bronchitis phenotype in chronic obstructive pulmonary disease: features and implications

Association of bronchial disease on CT imaging and clinical definitions of chronic bronchitis in a single-center COPD phenotyping study

INTRODUCTION

Chronic Bronchitis (CB) represents a phenotype of chronic obstructive pulmonary disease (COPD). While several definitions have been used for diagnosis, the relationship between clinical definitions and radiologic assessment of bronchial disease (BD) has not been well studied. The aim of this study was to evaluate the relationship between three clinical definitions of CB and radiographic findings of BD in spirometry-defined COPD patients.

METHODS

A cross-sectional analysis was performed from a COPD phenotyping study. It was a prospective observational cohort. Participants had spirometry-defined COPD and available chest CT imaging. Comparison between CB definitions, Medical Research Council (CBMRC), St. George's Respiratory Questionnaire (CBSGRQ), COPD Assessment Test (CBCAT) and CT findings were performed using Cohen's Kappa, univariate and multivariate logistic regressions.

RESULTS

Of 112 participants, 83 met inclusion criteria. Demographics included age of 70.1 ± 7.0 years old, predominantly male (59.0 %), 45.8 ± 30.8 pack-year history, 21.7 % actively smoking, and mean FEV1 61.5 ± 21.1 %. With MRC, SGRQ and CAT definitions, 22.9 %, 36.6 % and 28.0 % had CB, respectively. BD was more often present in CB compared to non-CB patients; however, it did not have a statistically significant relationship between any of the CB definitions. CBSGRQ had better agreement with radiographically assessed BD compared to the other two definitions.

CONCLUSION

Identification of BD on CT was associated with the diagnoses of CB. However, agreement between imaging and definitions were not significant, suggesting radiologic findings of BD and criteria defining CB may not identify the same COPD phenotype. Research to standardize imaging and clinical methods is needed for more objective identification of COPD phenotypes.

Clinical significance of chronic bronchitis in different racial groups

BACKGROUNDS

Limited data are available on racial differences in the clinical features of chronic bronchitis (CB) patients with chronic obstructive pulmonary disease (COPD). In this study, we aimed to compare clinical features among CB patients of different races. We also analyzed the clinical significance of CB, defined classically and based on the COPD Assessment Test (CAT), to validate the CAT-based definition.

METHODS

We analyzed patient data extracted from the Korean COPD Subgroup Study (KOCOSS) cohort (2012-2021) and US Genetic Epidemiology of COPD (COPDGene) study (2008-2011). We compared clinical characteristics among CB and non-CB patients of three different races using two CB definitions.

RESULTS

In this study, 3,462 patients were non-Hispanic white (NHW), 1,018 were African American (AA), and 1,793 were Asian. The proportions of NHW, AA, and Asian patients with CB according to the classic definition were 27.4%, 20.9%, and 10.7%, compared with 25.2%, 30.9%, and 23.0% according to the CAT-based definition, respectively. The risk of CB prevalence was highest in NHW and lowest in Asian COPD patients. Among all races, CB patients were more likely to be current smokers, have worse respiratory symptoms and poorer health-related quality of life (HrQoL), and to have decreased lung function and exercise capacity. Most of these characteristics showed similar associations with the outcomes between the two definitions of CB. A binominal regression model revealed that CB patients of all races had an increased risk of future exacerbations according to both CB definitions, except for Asian patients with classically defined CB.

CONCLUSIONS

The presence of CB was associated with worse respiratory symptoms, HrQoL, exercise capacity and lung function, and more exacerbations, regardless of race or CB definition. The CAT-based definition may be more useful for assessing the risk of future exacerbations in Asian COPD patients.

Potential systemic effects of acquired CFTR dysfunction in COPD

Chronic obstructive pulmonary disease (COPD) is characterized by airflow limitation, respiratory symptoms, inflammation of the airways, and systemic manifestations of the disease. Genetic susceptibility and environmental factors are important in the development of the disease, particularly exposure to cigarette smoke which is the most notable risk factor. Mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene are the cause of cystic fibrosis (CF), which shares several pathophysiological pulmonary features with COPD, including airway obstruction, chronic airway inflammation and bacterial colonization; in addition, both diseases also present systemic defects leading to comorbidities such as pancreatic, gastrointestinal, and bone-related diseases. In patients with COPD, systemic CFTR dysfunction can be acquired by cigarette smoking, inflammation, and infection. This dysfunction is, on average, about half of that found in CF. Herein we review the literature focusing on acquired CFTR dysfunction and the potential role in the pathogenesis of comorbidities associated with COPD and chronic bronchitis.

Bronchoscopic interventions for chronic bronchitis

PURPOSE OF REVIEW

Chronic bronchitis is a phenotype of chronic obstructive pulmonary disease (COPD), characterized by chronic cough and sputum production, associated with an increased rate of COPD exacerbations and hospital admissions, a more rapid decline in lung function and reduced life expectancy. Despite optimal medical therapy, chronic bronchitis remains difficult to treat. Interventional bronchoscopic procedures offer novel therapeutic approaches to this highly symptomatic condition.

RECENT FINDINGS

A characteristic feature of chronic bronchitis is the presence of an abnormal epithelium with excessive mucus producing cells, parasympathetic overactivity, and airway inflammation. Metered cryospray and bronchial rheoplasty are designed to target this abnormal epithelium to reduce mucus production and inflammation. Targeted lung denervation aims to reduce parasympathetic overactivity, which may drive mucus hypersecretion. Here, we review the available evidence to determine the safety and efficacy across the bronchoscopic interventions.

SUMMARY

Interventional bronchoscopy is a rapidly expanding field and its application in the treatment of chronic bronchitis has been recognized by the Global initiative for chronic Obstructive Lung Disease (GOLD). The outcomes from the latest clinical trials will guide future treatment approaches in patients with difficult to treat chronic bronchitis.

Re-evaluation for systematic reviews of traditional Chinese medicine in the treatment of chronic bronchitis

BACKGROUND

Chronic bronchitis (CB) is a common clinical chronic respiratory disease, which has a high incidence in the middle aged and elderly population. With the development of the disease, the number of acute attacks becomes more and more frequent, which leads to the continuous decrease of lung function. If not treated in time, it will lead to a variety of complications and seriously affect the quality of life of patients. Traditional Chinese medicine (TCM) or TCM combined with western medicine is highly effective in the treatment of CB disease. In recent years, there are many systematic reviews on the use of TCM therapy in the treatment of CB, and the efficacy and safety of TCM in the treatment of CB diseases are evaluated. The aim of this study was to re-evaluate the Meta analysis/Systematic reviews (MAs/SRs) of TCM for the treatment of CB, aiming to provide a clinical basis for the treatment of CB by TCM.

METHODS

Retrieval among Chinese and English databases such as China National Knowledge Infrastructure, Wanfang database, China Scientific Journals Database, SinoMed, PubMed, Web of Science, The Cochrane Library and EMbase, etc. were conducted within the duration from database establish Tion date to March 2023.The included research was independently conducted by 2 researchers for literature screening, data extraction, and quality evaluation. The AMSTAR 2 scale was used to evaluate the quality of the report, the PRISMA 2020 statement evaluated the quality of the report, the ROBIS tool evaluated the risk of bias, and the GRADE quality evaluation tool evaluated the quality of the evidence.

RESULTS

Fifteen MAs/SRs were included, for a total of 224 studies involving 20,710 patients with CB. The 15 studies included in AMSTAR 2 are of very low quality. The ROBIS evaluation results showed that 8 MAs/SRs were considered to have high risk and 7 with low risk. The PRISMA 2020 report quality showed evaluation results of the included studies scores between 24 and 30, among them 13 with high quality and 2 with low quality. The GRADE system results showed that, within 70 outcome indicators, only 14 of them have moderate quality for evidence, with 31 for low quality, 25 for very low quality, and none for high quality.

CONCLUSION

The MAs/SRs methodological quality of using TCM for treatment CB is generally poor, the quality of reports as well as evidence are generally low, and the risk of bias is high, therefore we should treat these results with caution.

Airway Mucosal Remodeling: Mechanism of Action and Preclinical Data of Pulsed Electric Fields for Chronic Bronchitis and Mucus Hypersecretion

Patients living with chronic bronchitis (CB) suffer from physical limitations and poor quality of life. In general, treatment options that directly address the mucus hypersecretion component of CB are quite limited. Chronic airway inflammation and the associated hypersecretion and cough that are pathognomonic for CB generally result from long-term exposure to airway irritants such as tobacco use and other environmental insults. This, in turn, results in an increase in the quantity and change in composition of the airway mucosa as a consequence of altered goblet cells, club cells, and submucosal glands. Pulsed electric fields (PEFs) provide a method for eradicating the cellular constituents of tissue with limited impact on the stromal proteins. Preclinical evidence in porcine airways demonstrated that particular PEF waveforms allowed for salutary remodeling of the epithelial and submucosal airway tissue layers and appeared to foster rapid regeneration and recovery of the tissue. Therefore, a therapeutic opportunity might exist whereby the application of a specific form of PEF may result in a reduction of the cellular secretory constituents of the airway while also reducing airway mucosal inflammation. This review discusses the use of such PEF to address the underlying disease processes in CB including challenges around device design, dosing, and appropriate delivery methods. Further, we outline considerations for the transition to human airways along with a brief examination of the initial work treating CB patients, suggesting that the therapy is well tolerated with limited adverse events.

