Chronic Obstructive Pulmonary Disease Phenotypes: Implications for Care

Five-Repetition Sit-to-Stand Test as Predictor of Mortality in High Risk COPD Patients

OBJECTIVE

To determine if adding performance on the five-repetition sit-to-stand test (5-STS) to chronic obstructive pulmonary disease (COPD) high-risk criteria, proposed by the Spanish COPD guidelines (GesEPOC), affects mortality prognosis.

METHODS

Observational study of COPD outpatients involved prospective follow-up for 5 years. Patients were classified based on 5-STS performance and risk criteria proposed by GesEPOC version 2021. Outcome measures were 5-year mortality timing and rate. Kaplan-Meier curves and univariate and multivariate Cox proportional-hazard analyses, analysis of variance, and univariate and multivariate linear and logistic regression models were used.

RESULTS

One hundred and thirty-seven patients were included. Mean age was 66±8.3 years, and 87.6% were men. Of them, 115 (83.9%) were classified as high risk, 43 (34.4%) of whom had poor performance on the 5-STS. Overall mortality at 5 years was 27% and was significantly higher in the high-risk (29.6%) compared with the low-risk (13.6%) group. Among high-risk patients, mortality at 5 years was significantly worse with poor 5-STS performance (60.5%) compared with non-poor performance (11.1%). Poor performance on the 5-STS was independently associated with increased 5-year mortality risk (HR 4.70; 95% CI: 1.96-11.27) in a model adjusted for history of heart disease and dyspnea.

CONCLUSION

Among high-risk COPD patients, those with poor performance on the 5-STS have a significantly higher mortality at 5 years than those with non-poor 5-STS performance.

Factors Affecting Survival in Severe and Very Severe COPD after Admission in ICUs of Tertiary Care Centers of India (FAST COPD): Study Protocol for a Multicentric Cohort Study

Background

Chronic obstructive pulmonary disease (COPD) is a leading cause of morbidity and mortality worldwide. However, there is a lack of comprehensive data from low- and middle-income countries (LMICs) regarding factors influencing COPD outcomes, particularly in regions where biomass exposure is prevalent.

Objective

The Factors Affecting Survival in Severe and Very Severe COPD Patients Admitted to Tertiary Centers of India (FAST) study aims to address this gap by evaluating factors impacting survival and exacerbation rates among COPD patients in LMICs like India, with a specific focus on biomass exposure, clinical phenotypes, and nutritional status in patients admitted to the Intensive Care Unit (ICU).

Methods

The FAST study is an observational cohort study conducted in university teaching hospitals across India. The study aims to enroll 1000 COPD patients admitted to the ICU meeting specific inclusion criteria, with follow-up assessments conducted every 6 months over a 2-year period. Data collection includes demographic information, clinical manifestations, laboratory investigations, pulmonary function tests, medications, nutritional status, mental health, and health-related quality of life. Adjudication of exacerbations and mortality will also be undertaken. The FAST study seeks to provide crucial insights into COPD outcomes in LMICs, informing more precise management strategies and mitigating the burden of COPD in these settings. By evaluating factors such as biomass exposure, clinical phenotypes, and nutritional status, the study aims to address key knowledge gaps in COPD research.

How to cite this article

Arunachala S, Devapal S, Swamy DSN, Greeshma MV, Ul Hussain I, Siddaiah JB, et al. Factors Affecting Survival in Severe and Very Severe COPD after Admission in ICUs of Tertiary Care Centers of India (FAST COPD): Study Protocol for a Multicentric Cohort Study. Indian J Crit Care Med 2024;28(6):552-560.

Reduced Tolerogenic Program Death-Ligand 1-Expressing Conventional Type 1 Dendritic Cells Are Associated with Rapid Decline in Chronic Obstructive Pulmonary Disease

BACKGROUND

Chronic obstructive pulmonary disease (COPD) is characterized, at least in part, by autoimmunity through amplified T helper 1 and 17 (Th1 and Th17) immune responses. The loss of immune tolerance controlled by programmed death-ligand 1 (PD-L1) may contribute to this.

OBJECTIVES

We studied the tolerogenic role of PD-L1+ dendritic cells (DCs) and their subtypes in relation to specific T cell immunity and the clinical phenotypes of COPD.

METHODS

We used flow cytometry to analyze PD-L1 expression by the DCs and their subtypes in the peripheral blood mononuclear cells (PBMCs) from normal participants and those with COPD. T cell proliferation and the signature cytokines of T cell subtypes stimulated with elastin as autoantigens were measured using flow cytometry and enzyme-linked immunosorbent assays (ELISA), respectively.

MEASUREMENT AND MAIN RESULTS

A total of 83 participants were enrolled (normal, n = 29; COPD, n = 54). A reduced PD-L1+ conventional dendritic cell 1 (cDC1) ratio in the PBMCs of the patients with COPD was shown (13.7 ± 13.7%, p = 0.03). The decrease in the PD-L1+ cDC1 ratio was associated with a rapid decline in COPD (p = 0.02) and correlated with the CD4+ T cells (r = -0.33, p = 0.02). This is supported by the NCBI GEO database accession number GSE56766, the researchers of which found that the gene expressions of PD-L1 and CD4, but not CD8 were negatively correlated from PBMC in COPD patients (r = -0.43, p = 0.002). Functionally, the PD-L1 blockade enhanced CD4+ T cell proliferation stimulated by CD3/elastin (31.2 ± 22.3%, p = 0.04) and interleukin (IL)-17A production stimulated by both CD3 (156.3 ± 54.7, p = 0.03) and CD3/elastin (148 ± 64.9, p = 0.03) from the normal PBMCs. The PD-L1 blockade failed to increase IL-17A production in the cDC1-depleted PBMCs. By contrast, there was no significant change in interferon (IFN)-γ, IL-4, or IL-10 after the PD-L1 blockade. Again, these findings were supported by the NCBI GEO database accession number GSE56766, the researchers of which found that only the expression of RORC, a master transcription factor driving the Th17 cells, was significantly negatively correlated to PD-L1 (r = -0.33, p = 0.02).

CONCLUSIONS

Circulating PD-L1+ cDC1 was reduced in the patients with COPD, and the tolerogenic role was suppressed with susceptibility to self-antigens and linked to rapid decline caused by Th17-skewed chronic inflammation.

Clinical utilization of airway inflammatory biomarkers in the prediction and monitoring of clinical outcomes in patients with chronic obstructive pulmonary disease

INTRODUCTION

Chronic obstructive pulmonary disease (COPD) accounts for 545 million people living with chronic respiratory disorders and is the third leading cause of morbidity and mortality around the world. COPD is a progressive disease, characterized by episodes of acute worsening of symptoms such as cough, dyspnea, and sputum production.

AREAS COVERED

Airway inflammation is a prominent feature of COPD. Chronic airway inflammation results in airway structural remodeling and emphysema. Persistent airway inflammation is a treatable trait of COPD and plays a significant role in disease development and progression. In this review, the authors summarize the current and emerging biomarkers that reveal the heterogeneity of airway inflammation subtypes, clinical outcomes, and therapeutic response in COPD.

EXPERT OPINION

Airway inflammation can be broadly categorized as eosinophilic (type 2 inflammation) and non-eosinophilic (non-type 2 inflammation) in COPD. Currently, blood eosinophil counts are incorporated in clinical practice guidelines to identify COPD patients who are at a higher risk of exacerbations and lung function decline, and who are likely to respond to inhaled corticosteroids. As new therapeutics are being developed for the chronic management of COPD, it is essential to identify biomarkers that will predict treatment response.

Frailty and its influence on mortality and morbidity in COPD: A Systematic Review and Meta-Analysis

Frailty increases vulnerability to adverse outcomes. Long-term conditions increase the risk of frailty. We searched PubMed, Web of Science, The Cochrane Library, EMBASE from inception to March 2022. Quality assessment was conducted using the NOS. Data was analysed in a pooled a random-effects meta-analysis. Our primary outcome was the impact of frailty on mortality in adults with Chronic Obstructive Pulmonary Disease (COPD) diagnosis according to the guidelines. Secondary outcomes were: frailty and association with readmissions, hospitalisations, exacerbation rates, and prevalence of frailty in COPD. We identified 25 studies, with 5882 participants. The median prevalence of frailty was 47% (IQR, 39.3-66.3%, range 6.4-72%). There was an association between COPD patients living with frailty and increased risk of mortality versus COPD patients without frailty (pooled OR, 4.21 (95% CI 2.99-5.93, I2 55%). A descriptive analysis of relationship between frailty and hospital readmission and all cause hospitalization showed positive associations. The relationship between frailty and the risk of exacerbation showed a pooled OR, 1.45 (95% CI 0.37-5.70, I2 80%). Frailty is significantly associated with higher mortality risk in COPD. Frailty is common in patients with COPD and its measurement should be considered in clinical practice to better characterise COPD.

Three-Month Variability of Commonly Evaluated Biomarkers in Clinically Stable COPD

Introduction

Clinical decisions in chronic obstructive pulmonary disease (COPD) treatment often utilize serially assessed physiologic parameters and biomarkers. To better understand the reliability of these tests, we evaluated changes in commonly assessed biomarkers over 3 months in patients with clinically stable COPD.

Methods

We performed an observational prospective cohort study of 89 individuals with clinically stable COPD, defined as no exacerbation history within 3 months of enrollment. Biomarkers included lung function and functional performance status, patient-reported outcomes of symptoms and health status, and blood markers of inflammation. The correlation between testing at baseline and at 3-month follow-up was reported as the intraclass correlation coefficient (ICC). "Outliers" had significant variability between tests, defined as >1.645 standard deviations between the two measurements. Differences in clinical features between outliers and others were compared.

Results

Participants with COPD (n = 89) were 70.5 ± 6.7 years old, 54 (61%) male, had a 40 pack-year smoking history with 24.7% being current smokers, and postbronchodilator forced expiratory volume in one second (FEV1) 62.3 ± 22.7% predicted. The biomarkers with excellent agreement between the initial and the follow-up measurements were FEV1 (ICC = 0.96), Saint George's Respiratory Questionnaire (SGRQ) (ICC = 0.98), COPD Assessment Test (CAT) (ICC = 0.93) and C-reactive protein (CRP) (ICC = 0.90). By contrast, parameters showing less robust agreement were 6-minute walking distance (ICC = 0.75), eosinophil count (ICC = 0.77), erythrocyte sedimentation rate (ICC = 0.75) and white blood cell count (ICC = 0.48). Individuals with greater variability in biomarkers reported chronic bronchitis more often and had higher baseline SGRQ and CAT scores.

Conclusion

Our study evaluated the stability of commonly assessed biomarkers in clinically stable COPD and showed excellent agreement between baseline and three-month follow-up values for FEV1, SGRQ, CAT and CRP. Individuals with chronic bronchitis and more symptomatic disease at baseline demonstrated greater variability in 3-month interval biomarkers.

Respiratory Care Management of COPD Exacerbations

A COPD exacerbation is characterized by an increase in symptoms such as dyspnea, cough, and sputum production that worsens over a period of 2 weeks. Exacerbations are common. Respiratory therapists and physicians in an acute care setting often treat these patients. Targeted O2 therapy improves outcomes and should be titrated to an SpO2 of 88-92%. Arterial blood gases remain the standard approach to assessing gas exchange in patients with COPD exacerbation. The limitations of arterial blood gas surrogates (pulse oximetry, capnography, transcutaneous monitoring, peripheral venous blood gases) should be appreciated so that they can be used wisely. Inhaled short-acting bronchodilators can be provided by nebulizer (jet or mesh), pressurized metered-dose inhaler (pMDI), pMDI with spacer or valved holding chamber, soft mist inhaler, or dry powder inhaler. The available evidence for the use of heliox for COPD exacerbation is weak. Noninvasive ventilation (NIV) is standard therapy for patients who present with COPD exacerbation and is supported by clinical practice guidelines. Robust high-level evidence with patient important outcomes is lacking for the use of high-flow nasal cannula in patients with COPD exacerbation. Management of auto-PEEP is the priority in mechanically ventilated patients with COPD. This is achieved by reducing airway resistance and decreasing minute ventilation. Trigger asynchrony and cycle asynchrony are addressed to improve patient-ventilator interaction. Patients with COPD should be extubated to NIV. Additional high-level evidence is needed before widespread use of extracorporeal CO2 removal. Care coordination can improve the effectiveness of care for patients with COPD exacerbation. Evidence-based practices improve outcomes in patients with COPD exacerbation.

The gut microbiome is a significant risk factor for future chronic lung disease

BACKGROUND

The gut-lung axis is generally recognized, but there are few large studies of the gut microbiome and incident respiratory disease in adults.

OBJECTIVE

We sought to investigate the association and predictive capacity of the gut microbiome for incident asthma and chronic obstructive pulmonary disease (COPD).

METHODS

Shallow metagenomic sequencing was performed for stool samples from a prospective, population-based cohort (FINRISK02; N = 7115 adults) with linked national administrative health register-derived classifications for incident asthma and COPD up to 15 years after baseline. Generalized linear models and Cox regressions were used to assess associations of microbial taxa and diversity with disease occurrence. Predictive models were constructed using machine learning with extreme gradient boosting. Models considered taxa abundances individually and in combination with other risk factors, including sex, age, body mass index, and smoking status.

RESULTS

A total of 695 and 392 statistically significant associations were found between baseline taxonomic groups and incident asthma and COPD, respectively. Gradient boosting decision trees of baseline gut microbiome abundance predicted incident asthma and COPD in the validation data sets with mean area under the curves of 0.608 and 0.780, respectively. Cox analysis showed that the baseline gut microbiome achieved higher predictive performance than individual conventional risk factors, with C-indices of 0.623 for asthma and 0.817 for COPD. The integration of the gut microbiome and conventional risk factors further improved prediction capacities.

CONCLUSIONS

The gut microbiome is a significant risk factor for incident asthma and incident COPD and is largely independent of conventional risk factors.

Chronic moderate hypercapnia suppresses ventilatory responses to acute CO<sub>2</sub> challenges

Chronic hypercapnia (CH) is a hallmark of chronic lung disease, and CH increases the risk for acute-on-chronic exacerbations leading to greater hypoxemia/hypercapnia and poor health outcomes. However, the role of hypercapnia per se (duration and severity) in determining an individual's ability to tolerate further hypercapnic exacerbations is unknown. Our primary objective herein was to test the hypothesis that mild-to-moderate CH (arterial [Formula: see text] ∼50-70 mmHg) increases susceptibility to pathophysiological responses to severe acute CO₂ challenges. Three groups (GR) of adult female goats were studied during 14 days of exposure to room air (<i>GR 1</i>; control) or 6% inspired CO₂ (<i>GR 2</i>; mild CH), or 7 days of 6% inspired CO₂ followed by 7 days of 8% inspired CO₂ (<i>GR 3</i>; moderate CH). Consistent with previous reports, there were no changes in physiological parameters in <i>GR 1</i> (RA control), but mild CH (<i>GR 2</i>) increased steady-state ventilation and transiently suppressed CO₂/[H⁺] chemosensitivity. Further increasing InCO₂ from 6% to 8% (<i>GR 3</i>) transiently increased ventilation and arterial [H⁺]. Similar to mild CH, moderate CH increased ventilation to levels greater than predicted. However, in contrast to mild CH, acute ventilatory chemosensitivity was suppressed throughout the duration of moderate CH, and the arterial - mixed expired CO₂ gradient became negative. These data suggest that moderate CH limits physiological responses to acute severe exacerbations and provide evidence of recruitment of extrapulmonary systems (i.e., gastric CO₂ elimination) during times of moderate-severe hypercapnia.<b>NEW &amp; NOTEWORTHY</b> Moderate levels of chronic hypercapnia (CH; ∼70 mmHg) in healthy adult female goats elicited similar steady-state physiological adaptations compared with mild CH (∼55 mmHg). However, unlike mild CH, moderate CH chronically suppressed acute CO₂/[H⁺] chemosensitivity and reversed the arterial to mixed expired CO₂ gradient. These findings suggest that moderate CH suppresses vital mechanisms of ventilatory control and recruits additional physiological systems (i.e., gastric CO₂ release) to help buffer excess CO₂.