Development of an Electronic Health Record-Based Algorithm for Predicting Lung Cancer Screening Eligibility in the Population-Based Research to Optimize the Screening Process Lung Research Consortium

PURPOSE

Lung cancer screening (LCS) guidelines in the United States recommend LCS for those age 50-80 years with at least 20 pack-years smoking history who currently smoke or quit within the last 15 years. We tested the performance of simple smoking-related criteria derived from electronic health record (EHR) data and developed and tested the performance of a multivariable model in predicting LCS eligibility.

METHODS

Analyses were completed within the Population-based Research to Optimize the Screening Process Lung Consortium (PROSPR-Lung). In our primary validity analyses, the reference standard LCS eligibility was based on self-reported smoking data collected via survey. Within one PROSPR-Lung health system, we used a training data set and penalized multivariable logistic regression using the Least Absolute Shrinkage and Selection Operator to select EHR-based variables into the prediction model including demographics, smoking history, diagnoses, and prescription medications. A separate test data set assessed model performance. We also conducted external validation analysis in a separate health system and reported AUC, sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy metrics associated with the Youden Index.

RESULTS

There were 14,214 individuals with survey data to assess LCS eligibility in primary analyses. The overall performance for assigning LCS eligibility status as measured by the AUC values at the two health systems was 0.940 and 0.938. At the Youden Index cutoff value, performance metrics were as follows: accuracy, 0.855 and 0.895; sensitivity, 0.886 and 0.920; specificity, 0.896 and 0.850; PPV, 0.357 and 0.444; and NPV, 0.988 and 0.992.

CONCLUSION

Our results suggest that health systems can use an EHR-derived multivariable prediction model to aid in the identification of those who may be eligible for LCS.

The Lung Microbiome in COPD and Lung Cancer: Exploring the Potential of Metal-Based Drugs

Chronic obstructive pulmonary disease (COPD) and lung cancer 17 are two of the most prevalent and debilitating respiratory diseases worldwide, both associated with high morbidity and mortality rates. As major global health concerns, they impose a substantial burden on patients, healthcare systems, and society at large. Despite their distinct aetiologies, lung cancer and COPD share common risk factors, clinical features, and pathological pathways, which have spurred increasing research interest in their co-occurrence. One area of particular interest is the role of the lung microbiome in the development and progression of these diseases, including the transition from COPD to lung cancer. Exploring novel therapeutic strategies, such as metal-based drugs, offers a potential avenue for targeting the microbiome in these diseases to improve patient outcomes. This review aims to provide an overview of the current understanding of the lung microbiome, with a particular emphasis on COPD and lung cancer, and to discuss the potential of metal-based drugs as a therapeutic strategy for these conditions, specifically concerning targeting the microbiome.

Explore bioactive ingredients and potential mechanism of Houpo Mahuang decoction for chronic bronchitis based on UHPLC-Q exactive orbitrap HRMS, network pharmacology, and experiment verification

ETHNOPHARMACOLOGICAL RELEVANCE

Chronic bronchitis (CB) affects a growing number of people and may be linked to lung function impairment. The traditional Chinese medicine formula Houpo Mahuang Decoction (HPMHD) has been used for clinical treatment of respiratory diseases for thousands of years. Until now, its bioactive ingredients, potential targets and molecular mechanism remain unclear.

AIM OF THE STUDY

To investigate the effect of HPMHD on the treatment of CB and explore the bioactive ingredients and possible mechanisms of HPMHD against CB.

MATERIALS AND METHODS

UHPLC-Q Exactive Orbitrap HRMS was performed to analyze the chemical components of HPMHD. The mechanism of multiple components, targets and pathways of HPMHD in the treatment of chronic bronchitis were explored by network pharmacology. Additionally, CB mice model induced by lipopolysaccharide (LPS) and smoking was used to evaluate the anti-chronic bronchitis activity of HPMHD in vivo. Pulmonary pathology was determined by hematoxylin and eosin (H&E) measurement. The levels of TNF-α and IL-6 in lung were measured by ELISA. The immunofluorescence experiments were carried out for the expression of IL-1β, TNF-α, IL-6 and NF-κB p-P65/P65 in lung. Western blot assays were performed to quantify and visualize the protein expression of NF-κB p-P65/P65 in mice lung.

RESULTS

Data showed that 79 compounds were identified in HPMHD. The network pharmacology results showed 53 compounds were hinted their effectivity for the treatment of chronic bronchitis with HPMHD, such as ephedrine, schisantherin A, and honokiol. The main targets were predicted as 37 genes, including TNF, TP53, IL6 and so on. HPMHD ameliorated lung damages in mice and inhibited the NF-κB signaling pathway, one of the pathways plotted by KEGG pathway enrichment analysis, by reducing IL-1β, TNF-α and IL-6 expression and significantly downregulating the NF-κB p-P65/P65.

CONCLUSION

In summary, the complex chemical components of HPHMD was successfully elucidate by UHPLC-Q Exactive Orbitrap HRMS. The study based on network pharmacology and experiment verification indicated that HPMHD can decreased inflammatory response in lung to treat CB. The underlying mechanism may be related to the reduction of inflammation by down-regulated the NF-κB pathways.

Effect of chronic mucus hypersecretion on treatment responses to inhaled therapies in patients with chronic obstructive pulmonary disease: Post hoc analysis of the IMPACT trial

BACKGROUND AND OBJECTIVE

Chronic mucus hypersecretion (CMH) is a clinical phenotype of COPD. This exploratory post hoc analysis assessed relationship between CMH status and treatment response in IMPACT.

METHODS

Patients were randomized to once-daily fluticasone furoate/umeclidinium/vilanterol (FF/UMEC/VI) 100/62.5/25 μg, FF/VI 100/25 μg or UMEC/VI 62.5/25 μg and designated CMH+ if they scored 1/2 in St George's Respiratory Questionnaire (SGRQ) questions 1 and 2. Endpoints assessed by baseline CMH status included on-treatment exacerbation rates, change from baseline in trough forced expiratory volume in 1 second, SGRQ total score, COPD Assessment Test (CAT) score, proportion of SGRQ and CAT responders at Week 52 and safety.

RESULTS

Of 10,355 patients in the intent-to-treat population, 10,250 reported baseline SGRQ data (CMH+: 62% [n = 6383]). FF/UMEC/VI significantly (p < 0.001) reduced on-treatment moderate/severe exacerbation rates versus FF/VI and UMEC/VI in CMH+ (rate ratio: 0.87 and 0.72) and CMH- patients (0.82 and 0.80). FF/UMEC/VI significantly (p < 0.05) reduced on-treatment severe exacerbation rates versus UMEC/VI in CMH+ (0.62) and CMH- (0.74) subgroups. Similar improvements in health status and lung function with FF/UMEC/VI were observed, regardless of CMH status. In CMH+ patients, FF/VI significantly (p < 0.001) reduced on-treatment moderate/severe and severe exacerbation rates versus UMEC/VI (0.83 and 0.70).

CONCLUSION

FF/UMEC/VI had a favourable benefit: risk profile versus dual therapies irrespective of CMH status. The presence of CMH did not influence treatment response or exacerbations, lung function and/or health status. However, CMH did generate differences when dual therapies were compared and the impact of CMH should be considered in future trial design.

Urinary metals, arsenic, and polycyclic aromatic hydrocarbon exposure and risk of chronic bronchitis in the US adult population

Metals, arsenic, and polycyclic aromatic hydrocarbons (PAHs) have all been linked to respiratory diseases. Chronic bronchitis, which is a form of chronic obstructive pulmonary disease (COPD), is a major public health concern and source of morbidity and mortality in the US. The purpose of this study was to analyze the correlation of 14 urinary metals (antimony, barium, cadmium, cesium, cobalt, lead, manganese, mercury, molybdenum, strontium, thallium, tin, tungsten, uranium), seven species of arsenic, and seven forms of polycyclic aromatic hydrocarbon (PAH) concentrations and chronic bronchitis in the US population. A cross-sectional analysis using three datasets from the National Health and Nutrition Examination Survey (NHANES) between 2011 and 2016 in adults, aged 20 years and older. Chronic bronchitis was determined using a self-questionnaire from the NHANES dataset. A specialized weighted complex survey design analysis package was used to analyze NHANES data. Multivariate logistic regression models were used to determine the correlation between urinary metals, arsenic, PAHs, and chronic bronchitis. Models were adjusted for lifestyle and demographic factors. A total of 4186 participants were analyzed; 49.8% were female and 40.5% were non-Hispanic White. All seven types of PAHs showed a positive association with chronic bronchitis (1-hydroxynaphthalene odds ratio (OR): 1.559, 95% confidence interval (CI): 1.271-1.912; 2-hydroxynaphthalene OR: 2.498, 95% CI: 1.524-4.095; 3-hydroxyfluorene OR: 2.752, 95% CI: 2.100-3.608; 2-hydroxyfluorene OR: 3.461, 95% CI: 2.438-4.914; 1-hydroxyphenanthrene OR: 2.442, 95% CI: 1.515-3.937; 1-hydroxypyrene OR: 2.828, 95% CI: 1.728-4.629; 2 & 3-hydroxyphenanthrene OR: 3.690, 95% CI: 2.309-5.896). Of the metals, only urinary cadmium showed a statistically significant positive association (OR: 2.435, 95% CI: 1.401-4.235) with chronic bronchitis. No other metals or arsenic were correlated with chronic bronchitis. Seven forms of urinary PAHs, cadmium, and several demographic factors were associated with chronic bronchitis.