Impact of nutrition and physical activity on outcomes of hospital-acquired pneumonia

Frailty is an important risk factor for adverse health-related outcomes. It is classified into several phenotypes according to nutritional state and physical activity. In this context, we investigated whether frailty phenotypes were related to clinical outcome of hospital-acquired pneumonia (HAP). During the study period, a total of 526 patients were screened for HAP and 480 of whom were analyzed. The patients were divided into four groups according to physical inactivity and malnutrition: nutritional frailty (Geriatric Nutritional Risk Index [GNRI] < 82 and Clinical Frailty Scale [CFS] ≥ 4), malnutrition (GNRI < 82 and CFS < 4), physical frailty (GNRI ≥ 82 and CFS ≥ 4), and normal (GNRI ≥ 82 and CFS < 4). Among the phenotypes, physical frailty without malnutrition was the most common (39.4%), followed by nutritional frailty (30.2%), normal (20.6%), and malnutrition (9.8%). There was a significant difference in hospital survival and home discharge among the four phenotypes (p = 0.009), and the nutritional frailty group had the poorest in-hospital survival and home discharge (64.8% and 34.6%, respectively). In conclusion, there were differences in clinical outcomes according to the four phenotypes of HAP. Assessment of frailty phenotypes during hospitalization may improve outcomes through adequate nutrition and rehabilitation treatment of patients with HAP.

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.

The Impact of Air Pollution on Frequent Exacerbations among COPD Patients: An Observational Study on the Population of Western Romania

Patients with respiratory pathologies are the risk group most affected by air pollution, being directly exposed, especially those diagnosed with chronic obstructive pulmonary disease (COPD). In this observational study, which included 79 patients, we evaluated whether COPD patients with the frequent exacerbating phenotype or the infrequent exacerbating phenotype live in residences with higher values of air pollution. An air quality monitoring station was installed in each patient’s house for at least 24 h and PM 1.0, PM 2.5, and PM 10 were measured. Average PM 1.0, PM 2.5, and PM 10 values were lower in the group of infrequently exacerbating patients compared to the frequently exacerbating ones. For every 1 µg/m3 increase in the average values of PM 1.0, PM 2.5, and PM 10, there is an increase of 1.7%, 1.8% and 1%, respectively, in the risk of developing exacerbations. More importantly, an average value of PM 1.0, PM 2.5, and PM 10 above 32.21 µg/m3, 82.32 µg/m3 and 42.89 µg/m3 increases the probability of developing an exacerbation by 3.83, 10.14, and 4.12 times, respectively. Our analysis showed that COPD patients with a frequently exacerbating phenotype live in residences with high levels of air pollution compared to infrequently exacerbating ones.

Age- and gender-based comorbidity categories in general practitioner and pulmonology patients with COPD

Chronic obstructive pulmonary disease (COPD) is a debilitating medical condition often accompanied by multiple chronic conditions. COPD is more frequent among older adults and affects both genders. The aim of the current cross-sectional survey was to characterize chronic comorbidities stratified by gender and age among patients with COPD under the care of general practitioners (GP) and pulmonologists, using real-world patient data. A total of 7966 COPD patients (women: 45%) with more than 5 years of the observation period in the practice were examined using 60 different Chronic comorbid conditions (CCC) and Elixhauser measures. More than 9 in 10 patients had at least one, and 51.7% had more than three comorbidities. No gender difference was found in the number of comorbidities. However, men had higher Elixhauser-van Walraven index scores than women, and the types of comorbidities differed by gender. An increasing number of comorbidities was seen with aging but the patients in their 30s and 40s also had a high number of comorbidities. Moreover, GP patients had a higher number and a wider array of documented comorbidities than pulmonology patients did. Psychological comorbidities were common in all patients, but particularly among younger patients. These findings around gender- and age-stratified comorbidities under the care of GPs and pulmonologists have implications for the choice of data provenience for decision-making analysis and treatment selection and success.

Role of Short-Chain Fatty Acids Produced by Gut Microbiota in Innate Lung Immunity and Pathogenesis of the Heterogeneous Course of Chronic Obstructive Pulmonary Disease

Chronic obstructive pulmonary disease (COPD) is a widespread socially significant disease. The development of COPD involves the innate immune system. Interestingly, the regulation of the innate lung immune system is related to the gut microbiota. This connection is due to the production by gut microorganisms of short-chain fatty acids (SCFAs) such as acetate, propionate, and butyrate. Nutritional disturbances and changes in the structure of the intestinal microbiota lead to a decrease in SCFAs production and their effect on pulmonary immunity. The presence of a metabolic and immune axis linking the lungs and gut plays an important role in the pathogenesis of COPD. In addition, the nature of nutrition and SCFAs may participate in the development of the clinically heterogeneous course of COPD.

Sputum Bacterial Metacommunities in Distinguishing Heterogeneity in Respiratory Health and Disease

Background and Objective

Cluster-based analysis, or community typing, has been attempted as a method for studying the human microbiome in various body niches with the aim of reducing variations in the bacterial composition and linking the defined communities to host health and disease. In this study, we have presented the bacterial subcommunities in the healthy and the diseased population cohorts and have assessed whether these subcommunities can distinguish different host health conditions.

Methods

We performed community typing analysis on the sputum microbiome dataset obtained from a healthy Korean twin-family cohort (n = 202) and an external chronic obstructive pulmonary disease (COPD) cohort (n = 324) and implemented a networks analysis to investigate the associations of bacterial metacommunities with host health parameters and microbial interactions in disease.

Results

The analysis of the sputum microbiome of a healthy Korean cohort revealed high levels of interindividual variation, which was driven by two dominant bacteria: Neisseria and Prevotella. Community typing of the cohort samples identified three metacommunities, namely, Neisseria 1 (N1), Neisseria 2 (N2), and Prevotella (P), each of which showed different functional potential and links to host traits (e.g., triglyceride levels, waist circumference, and levels of high-sensitivity C-reactive protein). In particular, the Prevotella-dominant metacommunity showed a low-community diversity, which implies an adverse health association. Network analysis of the healthy twin cohort illustrated co-occurrence of Prevotella with pathogenic anaerobic bacteria; this bacterial cluster was negatively associated with high-density lipoproteins but positively correlated with waist circumference, blood pressure, and pack-years. Community typing of the external COPD cohort identified three sub-metacommunities: one exclusively comprising healthy subjects (HSs) and the other two (CS1 and CS2) comprising patients. The two COPD metacommunities, CS1 and CS2, showed different abundances of specific pathogens, such as Serratia and Moraxella, as well as differing functional potential and community diversity. Network analysis of the COPD cohort showed enhanced bacterial coexclusions in the CS metacommunities when compared with HS metacommunity.

Conclusion

Overall, our findings point to a potential association between pulmonary Prevotella and host health and disease, making it possible to implement community typing for the diagnosis of heterogenic respiratory disease.

The prognosis of pre-frail chronic obstructive pulmonary disease patients for hospitalizations and mortality depends on their level of functional physical performance

Objective

To determine if pre-frail Chronic obstructive pulmonary disease (COPD) patients with poor and non-poor performance in the five-repetition sit-to-stand test (5-STS) had a worse prognosis for hospitalization and mortality at 2 years and for mortality at 5 years than non-frail patients.

Methods

We prospectively included patients with stable COPD, between 40 and 80 years, from a hospital in Spain. Patients were classified according their performance on the 5-STS test and level of frailty. Timing, number of hospitalizations, length of stay, and timing and rate of mortality were outcome measures. Patients were followed for 2 years for exacerbations and for 5 years for mortality. Kaplan-Meier curves and univariate and multivariate Cox proportional-hazard analyses, ANOVA tests and univariate and multivariate linear and logistic regression models were used.

Results

Of the 125 patients included, 25.6% were pre-frail with poor performance, 57% pre-frail with non-poor performance, and 17.4% non-frail with non-poor performance. Pre-frail patients with poor performance had a higher number of hospitalizations (adjusted beta: 0.49; 95% CI: 0.01–0.96), mortality rates (odds ratio: 11.33; 95% CI: 1.15–110.81), and risk at 5 years (adjusted hazard ratio: 8.77; 95% CI: 1.02–75.51) than non-frail patients. Pre-frail patients with poor performance also had worse prognoses than non-frail patients with respect to length of hospital stays (increased by 4.16 days) and timing to first hospitalization (HR: 6.01) in unadjusted models, but not when adjusted.

Conclusion

The COPD prognosis of pre-frail patients with respect to the number of exacerbations with hospitalization and the timing and rate of mortality is dependent of functional performance.

Development and multimodal characterization of an elastase-induced emphysema mouse disease model for the COPD frequent bacterial exacerbator phenotype

Chronic obstructive pulmonary disease (COPD) patients undergo infectious exacerbations whose frequency identifies a clinically meaningful phenotype. Mouse models have been mostly used to separately study both COPD and the infectious processes, but a reliable model of the COPD frequent exacerbator phenotype is still lacking. Accordingly, we first established a model of single bacterial exacerbation by nontypeable Haemophilus influenzae (NTHi) infection on mice with emphysema-like lesions. We characterized this single exacerbation model combining both noninvasive in vivo imaging and ex vivo techniques, obtaining longitudinal information about bacterial load and the extent of the developing lesions and host responses. Bacterial load disappeared 48 hours post-infection (hpi). However, lung recovery, measured using tests of pulmonary function and the disappearance of lung inflammation as revealed by micro-computed X-ray tomography, was delayed until 3 weeks post-infection (wpi). Then, to emulate the frequent exacerbator phenotype, we performed two recurrent episodes of NTHi infection on the emphysematous murine lung. Consistent with the amplified infectious insult, bacterial load reduction was now observed 96 hpi, and lung function recovery and disappearance of lesions on anatomical lung images did not happen until 12 wpi. Finally, as a proof of principle of the use of the model, we showed that azithromycin successfully cleared the recurrent infection, confirming this macrolide utility to ameliorate infectious exacerbation. In conclusion, we present a mouse model of recurrent bacterial infection of the emphysematous lung, aimed to facilitate investigating the COPD frequent exacerbator phenotype by providing complementary, dynamic information of both infectious and inflammatory processes.

Anti-Inflammatory Function of Fatty Acids and Involvement of Their Metabolites in the Resolution of Inflammation in Chronic Obstructive Pulmonary Disease

Lipid metabolism plays an important role in many lung functions. Disorders of lipid metabolism are part of the pathogenesis of chronic obstructive pulmonary disease (COPD). Lipids are involved in numerous cross-linkages with inflammation. Recent studies strongly support the involvement of fatty acids as participants in inflammation. They are involved in the initiation and resolution of inflammation, including acting as a substrate for the formation of lipid mediators of inflammation resolution. Specialized pro-inflammatory mediators (SPMs) belonging to the classes of lipoxins, resolvins, maresins, and protectins, which are formed enzymatically from unsaturated fatty acids, are now described. Disorders of their production and function are part of the pathogenesis of COPD. SPMs are currently the subject of active research in order to find new drugs. Short-chain fatty acids are another important participant in metabolic and immune processes, and their role in the pathogenesis of COPD is of great clinical interest.

Frailty and chronic respiratory disease: the need for a multidisciplinary care model

Background.

Frailty is a state of increased vulnerability to various health stressors but little information is summarized about frailty in patients with specific chronic respiratory diseases such as chronic obstructive pulmonary disease (COPD), idiopathic pulmonary fibrosis (IPF), and asthma.

Objective.

We aimed to describe the burden of frailty on patients with chronic respiratory disorders and to discuss the need for multidisciplinary care services.

Methods.

PubMed and Cochrane Central databases were systematically reviewed for studies reporting outcomes associated with frailty in COPD, IPF, and asthma. Electronic databases were searched for relevant articles published in English from 2010 up to July 2020. Appraisal was carried out based on the Hierarchy of Evidence Rating System and the GRADE guidelines.

Results.

A total of 31 articles met all inclusion criteria with 24 of them at level IV, 1 at level V, and 6 at level VI. Frailty is likely to negatively affect quality of life and to increase the risk of mortality, especially in elderly with COPD, IPF and asthma. Each disease has a particular effect on the balance between health status, respiratory impairment and frailty. A greater understanding of frailty phenotype across different ages, as well as in a range of long-term conditions, is of great necessity in both clinical and research settings. Limited conformity was observed between different methodologies and nature of chronic diseases studied, leading to a further difficulty to extract homogeneous information.

Conclusion.

Literature shows that frailty is prevalent in COPD, IPF, and asthma, after adjusting for shared risk factors. Our findings suggest that frailty should be approached as an entity per se’, in order to assess real mortality risk, alongside respiratory disease severity and the presence of comorbidities. Health care professionals need knowledge, skills and multidisciplinary collaboration to buffer the impact of frailty on everyday practice.

Lipid Metabolism Disorders in the Comorbid Course of Nonalcoholic Fatty Liver Disease and Chronic Obstructive Pulmonary Disease

Non-alcoholic fatty liver disease (NAFLD) is currently among the most common liver diseases. Unfavorable data on the epidemiology of metabolic syndrome and obesity have increased the attention of clinicians and researchers to the problem of NAFLD. The research results allow us to emphasize the systemicity and multifactoriality of the pathogenesis of liver parenchyma lesion. At the same time, many aspects of its classification, etiology, and pathogenesis remain controversial. Local and systemic metabolic disorders are also a part of the pathogenesis of chronic obstructive pulmonary disease and can influence its course. The present article analyzes the metabolic pathways mediating the links of impaired lipid metabolism in NAFLD and chronic obstructive pulmonary disease (COPD). Free fatty acids, cholesterol, and ceramides are involved in key metabolic and inflammatory pathways underlying the pathogenesis of both diseases. Moreover, inflammation and lipid metabolism demonstrate close links in the comorbid course of NAFLD and COPD.

Computed tomography-identified phenotypes of small airway obstructions in chronic obstructive pulmonary disease

ABSTRACT

Chronic obstructive pulmonary disease (COPD) is a heterogeneous disease characteristic of small airway inflammation, obstruction, and emphysema. It is well known that spirometry alone cannot differentiate each separate component. Computed tomography (CT) is widely used to determine the extent of emphysema and small airway involvement in COPD. Compared with the pulmonary function test, small airway CT phenotypes can accurately reflect disease severity in patients with COPD, which is conducive to improving the prognosis of this disease. CT measurement of central airway morphology has been applied in clinical, epidemiologic, and genetic investigations as an inference of the presence and severity of small airway disease. This review will focus on presenting the current knowledge and methodologies in chest CT that aid in identifying discrete COPD phenotypes.

Genetic Evidence on the Association of Interleukin (IL)-1-Mediated Chronic Inflammation with Airflow Obstruction: A Mendelian Randomization Study

Preclinical studies suggest interleukin (IL)-1α/β is involved in the pathogenesis of chronic obstructive pulmonary disease (COPD). However, recent trials of anti-IL-1 therapies showed limited benefit for COPD. To clarify, we primarily examined total and direct effects of IL-1 and its receptors/coreceptors/receptor antagonists (IL-1/IL-1Rs) on airflow obstruction (AO) using Mendelian randomization (MR), and secondarily explored reverse causation using bidirectional MR. We selected independent cis protein quantitative trait loci (cis-pQTLs) as genetic instruments for IL-1/IL-1Rs from two proteomic genome-wide association studies (n = 11,594) of European ancestry (mean age ∼47 years). We applied those cis-pQTLs to the International COPD Genetics Consortium (n = 15,256 cases, 47,936 controls) of ∼81.9% European descent (∼57 years). No IL-1/IL-1Rs were significantly associated with AO after correction for multiple testing. However, a higher genetically predicted IL-1 receptor antagonist (IL-1Ra) was nominally associated with a 20% reduction in AO risk using univariable MR, with a larger direct effect (∼31%, i.e. not via IL-1α/β) using multivariable MR. Furthermore, higher total IL-18 binding protein (IL-18BP) was nominally associated with lower AO. Nominal total effects were also noted for higher IL-1α with lower AO and higher IL-1R1 with higher AO. Higher IL-1Ra and IL-18BP might have a role in preventing AO, but need to be contextualized.Supplemental data for this article is available online at https://doi.org/10.1080/15412555.2021.1955848 .