Lung Cancer in the Course of COPD-Emerging Problems Today

Tobacco smoking remains the main cause of tobacco-dependent diseases like lung cancer, chronic obstructive pulmonary disease (COPD), in addition to cardiovascular diseases and other cancers. Whilst the majority of smokers will not develop either COPD or lung cancer, they are closely related diseases, occurring as co-morbidities at a higher rate than if they were independently triggered by smoking. A patient with COPD has a four- to six-fold greater risk of developing lung cancer independent of smoking exposure, when compared to matched smokers with normal lung function. The 10 year risk is about 8.8% in the COPD group and only 2% in patients with normal lung function. COPD is not a uniform disorder: there are different phenotypes. One of them is manifested by the prevalence of emphysema and this is complicated by malignant processes most often. Here, we present and discuss the clinical problems of COPD in patients with lung cancer and against lung cancer in the course of COPD. There are common pathological pathways in both diseases. These are inflammation with participation of macrophages and neutrophils and proteases. It is known that anticancer immune regulation is distorted towards immunosuppression, while in COPD the elements of autoimmunity are described. Cytotoxic T cells, lymphocytes B and regulatory T cells with the important role of check point molecules are involved in both processes. A growing number of lung cancer patients are treated with immune check point inhibitors (ICIs), and it was found that COPD patients may have benefits from this treatment. Altogether, the data point to the necessity for deeper analysis and intensive research studies to limit the burden of these serious diseases by prevention and by elaboration of specific therapeutic options.

Association of Nonobstructive Chronic Bronchitis With All-Cause Mortality: A Systematic Literature Review and Meta-analysis

BACKGROUND

The effect of nonobstructive chronic bronchitis (CB) on mortality is unclear.

RESEARCH QUESTION

Is nonobstructive CB associated with increased all-cause mortality?

STUDY DESIGN AND METHODS

We conducted a systematic literature review and meta-analysis to assess the association of nonobstructive CB and all-cause mortality. We searched for articles that included both CB and mortality in the title, abstract, or both in PubMed and EMBASE. We excluded studies in which participants demonstrated obstructive spirometry findings and studies in which CB and mortality were not defined. We used the Newcastle-Ottawa Quality Assessment Scale to assess study quality. We pooled adjusted hazard ratios (HRs) using the random effects model and inverse variance weighting. We conducted stratified analysis by the definition of CB and smoking status. We used Cochran's Q and I² to assess for heterogeneity. We assessed publication bias by visual inspection of a funnel plot.

RESULTS

Of 5,014 titles identified, eight fulfilled the inclusion and exclusion criteria. Overall nonobstructive CB was associated with all-cause mortality (HR, 1.37; 95% CI, 1.26-1.50) with no statistically significant heterogeneity (P = .14; I² = 29%). Nonobstructive CB was associated with increased mortality in studies that defined CB as any respiratory symptoms (broad definition; HR, 1.28; 95% CI, 1.10-1.48; I² = 0%) as well as in the rest of the studies (HR, 1.40; 95% CI, 1.26-1.56; I² = 37%). Nonobstructive CB was associated with increased mortality in ever smokers (HR, 1.49; 95% CI, 1.35-1.64; I² = 0%), but was not associated with increased mortality in never smokers (HR, 1.22; 95% CI, 0.90-1.66), and moderate heterogeneity was found (P = .10; I² = 49%). The funnel plot did not indicate evidence of a publication bias because it showed symmetrical distribution of studies.

INTERPRETATION

Nonobstructive CB is associated with increased all-cause mortality, and this association seems to be present only in current and former smokers. Further research should investigate whether this high-risk population may benefit from early therapeutic intervention.

TRIAL REGISTRY

PROSPERO; No.: CRD42021253596; URL: www.crd.york.ac.uk/prospero.

Association Between Vitamin D Level and Respiratory Symptoms in Patients with Stable Chronic Obstructive Pulmonary Disease

Purpose

Vitamin D insufficiency or deficiency is prevalent in patients with chronic obstructive pulmonary disease (COPD). However, the association between vitamin D levels and respiratory symptoms in patients with stable COPD has not been fully investigated. This study evaluated the association between vitamin D levels and respiratory symptoms in patients with stable COPD.

Patients and Methods

Patients with COPD who had their serum 25-hydroxyvitamin D (25-OH vitamin D) level measured within 6 months of spirometry between January 2016 and April 2020 were retrospectively included. Respiratory symptoms were assessed using the modified Medical Research Council (mMRC) scale and COPD assessment test (CAT) score.

Results

Of the 329 included patients, 193, 88, and 48 were categorized as having vitamin D deficiency (<20 ng/mL), insufficiency (20–29 ng/mL), and sufficiency (≥30 ng/mL), respectively. The mean serum 25-OH vitamin D level of each group was 13.45 ng/mL, 24.61 ng/mL, and 38.90 ng/mL, respectively. Patients with vitamin D insufficiency/deficiency showed higher CAT scores than those with vitamin D sufficiency (p = 0.004). In multivariable adjusted models, vitamin D insufficiency/deficiency was significantly associated with a CAT score of 10 or more (adjusted odds ratio [aOR] = 2.41, 95% confidence interval [CI] = 1.20–4.82, p = 0.013) and mMRC ≥ 2 (aOR = 2.39, 95% CI = 1.08–5.32, p = 0.032). Among CAT items, the amount of phlegm (p = 0.008), chest tightness (p = 0.030), breathlessness walking upstairs (p < 0.001), home activity limitations (p = 0.002), and lack of energy (p = 0.003) were significantly associated with vitamin D insufficiency/deficiency after adjustment for age, sex, body mass index, smoking history, Charlson comorbidity index, post-bronchodilator forced expiratory volume in 1 second, and season of blood draw.

Conclusion

Vitamin D insufficiency/deficiency were associated with worse respiratory symptoms in patients with stable COPD.

Comparison of clinical characteristics between chronic bronchitis and non-chronic bronchitis in patients with chronic obstructive pulmonary disease

Background

Chronic bronchitis (CB) is associated with poor outcomes in patients with chronic obstructive pulmonary disease. The aim of this study was to identify the characteristics that distinguish chronic bronchitis (CB) from non-CB. In addition, the features of mild CB versus severe CB were compared and a cut-off level was defined according to CAT1 and CAT2 scores.

Methods

This study was based on the Korea COPD Subgroup Study (KOCOSS) database, constructed in a multicenter COPD cohort study that recruited patients from 54 centers. CB was defined as CAT1 and CAT2 scores ≥ 3; severe CB was defined as CAT1 and CAT2 scores ≥ 4, while mild CB was defined as either a CAT1 or a CAT2 score < 4. Baseline characteristics, 1-year exacerbation rate, and 3-year FEV₁ decline were compared in non-CB versus CB patients and in patients with mild CB versus severe CB.

Results

Among the 2162 patients enrolled in this study, 497 (23%) had CB. These patients were more likely than non-CB patients to be current smokers; they also had higher symptom and depression/anxiety scores. Lung function tests showed lower FEV₁, FEV₁/FVC, and DLco values in CB patients. Among CB patients, 67.6% had mild disease. Symptom and depression/anxiety scores were worse in patients with severe CB than in patients with mild CB. There were no significant differences in the lung function tests of the two groups. Analysis of 1-year exacerbation rates in CB patients and non-CB patients revealed that patients with CB more frequently had moderate-to-severe exacerbations (OR = 1.46, p < 0.01). More severe exacerbation was also present in patients with severe CB than in patients with mild CB (OR = 2.52, p = 0.01). The difference in annual FEV₁ decline rate did not significantly differ either between CB patients and non-CB patients or between patients with severe CB and patients with mild CB.

Conclusions

CB patients had worse symptoms and lung function than non-CB patients; CB patients also had more frequent moderate-to-severe exacerbation. Patients with severe CB had higher symptom scores and more frequent severe exacerbation than did patients with mild CB.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12890-022-01854-x.