Molecular Mechanisms of Lipid Metabolism Disorders in Infectious Exacerbations of Chronic Obstructive Pulmonary Disease

Exacerbations largely determine the character of the progression and prognosis of chronic obstructive pulmonary disease (COPD). Exacerbations are connected with changes in the microbiological landscape in the bronchi due to a violation of their immune homeostasis. Many metabolic and immune processes involved in COPD progression are associated with bacterial colonization of the bronchi. The objective of this review is the analysis of the molecular mechanisms of lipid metabolism and immune response disorders in the lungs in COPD exacerbations. The complex role of lipid metabolism disorders in the pathogenesis of some infections is only beginning to be understood, however, there are already fewer and fewer doubts even now about its significance both in the pathogenesis of infectious exacerbations of COPD and in general in the progression of the disease. It is shown that the lipid rafts of the plasma membranes of cells are involved in many processes related to the detection of pathogens, signal transduction, the penetration of pathogens into the cell. Smoking disrupts the normally proceeded processes of lipid metabolism in the lungs, which is a part of the COPD pathogenesis.

Chronic Obstructive Pulmonary Disease: Epidemiology, Biomarkers, and Paving the Way to Lung Cancer

Chronic obstructive pulmonary disease (COPD), the frequently fatal pathology of the respiratory tract, accounts for half a billion cases globally. COPD manifests via chronic inflammatory response to irritants, frequently to tobacco smoke. The progression of COPD from early onset to advanced disease leads to the loss of the alveolar wall, pulmonary hypertension, and fibrosis of the respiratory epithelium. Here, we focus on the epidemiology, progression, and biomarkers of COPD with a particular connection to lung cancer. Dissecting the cellular and molecular players in the progression of the disease, we aim to shed light on the role of smoking, which is responsible for the disease, or at least for the more severe symptoms and worse patient outcomes. We summarize the inflammatory conditions, as well as the role of EMT and fibroblasts in establishing a cancer-prone microenvironment, i.e., the soil for ‘COPD-derived’ lung cancer. We highlight that the major health problem of COPD can be alleviated via smoking cessation, early diagnosis, and abandonment of the usage of biomass fuels on a global basis.

Novel Thoracic MRI Approaches for the Assessment of Pulmonary Physiology and Inflammation

Excessive pulmonary inflammation can lead to damage of lung tissue, airway remodelling and established structural lung disease. Novel therapeutics that specifically target inflammatory pathways are becoming increasingly common in clinical practice, but there is yet to be a similar stepwise change in pulmonary diagnostic tools. A variety of thoracic magnetic resonance imaging (MRI) tools are currently in development, which may soon fulfil this emerging clinical need for highly sensitive assessments of lung structure and function. Given conventional MRI techniques are poorly suited to lung imaging, alternate strategies have been developed, including the use of inhaled contrast agents, intravenous contrast and specialized lung MR sequences. In this chapter, we discuss technical challenges of performing MRI of the lungs and how they may be overcome. Key thoracic MRI modalities are reviewed, namely, hyperpolarized noble gas MRI, oxygen-enhanced MRI (OE-MRI), ultrashort echo time (UTE) MRI and dynamic contrast-enhanced (DCE) MRI. Finally, we consider potential clinical applications of these techniques including phenotyping of lung disease, evaluation of novel pulmonary therapeutic efficacy and longitudinal assessment of specific patient groups.

Pulmonary function testing in COPD: looking beyond the curtain of FEV1

Chronic obstructive pulmonary disease (COPD) management remains challenging due to the high heterogeneity of clinical symptoms and the complex pathophysiological basis of the disease. Airflow limitation, diagnosed by spirometry, remains the cornerstone of the diagnosis. However, the calculation of the forced expiratory volume in the first second (FEV1) alone, has limitations in uncovering the underlying complexity of the disease. Incorporating additional pulmonary function tests (PFTs) in the everyday clinical evaluation of COPD patients, like resting volume, capacity and airway resistance measurements, diffusion capacity measurements, forced oscillation technique, field and cardiopulmonary exercise testing and muscle strength evaluation, may prove essential in tailoring medical management to meet the needs of such a heterogeneous patient population. We aimed to provide a comprehensive overview of the available PFTs, which can be incorporated into the primary care physician's practice to enhance the efficiency of COPD management.

Imbalance Between Injury and Defense in the COPD Emphysematous Phenotype

The chronic obstructive pulmonary disease (COPD) emphysematous phenotype is characterized by destruction of lung tissue structure. Patients with this phenotype usually present with typical emphysema-like changes on chest computed Tomography CT, experience higher mortality and poorer prognosis, and are insensitive to routine pharmacological COPD therapy. However, the pathogenesis for the COPD emphysematous phenotype remains unclear, resulting in diagnostic and therapeutic challenges. The imbalance between injury and defense mechanisms is essential in the progression of many pulmonary diseases. Thus, in this review, we focus on the pathogenesis of the COPD emphysematous phenotype and discuss the pathophysiological processes involved in disease progression, from the perspective of injury and defense imbalance.

Impact of Frailty on the Risk of Exacerbations and All-Cause Mortality in Elderly Patients with Stable Chronic Obstructive Pulmonary Disease

Rationale

For the high prevalence of frail in patients with chronic obstructive pulmonary disease (COPD), further study should explore an in-depth understanding of the relationship between frailty and prognosis of COPD.

Objective

To determine the correlation between frailty and risk of acute exacerbation, hospitalizations, and mortality in older patients with stable COPD.

Participants and Methods

Consecutive older adults (≥65) diagnosed with stable COPD from January 2018 to July 2019, with an average follow-up of 546 days (N = 309). Frailty was defined by the Fried frailty phenotype. Poisson regression was performed to assess the influence of frailty on the incidence of acute exacerbations of COPD (AECOPD) and all-cause hospitalizations in a year. Cox regression was performed to evaluate the effect of frailty on all-cause mortality in patients with stable COPD.

Results

The prevalence of frailty was 49.8%. The most common phenotypic characteristics were weakness (99.4%) followed by slowness (92.9%). After adjustment, frailty increased the incidence of AECOPD (IRR = 1.75, 95% CI: 1.09–2.82) and all-cause hospitalizations (IRR = 1.39, 95% CI 1.04–1.87) within a year. Slowness was associated with AECOPD (IRR = 1.77, 95% CI: 1.03–3.03), and weakness was associated with increased all-cause hospitalizations (IRR = 1.53, 95% CI: 1.04–2.25). The all-cause mortality risk was more than twofold higher in frail patients (HR = 2.54, 95% CI: 1.01–6.36) than non-frail patients. Low physical activity (HR = 2.66, 95% CI: 1.17–6.05) and weight loss (HR = 2.15, 95% CI: 1.02–4.51) were significantly associated with increased all-cause mortality in patients with COPD.

Conclusion

Frailty increased the incidence of acute exacerbation and hospitalization, as well as increased mortality in older patients with stable COPD. This knowledge will help physicians identify high-risk groups with COPD and frailty who may benefit from targeted interventions to prevent disease progression.

Effect of TRPM8 and TRPA1 Polymorphisms on COPD Predisposition and Lung Function in COPD Patients

Certain transient receptor potential (TRP) channels including TRPM8 and TRPA1 are widely expressed in the respiratory tract and have been shown to be the receptors of cigarette smoke and particulate matter-the main causative factors of chronic obstructive pulmonary disease (COPD). The aim of the study was to investigate the effect of TRPM8 and TRPA1 polymorphisms on COPD predisposition and lung function in COPD patients. The study enrolled 143 COPD patients and 104 smokers with post-bronchodilator forced expiratory volume in one second (FEV1)/forced vital capacity (FVC) > 70%. Lung function was measured by spirometry. TRPM8 and TRPA1 polymorphisms were genotyped by LATE-PCR. None of the polymorphisms significantly influenced COPD predisposition after correction for covariates and multiple testing. Among COPD patients, the TT genotype of TRPA1 rs7819749 was significantly associated with higher degree of bronchial obstruction. In addition, we established that carriers of the C allele of TRPM8 rs11562975 more commonly had post-bronchodilator FEV1 < 60% (OR 3.2, 95%CI (1.14-8.94), p = 0.03) and revealed the effect of TRPA1 rs959976 and TRPM8 rs17865682 on bronchodilator response in COPD. Thus, the obtained results suggest possible involvement of TRPM8 and TRPA1 in COPD pathogenesis, indicating the necessity to further investigate their functional role in this pathology.

Chronic obstructive pulmonary disease - diagnosis and management of stable disease; a personalized approach to care, using the treatable traits concept based on clinical phenotypes. Position paper of the Czech Pneumological and Phthisiological Society

This position paper has been drafted by experts from the Czech national board of diseases with bronchial obstruction, of the Czech Pneumological and Phthisiological Society. The statements and recommendations are based on both the results of randomized controlled trials and data from cross-sectional and prospective real-life studies to ensure they are as close as possible to the context of daily clinical practice and the current health care system of the Czech Republic. Chronic Obstructive Pulmonary Disease (COPD) is a preventable and treatable heterogeneous syndrome with a number of pulmonary and extrapulmonary clinical features and concomitant chronic diseases. The disease is associated with significant mortality, morbidity and reduced quality of life. The main characteristics include persistent respiratory symptoms and only partially reversible airflow obstruction developing due to an abnormal inflammatory response of the lungs to noxious particles and gases. Oxidative stress, protease-antiprotease imbalance and increased numbers of pro-inflammatory cells (mainly neutrophils) are the main drivers of primarily non-infectious inflammation in COPD. Besides smoking, household air pollution, occupational exposure, low birth weight, frequent respiratory infections during childhood and also genetic factors are important risk factors of COPD development. Progressive airflow limitation and airway remodelling leads to air trapping, static and dynamic hyperinflation, gas exchange abnormalities and decreased exercise capacity. Various features of the disease are expressed unequally in individual patients, resulting in various types of disease presentation, emerging as the "clinical phenotypes" (for specific clinical characteristics) and "treatable traits" (for treatable characteristics) concept. The estimated prevalence of COPD in Czechia is around 6.7% with 3,200-3,500 deaths reported annually. The elementary requirements for diagnosis of COPD are spirometric confirmation of post-bronchodilator airflow obstruction (post-BD FEV₁/VCmax <70%) and respiratory symptoms assessement (dyspnoea, exercise limitation, cough and/or sputum production. In order to establish definite COPD diagnosis, a five-step evaluation should be performed, including: 1/ inhalation risk assessment, 2/ symptoms evaluation, 3/ lung function tests, 4/ laboratory tests and 5/ imaging. At the same time, all alternative diagnoses should be excluded. For disease classification, this position paper uses both GOLD stages (1 to 4), GOLD groups (A to D) and evaluation of clinical phenotype(s). Prognosis assessment should be done in each patient. For this purpose, we recommend the use of the BODE or the CADOT index. Six elementary clinical phenotypes are recognized, including chronic bronchitis, frequent exacerbator, emphysematous, asthma/COPD overlap (ACO), bronchiectases with COPD overlap (BCO) and pulmonary cachexia. In our concept, all of these clinical phenotypes are also considered independent treatable traits. For each treatable trait, specific pharmacological and non-pharmacological therapies are defined in this document. The coincidence of two or more clinical phenotypes (i.e., treatable traits) may occur in a single individual, giving the opportunity of fully individualized, phenotype-specific treatment. Treatment of COPD should reflect the complexity and heterogeneity of the disease and be tailored to individual patients. Major goals of COPD treatment are symptom reduction and decreased exacerbation risk. Treatment strategy is divided into five strata: risk elimination, basic treatment, phenotype-specific treatment, treatment of respiratory failure and palliative care, and treatment of comorbidities. Risk elimination includes interventions against tobacco smoking and environmental/occupational exposures. Basic treatment is based on bronchodilator therapy, pulmonary rehabilitation, vaccination, care for appropriate nutrition, inhalation training, education and psychosocial support. Adequate phenotype-specific treatment varies phenotype by phenotype, including more than ten different pharmacological and non-pharmacological strategies. If more than one clinical phenotype is present, treatment strategy should follow the expression of each phenotypic label separately. In such patients, multicomponental therapeutic regimens are needed, resulting in fully individualized care. In the future, stronger measures against smoking, improvements in occupational and environmental health, early diagnosis strategies, as well as biomarker identification for patients responsive to specific treatments are warranted. New classes of treatment (inhaled PDE3/4 inhibitors, single molecule dual bronchodilators, anti-inflammatory drugs, gene editing molecules or new bronchoscopic procedures) are expected to enter the clinical practice in a very few years.

Adherence to Global Initiative for Chronic Obstructive Lung Disease guidelines in the real world: current understanding, barriers, and solutions

PURPOSE OF REVIEW

The Global Initiative for Chronic Obstructive Lung Disease (GOLD) provides a comprehensive review and guidance for clinicians managing patients with chronic obstructive pulmonary disease (COPD). However, adherence to GOLD guidelines has been suboptimal over the years. The current review summarizes the current body of literature addressing the multitude of reasons for the lack of adherence to GOLD guidelines in clinical practice.

RECENT FINDINGS

There continue to be several reasons for suboptimal adoption of GOLD guidelines in clinical practice. A primary and recurrent theme appears to be both delayed as well as missed diagnosis of COPD. There are several reasons for this including lack of awareness about current COPD guidelines, lack of availability as well as utilization of office spirometry and improper symptom assessment. Other issues include improper selection of proper pharmacotherapy options, misdiagnosis/mislabeling of COPD phenotypes, lack of smoking cessation counselling as well as enrollment in pulmonary rehabilitation. Potential solutions include adoption of clinical decision support systems, self-care models and careful phenotyping of COPD patients.

SUMMARY

There are currently several barriers for the adoption of GOLD guidelines into routine clinical practice. These barriers are all amenable to systematic solutions that will increase adherence to current GOLD guidelines.

QSAR without borders

Prediction of chemical bioactivity and physical properties has been one of the most important applications of statistical and more recently, machine learning and artificial intelligence methods in chemical sciences. This field of research, broadly known as quantitative structure-activity relationships (QSAR) modeling, has developed many important algorithms and has found a broad range of applications in physical organic and medicinal chemistry in the past 55+ years. This Perspective summarizes recent technological advances in QSAR modeling but it also highlights the applicability of algorithms, modeling methods, and validation practices developed in QSAR to a wide range of research areas outside of traditional QSAR boundaries including synthesis planning, nanotechnology, materials science, biomaterials, and clinical informatics. As modern research methods generate rapidly increasing amounts of data, the knowledge of robust data-driven modelling methods professed within the QSAR field can become essential for scientists working both within and outside of chemical research. We hope that this contribution highlighting the generalizable components of QSAR modeling will serve to address this challenge.

Frequency of Blood Eosinophilia in newly diagnosed Chronic Obstructive Pulmonary Disease patients

OBJECTIVE

To determine Blood Eosinophilia frequency in newly diagnosed Chronic Obstructive Pulmonary Disease patients.

METHODS

An observational cross-sectional research on newly diagnosed COPD patients with age ≥ 40 years was performed at Ojha Institute of Chest Diseases, Dow University of Health Sciences Karachi. COPD patients diagnosed in outpatient clinic or admitted in Chest Unit during six-month period from September 2018 to May 2019 were selected. Each patient underwent spirometry, and blood was tested for eosinophilia (≥ 2% eosinophils in blood), after obtaining informed consent and clinical history.