Fibrinogen: A Feasible Biomarker in Identifying the Severity and Acute Exacerbation of Chronic Obstructive Pulmonary Disease

Background Chronic obstructive pulmonary disease (COPD) is no longer considered a disease exclusive to the respiratory system. It is a multipronged disease with both lung and systemic involvement. Although the forced expiratory volume (FEV) in one second is one of the most commonly used markers to assess disease severity, in recent years, biomarkers such as interleukin-1 beta, serum C-X-C motif chemokine ligand 10, fibrinogen, soluble receptor for advanced glycation, surfactant protein D, and club cell secretory protein have been proven to be effective markers to assess disease severity. Objective The current study aimed to test the association of fibrinogen levels with increased exacerbation of COPD per year and lower lung function and to discuss its potential utility as a biomarker. Methodology A total of 105 participants were enrolled in the study. The study participants included 35 stable COPD patients, 35 COPD patients with acute exacerbation, and 35 non-COPD healthy controls (matched for age and gender). All patients above 18 years of age who were diagnosed with COPD as per the Global Initiative for Chronic Obstructive Disease (GOLD) guidelines were considered for inclusion in the study. The patients were divided into stable COPD group and acute exacerbations of COPD (AECOPD) group based on the Anthonisen criteria. Sociodemographic factors, six-minute walk test, Medical Research Council Dyspnea Scale, and COPD Assessment Test scale were computed. Spirometry according to the American Thoracic Society guidelines and hematological investigations including serum fibrinogen were performed. Additionally, GOLD staging and severity indices were used to determine the clinical phenotyping of COPD, namely, ADO (age, dyspnea, airflow obstruction) index, BODE (body mass index, airflow obstruction, dyspnea, and exercise capacity) index, and DOSE (dyspnea, obstruction, smoking, exacerbation) index. Results Plasma fibrinogen level was significantly higher in the COPD groups compared to the control group. Plasma fibrinogen level was elevated in AECOPD compared to stable COPD patients. In addition, fibrinogen levels showed a positive correlation with important functional indices and prognostic markers such as BODE, ADO, and DOSE indices and a negative correlation with lung function. The odds of predicting an acute exacerbation of COPD for patients with FEV of <50% and FEV of >50% were 17.2 (area under the curve [AUC] = 0.825; sensitivity = 90.4%; specificity = 62.79%) and 15.1 (AUC = 0.791; sensitivity = 57.7%; specificity = 92.5%), respectively. Conclusions Plasma fibrinogen has the potential to be an important biomarker in the management of COPD and its exacerbation due to its ability to be responsive to the COPD disease statuses such as the severity of COPD and AECOPD.

Unknown/enigmatic functions of extracellular ASC

Apoptosis-associated speck-like protein containing a caspase recruit domain (ASC), encoded by PYCARD gene, is a 22 kDa small molecule, which aggregates into ASC specks during inflammasome activation. ASC protein is an adaptor protein present in several inflammasome complexes that performs several intra- and extracellular functions, in monomeric form or as ASC specks, during physiological and pathological processes related to inflammation and adaptive immunity. Extracellular ASC specks (eASC specks) released during cell death by pyroptosis can contribute as a danger signal to the propagation of inflammation via phagocytosis and activation of surrounding cells. ASC specks are found in the circulation of patients with chronic inflammatory diseases and have been considered as relevant blood biomarkers of inflammation. eASC amplifies the inflammatory signal, may induce the production of autoantibodies, transports molecules that bind to this complex, contributing to the generation of antibodies, and can induce the maturation of cytokines promoting the modelling of the adaptive immunity. Although several advances have been registered in the last 21 years, there are numerous unknown or enigmatic gaps in the understanding of the role of eASC specks in the organism. Here, we provide an overview about the ASC protein focusing on the probable roles of eASC specks in several diseases, up to the most recent studies concerning COVID-19.

IL-36 Cytokines Promote Inflammation in the Lungs of Long-Term Smokers

Chronic obstructive pulmonary disease (COPD) is a progressive inflammatory lung disease with high morbidity and mortality. The IL-36 family are proinflammatory cytokines that are known to shape innate immune responses, including those critical to bacterial pneumonia. The objective of this study was to determine whether IL-36 cytokines promote a proinflammatory milieu in the lungs of long-term smokers with and without COPD. Concentrations of IL-36 cytokines were measured in plasma and BAL fluid from subjects in a pilot study (n = 23) of long-term smokers with and without COPD in vivo and from a variety of lung cells (from 3-5 donors) stimulated with bacteria or cigarette smoke components in vitro. Pulmonary macrophages were stimulated with IL-36 cytokines in vitro, and chemokine and cytokine production was assessed. IL-36α and IL-36γ are produced to varying degrees in murine and human lung cells in response to bacterial stimuli and cigarette smoke components in vitro. Moreover, whereas IL-36γ production is upregulated early after cigarette smoke stimulation and wanes over time, IL-36α production requires a longer duration of exposure. IL-36α and IL-36γ are enhanced systemically and locally in long-term smokers with and without COPD, and local IL-36α concentrations display a positive correlation with declining ventilatory lung function and increasing proinflammatory cytokine concentrations. In vitro, IL-36α and IL-36γ induce proinflammatory chemokines and cytokines in a concentration-dependent fashion that requires IL-36R and MyD88. IL-36 cytokine production is altered in long-term smokers with and without COPD and contributes to shaping a proinflammatory milieu in the lungs.

Is the Symptom of Cough in Chronic Obstructive Pulmonary Disease Important?

Chronic obstructive pulmonary disease (COPD) is a common disease and a significant burden worldwide. The clinical symptoms of this disease include progressive dyspnea, cough, expectoration, and wheezing, among others. At present, the primary focus has been on reducing the frequency of acute exacerbations and improving lung function and dyspnea symptoms, and limited attention has been paid to cough and expectoration symptoms, which may be associated with a decrease in lung function, more acute exacerbations, and hospitalizations. Therefore, this outcomes in patients with COPD.

Use of mucolytics in COPD: A Delphi consensus study

BACKGROUND

International guidelines recommend mucolytic agents as add-on therapy in selected patients with COPD because they may reduce exacerbations and improve health status. As the evidence varies among mucolytic agents, we used the Delphi method to assess consensus amongst an international panel of COPD experts on mucolytics use in COPD.

METHODS

53 COPD experts from 12 countries were asked to complete an online questionnaire and rate their agreement with 15 statements using a 5-point scale. The mucolytic agents evaluated were carbocysteine, erdosteine and N-acetylcysteine (NAC). Data were collected anonymously and consensus presented using descriptive statistics.

RESULTS

The 47 respondents reached consensus on the statements. They agreed that regular treatment with mucolytic agents effectively reduces the frequency of exacerbations, reduces the duration of mild-to-moderate exacerbations, and can increase the time to first exacerbation and symptom-free time in COPD patients. Consensus was consistently highest for erdosteine. The experts agreed that all three mucolytics display antioxidant and anti-inflammatory activity. Erdosteine and NAC were thought to improve the efficacy of some classes of antibacterial drugs. All three mucolytics were considered effective for the short-term treatment of symptoms of acute exacerbations when added to other drugs. The panel agreed that approved doses of mucolytic agents have favorable side-effect profiles and can be recommended for regular use in patients with a bronchitic phenotype.

CONCLUSIONS

Consensus findings support the wider use of mucolytic agents as add-on therapy for COPD. However, the differences in pharmacological actions and clinical effectiveness must be considered when deciding which mucolytic to use.

Current smoking with or without chronic bronchitis is independently associated with goblet cell hyperplasia in healthy smokers and COPD subjects

COPD, chronic bronchitis (CB) and active smoking have all been associated with goblet cell hyperplasia (GCH) in small studies. Active smoking is strongly associated with CB, but there is a disconnect between CB clinical symptoms and pathology. Chronic cough and sputum production poorly correlate with the presence of GCH or COPD. We hypothesized that the primary determinant of GCH in ever smokers with or without airflow obstruction is active smoking. Goblet Cell Density (GCD) was measured in 71 current or former smokers [32 subjects without COPD and 39 COPD subjects]. Endobronchial mucosal biopsies were stained with Periodic Acid Schiff-Alcian Blue, and GCD was measured as number of goblet cells/mm basement membrane. GCD was divided into tertiles based on log₁₀ transformed values. Log₁₀GCD was greater in current smokers compared to former smokers. Those with classically defined CB or SGRQ defined CB had a greater log₁₀ GCD compared to those without CB. Current smoking was independently associated with tertile 3 (high log₁₀GCD) whereas CB was not in multivariable regression when adjusting for lung function and demographics. These results suggest that GCH is induced by active smoke exposure and does not necessarily correlate with the clinical symptoms of CB.

A Brief History of Bronchitis in England and Wales

Chronic bronchitis is associated with hypertrophy of airway submucosal glands and with mucus and squamous metaplasia of the surface epithelium. A historical review of research on these and other pathological changes is provided. Next, from annual reports of the Registrar-General's Office (and later the Office of National Statistics), death rates per unit population from acute and chronic bronchitis (a term that here includes chronic obstructive pulmonary disease [COPD]) are calculated for England and Wales from 1838 to the present. It is argued that a large increase in the death rate between 1838 and 1879, from all forms of bronchitis combined, was due primarily to increased levels of atmospheric coal smoke, whereas a decrease from 1879 to 1935 was due to progressively cleaner air. Between 1935 and the mid-1960s, mortality from chronic bronchitis among men increased dramatically, after which it has fallen, a pattern that parallels changes in cigarette smoking. Finally, a brief historical review of the treatments for chronic bronchitis is presented.

Respiratory symptoms and chronic bronchitis in people with and without HIV infection

OBJECTIVES

High rates of respiratory symptoms and chronic bronchitis (CB) are reported in people with HIV infection (PWH). We investigated the prevalence of respiratory symptoms and CB in PWH and HIV-negative people in the Pharmacokinetic and clinical Observations in PeoPle over fiftY (POPPY) study.

METHODS

Assessment of respiratory symptoms and CB was undertaken using the modified form of the St. George's Respiratory Questionnaire for chronic obstructive pulmonary disease (COPD). Univariate (χ² tests, Mann-Whitney U tests and Spearman's rank correlation) and multivariable (linear and logistic regression) analyses were performed to consider associations of respiratory symptoms with demographic, lifestyle and HIV-related parameters, and with depressive symptoms and quality of life.

RESULTS

Among the 619 participants, respiratory Symptom scores were higher in older and younger PWH compared to older HIV-negative people, with median (interquartile range) scores of 17.7 (6.2, 39.5), 17.5 (0.9, 30.0) and 9.0 (0.9, 17.5), respectively (P = 0.0001); these differences remained significant after confounder adjustment. Sixty-three participants (10.2%) met the criteria for CB [44 (14.0%) older PWH, 14 (9.2%) younger PWH, and five (3.3%) older HIV-negative people; P = 0.002], with these differences also remaining after adjustment for confounding variables, particularly smoking status [older vs. younger PWH: odds ratio (OR) 4.48 (95% confidence interval (CI) 1.64, 12.30); P = 0.004; older PWH vs. HIV-negative people: OR 4.53 (95% CI 1.12, 18.28); P = 0.03]. Respiratory symptoms and CB were both associated with greater depressive symptom scores and poorer quality of life. No strong associations were reported between CB and immune function, HIV RNA or previous diagnosis of any AIDS event.

CONCLUSIONS

Respiratory symptoms and CB are more common in PWH than in demographically and lifestyle-similar HIV-negative people and are associated with poorer mental health and quality of life.

Haemophilus influenzae persists in biofilm communities in a smoke-exposed ferret model of COPD

Rationale

Non-typeable Haemophilus influenzae (NTHi) is a common inhabitant of the human nasopharynx and upper airways that can cause opportunistic infections of the airway mucosa including bronchopulmonary infections in patients with chronic obstructive pulmonary disease (COPD). It is clear that opportunistic infections contribute significantly to inflammatory exacerbations of COPD; however, there remains much to be learned regarding specific host and microbial determinants of persistence and/or clearance in this context.

Methods

In this study, we used a recently described ferret model for COPD, in which animals undergo chronic long-term exposure to cigarette smoke, to define host–pathogen interactions during COPD-related NTHi infections.

Results

NTHi bacteria colonised the lungs of smoke-exposed animals to a greater extent than controls, and elicited acute host inflammation and neutrophilic influx and activation, along with a significant increase in airway resistance and a decrease in inspiratory capacity consistent with inflammatory exacerbation; notably, these findings were not observed in air-exposed control animals. NTHi bacteria persisted within multicellular biofilm communities within the airway lumen, as evidenced by immunofluorescent detection of bacterial aggregates encased within a sialylated matrix as is typical of NTHi biofilms and differential bacterial gene expression consistent with the biofilm mode of growth.

Conclusions

Based on these results, we conclude that acute infection with NTHi initiates inflammatory exacerbation of COPD disease. The data also support the widely held hypothesis that NTHi bacteria persist within multicellular biofilm communities in the lungs of patients with COPD.

Infection of smoke-exposed ferrets with COPD results in mucus obstruction and respiratory symptoms as in patients, and the bacteria are in a distinct mode of growth consistent with biofilmshttps://bit.ly/3euXpbQ

Effect of acupuncture on chronic bronchitis: A protocol for systematic review and meta-analysis

INTRODUCTION

Chronic bronchitis (CB) is a clinically common and recurrent respiratory disease. However, many trials have shown that acupuncture can effectively treat CB. There is currently no systematic review of this therapy. The plan is to evaluate the effectiveness and safety of this treatment in patients with CB.

METHODS AND ANALYSIS

This systematic evaluation will entail an electronic and manual search of all acupuncture for CB from inception to December 31, 2020, regardless of the publication status or language. Databases include PubMed, Embase, Springer, Web of Science, the Cochrane Library, the World Health Organization International Clinical Trial Registration Platform, the Chinese Medicine Database, the China National Knowledge Infrastructure, the Chinese Biomedical Literature Database, the China Science Journal Database, and the Wanfang Database. Other sources of information, including bibliographies and meeting minutes for identified publications, will also be searched. A manual search for grey literature, including unpublished conference articles will be performed. Additionally, any clinical randomized controlled trials related to acupuncture for CB, regardless of the publication status and language limitations, will be included in the study. Study selection, data extraction, and research quality assessments will be conducted independently by 2 researchers. The main result was the Change in cystic fibrosis transmembrane conductance regulator function as measured by sweat chloride analysis or treatment effect. Secondary outcomes included Quality of life (eg, SF-36), change in Breathlessness, Cough, and Sputum Scale score, follow-up relapse rate, and adverse events. The system searches for randomized controlled trials of this therapy for CB. Implement the Cochrane RevMan V5.3 bias assessment tool to assess bias risk, data integration risk, meta-analysis risk, and subgroup analysis risk (if conditions are met). Mean difference, standard mean deviation, and binary data will be used to represent continuous results.

RESULTS

This study will provide a comprehensive review and evaluation of the available evidence for the treatment of CB using this therapy.

CONCLUSION

This study will provide new evidence to evaluate the effectiveness and side effects of acupuncture on CB. Because the data are not personalized, no formal ethical approval is required.

PROSPERO REGISTRATION NUMBER

CRD42020170287.

Prevalence of Chronic Bronchitis and Respiratory Health Profile of a Population Exposed to Wood Smoke in Nicaragua

BACKGROUND

Household air pollution (HAP) is one of the most important environmental risk factors worldwide associated with chronic respiratory diseases.

OBJECTIVES

The present study focused on respiratory health in a population with high wood smoke exposure in Nicaragua.

METHODS

We employed a cross-sectional study with 213 participants. Data on the prevalence of chronic bronchitis (chronic bronchitis), chronic obstructive pulmonary disease (COPD) and asthma, including respiratory scores and pulmonary function tests, were documented. The role of risk factors for chronic bronchitis was analyzed.

RESULTS

We found a high prevalence of chronic airway diseases in the population exposed to wood smoke. A higher prevalence of chronic bronchitis was found in persons serving as primary cooks in households. Further confounding factors for chronic bronchitis included age, a prior diagnosis of asthma, inhalational allergies and lower socioeconomic status. Respiratory scores were elevated in individuals with chronic bronchitis.

CONCLUSIONS

This is one of the first studies in a wood smoke-exposed population in Nicaragua showing a high prevalence of chronic bronchitis and COPD with an emphasis on the analysis of personal and environmental risk factors. Further studies are needed to address which combination of interventions is most efficient for ameliorating respiratory health hazards.

PARTICIPANT CONSENT

Obtained.

ETHICS APPROVAL

The study protocol was approved by the Ethics Committee of the University of Luebeck, Germany (reference number 12-214), and by the Ethics Committee of the Department of Medical Sciences at National Autonomous University of Nicaragua, Managua, Nicaragua.

COMPETING INTERESTS

The authors declare no competing financial interests.

Impact of baseline symptoms and health status on COPD exacerbations in the FLAME study

BACKGROUND

COPD is a heterogeneous disease and patients may respond differently to therapies depending on baseline symptom burden.

METHODS

This post-hoc analysis from the 52-week FLAME study investigated the impact of baseline symptom burden in terms of health status, dyspnoea, bronchitis status, eosinophil levels and smoking status on the subsequent risk of moderate or severe exacerbations. Health status was measured by St. George's Respiratory Questionnaire (SGRQ) score (higher ≥46.6 and lower < 46.6) and COPD Assessment Test (CAT) score (higher ≥17 and lower < 17); dyspnoea and bronchitis were assessed via an electronic diary (eDiary). Differential response to once-daily indacaterol/glycopyrronium (IND/GLY) 110/50 μg versus twice-daily salmeterol/fluticasone (SFC) 50/500 μg was assessed.

RESULTS

Data from 3354 patients was analysed. The risk of exacerbations was lower in patients who had less severe health impairment (rate ratio [RR] [95% CI]): SGRQ-C, (0.88 [0.78, 0.99]); CAT, 0.85 [0.75, 0.96]) and lower dyspnoea (0.79 [0.69, 0.90]) at baseline versus those with more severe health impairment and higher dyspnoea, respectively. Compared with SFC, IND/GLY led to better prevention of moderate-to-severe exacerbations in the majority of groups studied.

CONCLUSION

Patients with more severe health status impairment and greater symptom burden at baseline subsequently experienced more exacerbations in the FLAME study. IND/GLY was overall more effective in preventing exacerbations versus SFC, regardless of baseline symptom burden. Our results suggest that future studies on novel exacerbation therapies should consider targeting patients with higher symptom burden at baseline.

CLINICAL TRIAL IDENTIFIER

NCT01782326.

Association of birthplace and occupational exposures with chronic bronchitis in US Hispanics/Latinos, 2008-2011

OBJECTIVES

In the US, chronic bronchitis (CB) is common and is associated with substantial morbidity and mortality. Data on CB in the Hispanic/Latino population-a large, diverse US minority-are scarce. We aimed to test whether the prevalence of CB varies across Hispanic/Latino heritages and to identify CB risk factors, including occupational exposures, in this population.

METHODS

We analysed data from the Hispanic Community Health Study/Study of Latinos, a US population-based probability sample of participants aged 18-74 years (n=16 415) including those with Mexican, Puerto Rican, Dominican, Cuban, Central American and South American heritages. Participants who had a completed respiratory questionnaire and valid spirometric data were included in the analysis (n=13 259). CB, place of birth, heritage, occupational exposures and other risk factors were based on standardised questionnaires. The prevalence of CB was estimated using survey logistic regression-conditional marginal analysis.