RESULTS

One hundred and fifty COPD patients were diagnosed and evaluated for Blood Eosinophilia, out of which 86 (57.3%) and 64 (42.7%) patients were Males and Females respectively with mean age of 63.72 ± 10.24 years. Current Smokers were 48 (32.0%), Ex-Smokers 15 (10.0%), and Biomass Exposure was present in 76 (50.7%) of patients. Spirometric severity of COPD was Mild in 11 (7.3%), Moderate in 68 (45.3%), Severe in 59 (39.3%), and Very Severe in 12 (8.0%) patients. Blood Eosinophilia was present in 59 (39.3%) patients of COPD among which majority 43 (72.9%) were having Moderate 24 (40.7%) and Severe 19 (32.2%) COPD respectively.

CONCLUSION

Frequency of Blood Eosinophilia in newly diagnosed COPD patients was high, among which most of the COPD patients were moderate to severe.

CYP1B1, VEGFA, BCL2, and CDKN1A Affect the Development of Chronic Obstructive Pulmonary Disease

Purpose

Chronic obstructive pulmonary disease (COPD) is a progressive lung disease characterized by poor airflow. The purpose of this study was to explore the mechanisms involved in the development of COPD.

Patients and Methods

The mRNA expression profile GSE100281, consisting of 79 COPD and 16 healthy samples, was acquired from the Gene Expression Omnibus database. The differentially expressed genes (DEGs) between COPD samples and healthy samples were analyzed using the limma package. Functional enrichment analysis for the DEGs was carried out using the Database for Annotation, Visualization, and Integrated Discovery (DAVID) tool. Furthermore, DEG-compound pairs were predicted using the Comparative Toxicogenomics Database. The KEGG metabolite IDs corresponding to the compounds were also obtained through the MetaboAnalyst pipeline. Based on the diffusion algorithm, the metabolite network was constructed. Finally, the expression levels of key genes were determined using quantitative PCR (qPCR).

Results

There were 594 DEGs identified between the COPD and healthy samples, including 242 upregulated and 352 downregulated genes. A total of 696 DEG-compound pairs, such as BCL2-C00469 (ethanol) and BCL2-C00389 (quercetin) pairs, were predicted. CYP1B1, VEGFA, BCL2, and CDKN1A were included in the top 10 DEG-compound pairs. Additionally, 57 metabolites were obtained. In particular, hsa04750 (inflammatory mediator regulation of TRP channels)-C00469 (ethanol) and hsa04152 (AMPK signaling pathway)-C00389 (quercetin) pairs were found in the metabolite network. The results of qPCR showed that the expression of CYP1B1, VEGFA, BCL2, and CDKN1A was consistent with that predicted using bioinformatic analysis.

Conclusion

CYP1B1, VEGFA, BCL2, and CDKN1A may play important functions in the development and progression of COPD.

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.

Blood eosinophils as biomarkers of therapeutic response to chronic obstructive pulmonary disease: Still work in progress

Disease phenotyping is a key step towards an increasingly personalized approach to chronic obstructive pulmonary disease (COPD), leading to a more precise assessment, treatment and definition of disease outcomes. The search for biomarkers able to guide the identification of COPD phenotypes are of great importance for both researchers and clinicians. However, while several biomarkers of inflammation [e.g., peripheral blood eosinophils and fractional expired nitric oxide] have been identified and applied in asthma, none has been successfully linked to discrete clinical parameters of COPD such as exacerbations, natural progression, and treatment response or mortality risk. Recently, several studies have shown that blood eosinophils are a potential biomarker for patient subset stratification in COPD therapy. Here we reviewed the value of blood eosinophils in predicting the response of COPD patients to treatment.

Phenotypes of osteoarthritis: current state and future implications

In the most recent years, an extraordinary research effort has emerged to disentangle osteoarthritis heterogeneity, opening new avenues for progressing with therapeutic development and unravelling the pathogenesis of this complex condition. Several phenotypes and endotypes have been proposed albeit none has been sufficiently validated for clinical or research use as yet. This review discusses the latest advances in OA phenotyping including how new modern statistical strategies based on machine learning and big data can help advance this field of research.

Chronic obstructive pulmonary disease classification, phenotypes and risk assessment

Chronic obstructive pulmonary disease (COPD) is a heterogeneous disease. Various classification systems and phenotypes have been proposed. This review highlights the current classifications of COPD, describes the major phenotypes and provides a blue print for risk assessment of COPD. It is likely that more phenotypes and endotypes of COPD will be described paving the way to personalized medicine for patients with COPD.

Prediction of first acute exacerbation using COPD subtypes identified by cluster analysis

Purpose

In patients with COPD, acute exacerbation (AE) is not only an important determinant of prognosis, but also an important factor in choosing therapeutic agents. In this study, we evaluated the usefulness of COPD subtypes identified through cluster analysis to predict the first AE.

Patients and methods

Among COPD patients in the Korea COPD Subgroup Study (KOCOSS) cohort, 1,195 who had follow-up data for AE were included in our study. We selected seven variables for cluster analysis – age, body mass index, smoking status, history of asthma, COPD assessment test (CAT) score, post-bronchodilator (BD) FEV₁ % predicted, and diffusing capacity of carbon monoxide % predicted.

Results

K-means clustering identified four clusters for COPD that we named putative asthma-COPD overlap (ACO), mild COPD, moderate COPD, and severe COPD subtypes. The ACO group (n=196) showed the second-best post-BD FEV₁ (75.5% vs 80.9% [mild COPD, n=313] vs 52.4% [moderate COPD, n=345] vs 46.7% [severe COPD, n=341] predicted), the longest 6-min walking distance (424 m vs 405 m vs 389  m vs 365 m), and the lowest CAT score (12.2 vs 13.7 vs 15.6 vs 17.5) among the four groups. ACO group had greater risk for first AE compared to the mild COPD group (HR, 1.683; 95% CI, 1.175–2.410). The moderate COPD and severe COPD group HR values were 1.587 (95% CI, 1.145–2.200) and 1.664 (95% CI, 1.203–2.302), respectively. In addition, St. George’s Respiratory Questionnaire score (HR: 1.019; 95% CI, 1.014–1.024) and gastroesophageal reflux disease were independent factors associated with the first AE (HR: 1.535; 95% CI, 1.116–2.112).

Conclusion

Our cluster analysis revealed an exacerbator subtype of COPD independent of FEV₁. Since these patients are susceptible to AE, a more aggressive treatment strategy is needed in these patients.

Patient-Reported Consequences of Community-Acquired Pneumonia in Patients with Chronic Obstructive Pulmonary Disease

Community acquired pneumonia (CAP) carries high morbidity, mortality, and economic burden, which is even higher in adults diagnosed with chronic obstructive pulmonary disease (COPD). While several studies have assessed the clinical burden and mortality risk of CAP and COPD, very few studies focus on CAP burden from a COPD patient perspective. Individuals recently diagnosed with CAP and with pre-existing COPD were recruited through the COPD Foundation. The CAP Burden of Illness Questionnaire (CAP-BIQ), a content validated questionnaire assessing CAP symptomatology, duration of symptoms and CAP impact on work, activities and family, was administered at baseline and at 30-days follow-up. Of the 490 participants recruited, 481 had data sufficient for analysis. The prevalence of respiratory-related symptoms was very high (>90%) at the time of diagnosis with other generalized symptoms such as fatigue, trouble sleeping, headaches and confusion present in more than 60% of participants. Mean duration of symptoms varied from approximately 2 weeks for headaches and fever to more than a month for fatigue, wheezing, dyspnea, and cough. Employed participants missed an average of 21 days of work and those not employed missed 36 days of usual activities. Over 84% required help from family, friends or care givers. CAP is a serious and burdensome condition for people with COPD, a condition that can impair activities for weeks, frequently requires care from family or friends, and includes lingering symptoms. The patient-reported impact of CAP reported in this study underscores the need for prevention strategies in this population.