RESULTS

The estimated (mean (95% CI)) overall adjusted prevalence of CB was 12.1% (9.3 to 15.6), with a large variation across heritages. Dominican heritage had a fivefold higher prevalence than South American heritage. US-born participants had a higher adjusted prevalence than their non-US-born counterparts (16.8% (12.5 to 22.1) vs 11.0% (8.5 to 14.10); p=0.022). Compared with non-exposed participants, those exposed to cleaning or disinfecting solutions had a higher adjusted prevalence of CB (12.6% (9.1 to 17.1) vs 11.8% (9.2 to 15.1); p=0.024).

CONCLUSIONS

The prevalence of CB was higher among Dominicans than other Hispanic/Latino heritages. CB was more prevalent among US-born participants and those exposed to cleaning and disinfecting solutions.

Chronic Diseases Multimorbidity among Adult People Living with HIV at Hawassa University Comprehensive Specialized Hospital, Southern Ethiopia

Background

Due to the wide implementation of antiretroviral therapy (ART), people living with HIV (PLWHIV) are now living longer. This increased the risk of developing noncommunicable chronic diseases (NCCDs) among them.

Objective

We aimed to describe prevalence of NCCDs multimorbidity among PLWHIV at Hawassa University Comprehensive Specialized Hospital (HUCSH).

Method

In April 2016, institution-based cross-sectional study was conducted among PLWHIV, aged ≥ 18 years at the ART unit of HUCSH. A nurse working in the ART unit interviewed patients and reviewed medical records. Data on the NCCDs and its risk factors were obtained. List of diseases considered in this study were arthritis, diabetes mellitus, hypertension, congestive heart failure (CHF), rheumatic heart diseases (RHD), chronic bronchitis, asthma, and cancer.

Results

More than half of the respondents (196) had at least one of the NCCDs and 34 (8.9%) had multimorbidity. The main system of the body affected were the musculoskeletal system, 146 (38.2%) and respiratory system, 46 (12.0%). There was no significant difference in the prevalence of individual NCCDs by gender. Patients aged above 44 years, patients with ART duration of at least 6 years, and patients with higher CD4 counts had increased odds of having any one of the NCCDs. Multimorbidity patients with a longer ART duration had an increased risk.

Conclusion

The prevalence of NCCD multimorbidity among PLWHIV was high. Monitoring the occurrence of NCCDs among PLWHIV and noncommunicable disease care is recommended.

CAT Score and SGRQ Definitions of Chronic Bronchitis as an Alternative to the Classical Definition

Purpose

Previous studies have used various definitions to classify chronic obstructive pulmonary disease (COPD) patients into chronic bronchitis (CB) and non-CB patients. This study was performed to identify differences among three definitions of CB based on the classical method, St. George's Respiratory Questionnaire (SGRQ), and the CAT (COPD Assessment Test) score.

Patients and methods

We extracted data from the multicenter Korea COPD Subgroup Study (KOCOSS) cohort, for which patients recruited from among 47 medical centers in South Korea beginning in April 2012. Patients were classified according to three different definitions of CB: 1) classical definition; 2) SGRQ (using questions regarding cough and sputum); and 3) CAT score (comprising cough [CAT1] and sputum [CAT2] subscale scores).

Results

A total of 2694 patients were enrolled in this study. The proportions of CB were 10.8%, 35.8%, and 24.0% according to the classical, SGRQ, and CAT definitions, respectively. The three definitions yielded consistently significant differences between CB and non-CB patients in modified Medical Research Council dyspnea scale CAT score, SGRQ score, number of moderate-to-severe exacerbations per year and forced expiratory volume in 1 second. By three definitions, CB consistently predicted future risk of exacerbation. The kappa coefficient of agreement between the classical definition and SGRQ definition was 0.29, that of the classical definition and CAT definition was 0.32, and that of the SGRQ definition and CAT definition was 0.44.

Conclusion

Patients with CB according to the new definitions based on SGRQ or CAT score showed similar clinical characteristics to those defined according to the classical definition. The new CB definitions may be used as alternatives to the classical definition.

Epithelial-Immune Cell Interactions for Drug Discovery in Chronic Obstructive Pulmonary Disease

New studies of chronic obstructive pulmonary disease (COPD) are revealing the key role of airway epithelial cells and innate immune cells in the initiation, exacerbation, and progression of airway disease. An emerging scheme focuses on expansion of airway progenitor epithelial cells that feed forward for a type 2 immune response and consequent IL-13-driven mucus production that is linked to the morbidity and mortality of COPD. Analysis of human airway progenitor epithelial cells and airway tissue shows that IL-13 signaling to MUC5AC mucin gene expression relies on specific activation of mitogen-activated protein kinase 13, providing a druggable target for attenuating mucus production in the setting of viral infection and other inhaled stimuli of airway inflammation. Moreover, structure-based drug design is delivering highly potent, selective, and nontoxic small-molecule kinase inhibitors of mitogen-activated protein kinase 13 that offer a therapeutic strategy to downregulate excess mucus production to a physiological level and thereby achieve a precision medicine solution to the major health care problem of COPD and related airway diseases.

Establishment of rapid risk assessment model for cigarette smoke extract exposure in chronic obstructive pulmonary disease

Rapid risk assessment models for different types of cigarette smoke extract (CSE) exposure are critical to understanding the etiology of chronic obstructive pulmonary disease. The present study investigated inflammation of cultured tracheal tissues with CSE exposure. Rat trachea rings were isolated, cultured, then exposed to various concentrations of CSE from 3R4 F reference cigarettes for 4 h. Tissue/cellular morphology, ultrastructure, viability and damage, inflammatory cell infiltration, and inflammatory protein levels were measured and compared to untreated controls. Human bronchial epithelial cells (BEAS-2B) exposed to 0 or 300 μg/mL CSE were cocultured with macrophages to assess extent of mobilization and phagocytosis. Endotracheal epithelium cilia densities were significantly reduced with increasing CSE concentrations, while mucous membranes became increasingly disordered; both eventually disappeared. Macrophages became larger as the CSE concentration increased, with microvilli and extended pseudopodium covering their surface, and many primary and secondary lysosomes present in the cytoplasm. Inflammatory cell infiltration also increased with increasing CSE dose, as did intracellular adhesion molecule-1(ICAM-1), interleukin-6(IL-6). The method described here may be useful to qualitatively characterized the effects of the compound under study. Then, we use BEAS-2B cell line system to strength the observation made in the cultured tissues. Probably, an approach to integrate results from both experiments will facilitate its application. These results demonstrate that cultured rat tracheal rings have a whole-tissue structure that undergoes inflammatory processes similar to in vivo tissues upon CSE exposure.

Evaluation of lung parenchyma, blood vessels, and peripheral blood lymphocytes as a potential source of acute phase reactants in patients with COPD

Background: Previous studies have shown that the arterial wall is a potential source of inflammatory markers in COPD. Here, we sought to compare the expression of acute phase reactants (APRs) in COPD patients and controls both at the local (pulmonary arteries and lung parenchyma) and systemic (peripheral blood leukocytes and plasma) compartments. Methods: Consecutive patients undergoing elective surgery for suspected primary lung cancer were eligible for the study. Patients were categorized either as COPD or control group based on the spirometry results. Pulmonary arteries and lung parenchyma sections, peripheral blood leukocytes, and plasma samples were obtained from all participants. Gene expression levels of C-reactive protein (CRP) and serum amyloid A (SAA1, SAA2, and SAA4) were evaluated in tissue samples and peripheral blood leukocytes by reverse transciption-PCR. Plasma CRP and SAA protein levels were measured by enzyme-linked immunosorbent assays. Proteins were evaluated in paraffin-embedded lung tissues by immunohistochemistry. Results: A total of 40 patients with COPD and 62 controls were enrolled. We did not find significant differences in the gene expression between COPD and control group. Both CRP and SAA were overexpressed in the lung parenchyma compared with pulmonary arteries and peripheral blood leukocytes. The expression of SAA was significantly higher in the lung parenchyma than in the pulmonary artery (2-fold higher for SAA1 and SAA4, P=0.015 and P<0.001, respectively; 8-fold higher for SAA2, P<0.001) and peripheral blood leukocytes (16-fold higher for SAA1, 439-fold higher for SAA2, and 5-fold higher for SAA4; P<0.001). No correlation between plasma levels of inflammatory markers and their expression in the lung and peripheral blood leukocytes was observed. Conclusions: The expression of SAA in lung parenchyma is higher than in pulmonary artery and peripheral blood leukocytes. Notably, no associations were noted between lung expression of APRs and their circulating plasma levels, making the leakage of inflammatory proteins from the lung to the bloodstream unlikely. Based on these results, other potential sources of systemic inflammation in COPD (eg, the liver) need further scrutiny.

The St. George's Respiratory Questionnaire Definition of Chronic Bronchitis May Be a Better Predictor of COPD Exacerbations Compared With the Classic Definition

BACKGROUND

Chronic bronchitis (CB) increases risk of COPD exacerbations. We have shown that the St. George's Respiratory Questionnaire (SGRQ) CB definition identifies patients with a similar clinical phenotype as classically defined CB. Whether the SGRQ CB definition is a predictor of future COPD exacerbations is unknown.

METHODS

We analyzed 7,557 smokers with normal spirometry and Global Initiative for Chronic Obstructive Lung Disease stage 1-4 COPD in the Genetic Epidemiology of COPD study with longitudinal follow-up data on exacerbations. Subjects were divided into classic CB⁺ or classic CB^-, using the classic definition. In addition, subjects were divided into SGRQ CB⁺ or SGRQ CB^-. Exacerbation frequency and severe exacerbation frequency were determined in each group. Multivariable linear regressions were performed for exacerbation frequency with either classic CB or SGRQ CB and relevant covariates.

RESULTS

There were 1,434 classic CB⁺ subjects and 2,290 SGRQ CB⁺ subjects. The classic CB⁺ group had a greater exacerbation frequency compared with the classic CB^- group (0.69 ± 1.26 vs 0.36 ± 0.90 exacerbations per patient per year; P < .0001) and a greater severe exacerbation frequency (0.26 ± 0.74 vs 0.13 ± 0.46 severe exacerbations per patient per year; P < .0001). There were similar differences between the SGRQ CB⁺ and SGRQ CB^- groups. In multivariable analysis, both SGRQ CB and classic CB were independent predictors of exacerbation frequency, but SGRQ CB had a higher regression coefficient. In addition, SGRQ CB was an independent predictor of severe exacerbation frequency whereas classic CB was not.

CONCLUSIONS

The SGRQ CB definition identified more subjects at risk for future exacerbations than the classic CB definition. SGRQ CB was at least a similar if not better predictor of future exacerbations than classic CB.

The Spectrum of Non-asthmatic Airway Diseases Contributing to Cough in the Adult

PURPOSE OF REVIEW

Cough becomes a pathologic reflex when the airways are inflamed and overwhelmed with excessive mucus. The goal of this review is to discuss acute and chronic cough syndromes caused by non-asthmatic airway diseases.

RECENT FINDINGS

Acute cough syndrome is short-lived and self-limited. Acute bronchitis and diffuse acute infectious bronchiolitis (DAIB) are examples. The former is usually caused by a viral illness; the latter by Mycoplasma pneumoniae, influenza, and Haemophilus influenzae. Causes of chronic cough in the adult include chronic bronchitis, non-infectious bronchiolitis, and non-cystic fibrosis bronchiectasis.

SUMMARY

Supportive measures are recommended for acute bronchitis and antibiotic use is discouraged. Antibiotics may be needed for DAIB. Smoking cessation and bronchodilators can control cough in chronic bronchitis. Therapeutic approaches for non-infectious bronchiolitis depend on the varied etiology. The hallmark of bronchiectasis is a chronic infection of the airways, and antibiotics, mucus clearance measures, and bronchodilators are all supportive.

Construction of a Suite of Computable Biological Network Models Focused on Mucociliary Clearance in the Respiratory Tract

Mucociliary clearance (MCC), considered as a collaboration of mucus secreted from goblet cells, the airway surface liquid layer, and the beating of cilia of ciliated cells, is the airways’ defense system against airborne contaminants. Because the process is well described at the molecular level, we gathered the available information into a suite of comprehensive causal biological network (CBN) models. The suite consists of three independent models that represent (1) cilium assembly, (2) ciliary beating, and (3) goblet cell hyperplasia/metaplasia and that were built in the Biological Expression Language, which is both human-readable and computable. The network analysis of highly connected nodes and pathways demonstrated that the relevant biology was captured in the MCC models. We also show the scoring of transcriptomic data onto these network models and demonstrate that the models capture the perturbation in each dataset accurately. This work is a continuation of our approach to use computational biological network models and mathematical algorithms that allow for the interpretation of high-throughput molecular datasets in the context of known biology. The MCC network model suite can be a valuable tool in personalized medicine to further understand heterogeneity and individual drug responses in complex respiratory diseases.

Occupational exposures and incidence of chronic bronchitis and related symptoms over two decades: the European Community Respiratory Health Survey

OBJECTIVES

Chronic bronchitis (CB) is an important chronic obstructive pulmonary disease (COPD)-related phenotype, with distinct clinical features and prognostic implications. Occupational exposures have been previously associated with increased risk of CB but few studies have examined this association prospectively using objective exposure assessment. We examined the effect of occupational exposures on CB incidence in the European Community Respiratory Health Survey.

METHODS

Population samples aged 20-44 were randomly selected in 1991-1993, and followed up twice over 20 years. Participants without chronic cough or phlegm at baseline were analysed. Coded job histories during follow-up were linked to the ALOHA Job Exposure Matrix, generating occupational exposure estimates to 12 categories of chemical agents. Their association with CB incidence over both follow-ups was examined with Poisson models using generalised estimating equations.

RESULTS

8794 participants fulfilled the inclusion criteria, contributing 13 185 observations. Only participants exposed to metals had a higher incidence of CB (relative risk (RR) 1.70, 95% CI 1.16 to 2.50) compared with non-exposed to metals. Mineral dust exposure increased the incidence of chronic phlegm (RR 1.72, 95% CI 1.43 to 2.06). Incidence of chronic phlegm was increased in men exposed to gases/fumes and to solvents and in women exposed to pesticides.

CONCLUSIONS

Occupational exposures are associated with chronic phlegm and CB, and the evidence is strongest for metals and mineral dust exposure. The observed differences between men and women warrant further investigation.

Fibrinogen as a potential biomarker for clinical phenotype in patients with chronic obstructive pulmonary disease

Background

Under the Food and Drug Administration's drug development tool qualification program, fibrinogen is the first biomarker drug development tool used in chronic obstructive pulmonary disease (COPD). However, the correlation between fibrinogen and exacerbations among Korean patients with COPD remains unclear.

Methods

In this retrospective cross-sectional study, we included patients with COPD for whom plasma fibrinogen assessment results, without exacerbation, were available. Then, we compared subgroups according to fibrinogen level (threshold: 350 mg/dL). We used multivariate linear regression analysis to investigate the clinical phenotype of COPD with high fibrinogen level, analyzed the correlation between the COPD severity indexes and fibrinogen level.

Results

Of 140 patients, we confirmed 48 (34.3%) patients in the high-level fibrinogen group. The high-level group demonstrated a medical history of more exacerbations than the low-level group. Lung functions [forced expiratory volume in 1 s (FEV₁), forced vital capacity, and 6-minute walk distance] were more deteriorated in the high-level group. Multivariate regression analysis revealed that fibrinogen level was associated with high COPD assessment test score, and experience of exacerbation. Fibrinogen level exhibited a statistically significant positive correlation with COPD severity indexes.

Conclusions

High fibrinogen level seems to reflect frequent exacerbation and severe symptomatic phenotypes in Korean patients with COPD.

COPD phenotypes: differences in survival

Background

The aim of the study was to analyze the characteristics and survival of a group of patients with COPD according to their clinical phenotype.

Patients and methods

The study population was selected from patients undergoing scheduled spirometry between January 1, 2011 and June 30, 2011 at the respiratory function laboratory of a teaching hospital and comprised those with a previous and confirmed diagnosis of COPD and forced expiratory volume in the first second (FEV₁) of <70%. The patients selected were classified into 4 groups: positive bronchodilator response, non-exacerbator, exacerbator with emphysema, and exacerbator with chronic bronchitis. Patients were followed up until April 2017.

Results

We recruited 273 patients, of whom 89% were men. The distribution by phenotype was as follows: non-exacerbator, 47.2%; positive bronchodilator response, 25.8%; exacerbator with chronic bronchitis, 13.8%; and exacerbator with emphysema, 13.0%. A total of 90 patients died during follow-up (32.9%). Taking patients with a positive bronchodilator response as the reference category, the risk factors that were independently associated with death were older age (HR, 1.06; 95% CI, 1.03-1.09), lower FEV₁ (HR, 0.98; 95% CI, 0.96-0.99), and exacerbator with chronic bronchitis phenotype (HR, 3.28; 95% CI, 1.53-7.03).

Conclusion

Classification of COPD patients by phenotype makes it possible to identify subgroups with different prognoses. Thus, mortality was greater in exacerbators with chronic bronchitis and lower in those with a positive bronchodilator response.

Different Pattern of Chronic Obstructive Pulmonary Disease Assessment Test Score between Chronic Bronchitis and Non-chronic Bronchitis Patients

BACKGROUND

Chronic bronchitis (CB) is an important phenotype in chronic obstructive pulmonary disease (COPD). The purpose of this study is to evaluate different pattern of COPD assessment test (CAT) score between CB and non-CB patients.

METHODS

Patients were recruited from 45 centers in Korea, as part of the Korean COPD Subgroup Study cohort. CB was defined when sputum continued for at least 3 months.

RESULTS

Total 958 patients with COPD were eligible for analysis. Among enrolled patients, 328 (34.2%) were compatible with CB. The CAT score was significantly higher in patients with CB than non-CB, and each component of CAT score showed a similar result. CB was significantly associated with CAT score when adjusted with age, sex, modified Medical Research Council, and post-bronchodilator forced expiratory volume in 1 second. Each component of CAT score between patients with CB and non-CB showed different pattern according to Global Initiative for Chronic Obstructive Lung Disease grade.

CONCLUSION

CAT score is significantly higher in patients with CB than non-CB. Each component of CAT score was significantly different between two groups.