Adjuvant therapy efficacy of Chinese drugs pharmaceutics for COPD patients with respiratory failure: a meta-analysis

We performed a meta-analysis to evaluate the efficacy and safety of Western medicine combined with Tanreqing for patients with chronic obstructive pulmonary disease (COPD) and respiratory failure. We comprehensively searched several online databases from the times of their inception to November 2018. The trial quality was assessed using the bias risk tool recommended by the Cochrane library. Relative risks (RRs) and their 95% confidence intervals (CIs) for binary outcomes and weighted mean differences (MDs) with 95% CIs for continuous data were calculated. A fixed effect model indicated that integrated Tanreqing group experienced higher overall treatment effectiveness (RR = 1.23, 95% CI: 1.17–1.30, P=0.000). Pooled results from random effects models indicated the oxygen partial pressure of the test group was significantly higher than that of the control groups (MD = 9.55, 95% CI: 4.57–14.52, P<0.000). The carbon dioxide pressure of the test group was significantly lower than that of the control groups (MD = –6.06, 95% CI: –8.19 to –3.93, P=0.000). The lung function score of the test group was significantly higher than that of the control group (MD = 7.87, 95% CI: 4.45–11.29). Sensitivity analysis indicated that the data were statistically robust. Clinical effects of Western medicine combined with Tanreqing used to treat combined COPD/respiratory failure were better than those afforded by Western medicine; no serious adverse reactions were noted. However, publication bias was evident, and further trials with larger sample sizes are required.

Comparing biologicals and small molecule drug therapies for chronic respiratory diseases: An EAACI Taskforce on Immunopharmacology position paper

Chronic airway diseases such as asthma and chronic obstructive pulmonary disease (COPD), together with their comorbidities, bear a significant burden on public health. Increased appreciation of molecular networks underlying inflammatory airway disease needs to be translated into new therapies for distinct phenotypes not controlled by current treatment regimens. On the other hand, development of new safe and effective therapies for such respiratory diseases is an arduous and expensive process. Antibody-based (biological) therapies are successful in treating certain respiratory conditions not controlled by standard therapies such as severe allergic and refractory eosinophilic severe asthma, while in other inflammatory respiratory diseases, such as COPD, biologicals are having a more limited impact. Small molecule drug (SMD)-based therapies represent an active field in pharmaceutical research and development. SMDs expand biologicals' therapeutic targets by reaching the intracellular compartment by delivery as either an oral or topically based formulation, offering both convenience and lower costs. Aim of this review was to compare and contrast the distinct pharmacological properties and clinical applications of SMDs- and antibody-based treatment strategies, their limitations and challenges, in order to highlight how they should be integrated for their optimal utilization and to fill the critical gaps in current treatment for these chronic inflammatory respiratory diseases.

The Impact of Sepsis on the Outcomes of COPD Patients: A Population-Based Cohort Study

This study aims to identify the impact of new-onset sepsis in patients with chronic obstructive pulmonary disease (COPD) including the effects on acute exacerbations, pneumonia and mortality. Using the National Health Insurance Research Database of Taiwan, all patients with COPD older than 40 years between 1988 and 2010 were recruited. After propensity score matching, each of the 8774 COPD patients with and without sepsis were identified to have similar characteristics. The primary outcome was severe exacerbations of COPD, with a severe exacerbation being defined as a patient requiring hospital admission or an emergency department visit due to COPD. The secondary outcomes were pneumonia, serious pneumonia, and all-cause mortality. The post-index overall cumulative incidence rates of total acute exacerbations were 11.2/person-years in the sepsis group and 6.2/person-years in the non-sepsis group (adjusted hazard ratio (HR) = 1.38, 95% confidence interval (CI), 1.38⁻1.40). The sepsis group also had higher risks of severe exacerbations (adjusted HR = 2.05, 95% CI, 2.02⁻2.08), severe exacerbations requiring hospitalization (adjusted HR = 2.30, 95% CI, 2.24⁻2.36), and severe exacerbations leading to an emergency room visit (adjusted HR = 1.91, 95% CI, 1.87⁻1.94). Regarding the effect on secondary outcomes, the sepsis group had higher risks of mortality (incidence rate: 23.7/person-years vs. 11.34/person-years, adjusted HR = 2.27, 95% CI, 2.14⁻2.41), pneumonia (incidence rate: 26.41 per person-days vs. 10.34 per person-days, adjusted HR = 2.70, 95% CI, 2.5⁻2.91), and serious pneumonia (incidence rate: 5.84 per person-days vs. 1.98 per person-days, adjusted HR = 2.89, 95% CI, 2.5⁻3.33) compared with the non-sepsis group. Sepsis survivors among patients with COPD had a higher risk of severe exacerbations, pneumonia, serious pneumonia, and mortality compared to patients with COPD without sepsis.

Inspiratory pre-motor potentials during quiet breathing in ageing and chronic obstructive pulmonary disease

KEY POINTS

A cortical contribution to breathing, as indicated by a Bereitschaftspotential (BP) in averaged electroencephalographic signals, occurs in healthy individuals when external inspiratory loads are applied. Chronic obstructive pulmonary disease (COPD) is a condition where changes in the lung, chest wall and respiratory muscles produce an internal inspiratory load. These changes also occur in normal ageing, although to a lesser extent. In the present study, we determined whether BPs are present during quiet breathing and breathing with an external inspiratory load in COPD compared to age-matched and young healthy controls. We demonstrated that increased age, rather than COPD, is associated with a cortical contribution to quiet breathing. A cortical contribution to inspiratory loading is associated with more severe dyspnoea (i.e. the sensation of breathlessness). We propose that cortical mechanisms may be engaged to defend ventilation in ageing with dyspnoea as a consequence.

ABSTRACT

A cortical contribution to breathing is determined by the presence of a Bereitschaftspotential, a low amplitude negativity in the averaged electroencephalographic (EEG) signal, which begins ∼1 s before inspiration. It occurs in healthy individuals when external inspiratory loads to breathing are applied. In chronic obstructive pulmonary disease (COPD), changes in the lung, chest wall and respiratory muscles produce an internal inspiratory load. We hypothesized that there would be a cortical contribution to quiet breathing in COPD and that a cortical contribution to breathing with an inspiratory load would be linked to dyspnoea, a major symptom of COPD. EEG activity was analysed in 14 participants with COPD (aged 57-84 years), 16 healthy age-matched (57-87 years) and 15 young (18-26 years) controls during quiet breathing and inspiratory loading. The presence of Bereitschaftspotentials, from ensemble averages of EEG epochs at Cz and FCz, were assessed by blinded assessors. Dyspnoea was rated using the Borg scale. The incidence of a cortical contribution to quiet breathing was significantly greater in participants with COPD (6/14) compared to the young (0/15) (P = 0.004) but not the age-matched controls (6/16) (P = 0.765). A cortical contribution to inspiratory loading was associated with higher Borg ratings (P = 0.007), with no effect of group (P = 0.242). The data show that increased age, rather than COPD, is associated with a cortical contribution to quiet breathing. A cortical contribution to inspiratory loading is associated with more severe dyspnoea. We propose that cortical mechanisms may be engaged to defend ventilation with dyspnoea as a consequence.

COPD stands for complex obstructive pulmonary disease

Chronic obstructive pulmonary disease (COPD) has extensively been reported as a complex disease affecting patients' health beyond the lungs with a variety of intra- and extrapulmonary components and considerable variability between individuals. This review discusses the assessment of this complexity and underlines the importance of transdisciplinary management programmes addressing the physical, emotional and social health of the individual patient.COPD management is challenging and requires advanced, sophisticated strategies meeting the patient's individual needs. Due to the heterogeneity and complexity of the disease leading to non-linear and consequently poorly predictable treatment responses, multidimensional patient profiling is crucial to identify the right COPD patient for the right treatment. Current methods are often restricted to general, well-known and commonly used assessments neglecting potentially relevant (interactions between) individual, unique "traits" to finally ensure personalised treatment. Dynamic, personalised and holistic approaches are needed to tackle this multifaceted disease and to ensure personalised medicine and value-based healthcare.