Chronic bronchitis: High prevalence in never smokers and underdiagnosis- A population-based study in Colombia

The objective of the article was to establish the prevalence, underdiagnosis, and risk factors of chronic bronchitis (CB) in a general population in five Colombian cities. Cross-sectional study using a probabilistic sampling technique in five Colombian cities was adopted. The CB definition was “cough and expectoration for three or more months per year for at least two consecutive years.” Underdiagnosis was considered in subjects with clinical definition without previous medical diagnosis. Univariate χ² or Student’s t-test and logistic regression analysis were used. The study included 5539 subjects. The prevalence was 5.5%, the underdiagnosis 50.3%, and 33.7% of the cases were in nonsmokers (53.6% in women vs. 16.9% in men, p < 0.001). The adjusted risk factors were living in Bogota, current smoking, male, age ≥ 64 years, low education, indoor wood smoke exposure, and occupational exposure to vapors, gases, dust, and fumes. CB is a common disease among adults in Colombia. The underdiagnosis was high and there were a large proportion of cases in nonsmokers, particularly in women. Our findings support the association of CB with indoor wood smoke and occupational exposures.

Epidemiology and impact of chronic bronchitis in chronic obstructive pulmonary disease

Research on the association between chronic bronchitis and chronic obstructive pulmonary disease (COPD) exacerbations has led to discordant results. Furthermore, the impact of chronic bronchitis on mortality in COPD subjects is unclear.Within the Rotterdam Study, a population-based cohort study of subjects aged ≥45 years, chronic bronchitis was defined as having a productive cough for ≥3 months per year for two consecutive years. Linear, logistic regression and Cox proportional hazard models were adjusted for age, sex and pack-years.Out of 972 included COPD subjects, 752 had no chronic phlegm production (CB-) and 220 had chronic phlegm production, of whom 172 met the definition of chronic bronchitis (CB+). CB+ subjects were older, more frequently current smokers and had more pack-years than CB- subjects. During a median 6.5 years of follow-up, CB+ subjects had greater decline in lung function (-38 mL·year-1, 95% CI -61.7--14.6; p=0.024). CB+ subjects had an increased risk of frequent exacerbations (OR 4.0, 95% CI 2.7-5.9; p<0.001). In females, survival was significantly worse in CB+ subjects compared to CB- subjects. Regarding cause-specific mortality, CB+ subjects had an increased risk of respiratory mortality (hazard ratio 2.16, 95% CI 1.12-4.17; p=0.002).COPD subjects with chronic bronchitis have an increased risk of exacerbations and respiratory mortality compared to COPD subjects without chronic phlegm production.

COPD assessment test score and serum C-reactive protein levels in stable COPD patients

BACKGROUND

An eight-item questionnaire of the COPD assessment test (CAT) is widely used to quantify the impact of COPD on the patient's health status. C-reactive protein (CRP) is associated with disease severity and adverse health outcomes of patients with COPD. This study aimed to evaluate the relationship between CAT score and serum CRP levels in stable COPD patients.

METHODS

We evaluated the medical records of 226 patients with CAT and serum CRP measured within a week at Samsung Medical Center between October 2013 and October 2015.

RESULTS

Serum CRP levels had a significantly positive relationship with CAT score (Spearman's r=0.20, P=0.003). Patients with elevated serum CRP levels (>0.3 mg/dL) were significantly more likely to have CAT scores of ≥14. The adjusted odds ratio for elevated serum CRP levels in total CAT score was 1.06 (95% confidence interval, 1.02-1.09). Among CAT components, cough (adjusted P=0.005), phlegm (adjusted P=0.001), breathlessness going up hills/stairs (adjusted P=0.005), low confidence leaving home (adjusted P=0.002), and feeling low in energy (adjusted P=0.019) were independently associated with elevated serum CRP levels.

CONCLUSION

In stable COPD patients, serum CRP levels were independently associated with total CAT score and CAT components related to respiratory symptoms, confidence leaving home, and energy.

Impact of Chronic Obstructive Pulmonary Disease on Long-Term Outcome in Patients with Coronary Artery Disease Undergoing Percutaneous Coronary Intervention

Objective. The aim of this study was to investigate the association between COPD and major adverse cardiovascular and cerebral events (MACCE) in patients undergoing percutaneous coronary intervention (PCI). Methods. 2,362 patients who underwent PCI were included in this study. Subjects were divided into 2 groups: with COPD (n = 233) and without COPD (n = 2,129). Cox proportional hazards models were analyzed to determine the effect of COPD on the incidence of MACCE. Results. The patients with COPD were older (P < 0.0001) and were more likely to be current smokers (P = 0.02) and have had hypertension (P = 0.02) and diabetes mellitus (P = 0.01). Prevalence of serious cardiovascular comorbidity was higher in the patients with COPD, including a history of MI (P = 0.02) and HF (P < 0.0001). Compared with non-COPD group, the COPD group showed a higher risk of all-cause death (hazard ratio (HR): 2.45, P < 0.0001), cardiac death (HR: 2.53, P = 0.0002), MI (HR: 1.387, P = 0.027), and HF (HR: 2.25, P < 0.0001). Conclusions. Patients with CAD and concomitant COPD are associated with a higher incidence of MACCE (all-cause death, cardiac death, MI, and HF) compared to patients without COPD. The patients with a history of COPD have higher in-hospital and long-term mortality rates than those without COPD after PCI.

Effect of ELOM-080 on exacerbations and symptoms in COPD patients with a chronic bronchitis phenotype - a post-hoc analysis of a randomized, double-blind, placebo-controlled clinical trial

Background

Treating symptoms and preventing exacerbations are key components of chronic obstructive pulmonary disease (COPD) long-term management. Recently, a more tailored treatment approach has been proposed, in particular for two well-established clinical phenotypes, frequent exacerbators and chronic bronchitis-dominant COPD. ELOM-080 has demonstrated clinical efficacy in treating symptoms and preventing exacerbations in subjects with chronic bronchitis. However, little is known about the potential effects of ELOM-080 in COPD patients.

Aim

To evaluate the effect on exacerbation, cough sputum, and general state of health of long-term treatment with ELOM-080 in COPD patients with an exacerbation history and chronic bronchitis.

Methods

We performed a post-hoc analysis of a randomized, double-blinded, placebo-controlled parallel-group clinical trial of a 6-month treatment with ELOM-080 (3×300 mg) in patients with chronic bronchitis and concomitant COPD. The primary outcome was the proportion of subjects with at least one exacerbation over the 6-month study period. Secondary outcomes included the total number of exacerbations (ie, cumulative occurrence of exacerbations during the study period) and the proportion of acute exacerbations necessitating an antibiotic treatment, monthly evaluations of sputum and cough symptoms, and the general state of health and a safety analysis.

Results

Of 260 randomized subjects, 64 patients fulfilled the inclusion criteria for COPD (ELOM-080: 35, placebo: 29). Compared to placebo, ELOM-080 reduced the percentage of subjects with at least one exacerbation (29% versus 55%, P=0.031) and a reduction in the overall occurrence of exacerbations (ELOM-080: 10, placebo: 21, P=0.012) during the winter season. The percentage of asymptomatic or mildly symptomatic patients (sputum/expectoration and cough) was consistently higher in the ELOM-080 group compared to placebo, with statistical significant differences after 2 and 3 months of treatment (2 months: ELOM-080 25%, placebo 11%, P<0.005; 3 months: ELOM-080 26%, placebo 14%, P<0.05). Likewise the subjective rating of general health status was better in the ELOM-080 group with statistically significant superiority after 2 and 3 months of treatment (2-month treatment: P=0.015; 3-month treatment: P=0.024). Tolerability results were comparable between ELOM-080 and placebo.

Conclusion

ELOM-080 is efficacious in patients with COPD and a chronic bronchitis phenotype. Prophylactic use reduces the rate of exacerbations and improves the key symptoms of sputum and cough with a favorable long-term tolerability profile.

Impact of current cough on health-related quality of life in patients with COPD

BACKGROUND

Cough and sputum production are frequent in chronic obstructive pulmonary disease (COPD). The objective of this study was to examine the relationship between cough and sputum production and health-related quality of life in COPD.

METHODS

A cross-sectional study was conducted in the French Initiatives COPD cohort and assessed cough and sputum production within the past 7 days using the cough and sputum assessment questionnaire (CASA-Q), health-related quality of life, spirometry, smoking status, dyspnea, exacerbations, anxiety and depression, and comorbidities.

RESULTS

One hundred and seventy-eight stable COPD patients were included (age, 62 [56-69] years, 128 male, forced expiratory volume in 1 second [FEV1]: 57 [37-72] % predicted) (median [Q1-Q3]). In univariate analyses, health-related quality of life (Saint George's respiratory questionnaire total score) was associated with each CASA-Q domain and with chronic bronchitis, exacerbations, dyspnea, FEV1, depression, and anxiety. All four domains introduced separately were independently associated with health-related quality of life. When introduced together in multivariate analyses, only the cough impact domain remained independently associated with health-related quality of life (R2=0.60). With chronic bronchitis (standard definition) instead of the CASA-Q, the R2 was lower (R2=0.54).

CONCLUSION

This study provides evidence that current cough in the previous 7 days is an important determinant of health-related quality of life impairment in stable COPD patients.