Mechanisms and impact of the frequent exacerbator phenotype in chronic obstructive pulmonary disease

Clinical Characteristics and Frequency of Chronic Obstructive Pulmonary Disease Exacerbations in Korean Patients: Findings From the KOCOSS Cohort 2012-2021

BACKGROUND

Acute exacerbations of chronic obstructive pulmonary disease (AECOPD) exert a substantial burden on patients and healthcare systems; however, data related to the frequency of AECOPD in the Korean population are limited. Therefore, this study aimed to describe the frequency of severe, and moderate or severe AECOPD, as well as clinical and demographic characteristics of patients with chronic obstructive pulmonary disease (COPD) in South Korea.

METHODS

Data from patients aged > 40 years with post-bronchodilator forced expiratory volume in 1 second (FEV1)/forced vital capacity ≤ 70% of the normal predicted value from the Korea COPD Subgroup Study database were analyzed (April 2012 to 2021). The protocol was based on the EXAcerbations of COPD and their OutcomeS International study. Data were collected retrospectively for year 0 (0-12 months before study enrollment) based on patient recall, and prospectively during years 1, 2, and 3 (0-12, 13-24, and 25-36 months after study enrollment, respectively). The data were summarized using descriptive statistics.

RESULTS

Data from 3,477 Korean patients (mean age, 68.5 years) with COPD were analyzed. Overall, most patients were male (92.3%), former or current smokers (90.8%), had a modified Medical Research Council dyspnea scale score ≥ 1 (83.3%), and had moderate airflow limitation (54.4%). The mean body mass index (BMI) of the study population was 23.1 kg/m², and 27.6% were obese or overweight. Hypertension was the most common comorbidity (37.6%). The mean blood eosinophil count was 226.8 cells/μL, with 21.9% of patients having ≥ 300 cells/μL. A clinically insignificant change in FEV1 (+1.4%) was observed a year after enrollment. Overall, patients experienced a mean of 0.2 severe annual AECOPD and approximately 1.1 mean moderate or severe AECOPD. Notably, the rates of severe AECOPD remained generally consistent over time. Compared with patients with no exacerbations, patients who experienced severe exacerbations had a lower mean BMI (21.7 vs. 23.1 kg/m²; P < 0.001) and lower lung function parameters (all P values < 0.001), but reported high rates of depression (25.5% vs. 15.1%; P = 0.044) and anxiety (37.3% vs. 16.7%; P < 0.001) as a comorbidity.

CONCLUSION

Findings from this Korean cohort of patients with COPD indicated a high exacerbation burden, which may be attributable to the unique characteristics of the study population and suboptimal disease management. This highlights the need to align clinical practices with the latest treatment recommendations to alleviate AECOPD burden in Korea.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT05750810.

Rate of severe exacerbations, healthcare resource utilisation and clinical outcomes in patients with COPD in low-income and middle-income countries: results from the EXACOS International Study

INTRODUCTION

The EXAcerbations of Chronic obstructive lung disease (COPD) and their OutcomeS (EXACOS) International Study aimed to quantify the rate of severe exacerbations and examine healthcare resource utilisation (HCRU) and clinical outcomes in patients with COPD from low-income and middle-income countries.

METHODS

EXACOS International was an observational, cross-sectional study with retrospective data collection from medical records for a period of up to 5 years. Data were collected from 12 countries: Argentina, Brazil, Chile, Colombia, Costa Rica, Dominican Republic, Guatemala, Hong Kong, Mexico, Panama, Russia and Taiwan. The study population comprised patients ≥40 years of age with COPD. Outcomes/variables included the prevalence of severe exacerbations, the annual rate of severe exacerbations and time between severe exacerbations; change in lung function over time (measured by the forced expiratory volume in 1 s (FEV1)); peripheral blood eosinophil counts (BECs) and the prevalence of comorbidities; treatment patterns; and HCRU.

RESULTS

In total, 1702 patients were included in the study. The study population had a mean age of 69.7 years, with 69.4% males, and a mean body mass index of 26.4 kg/m2. The mean annual prevalence of severe exacerbations was 20.1%, and 48.4% of patients experienced ≥1 severe exacerbation during the 5-year study period. As the number of severe exacerbations increased, the interval between successive exacerbations decreased. A statistically significant decrease in mean (SD) FEV1 from baseline to post-baseline was observed in patients with ≥1 severe exacerbation (1.23 (0.51) to 1.13 (0.52) L; p=0.0000). Mean BEC was 0.198 x109 cells/L, with 64.7% of patients having a BEC ≥0.1 x109 cells/L and 21.3% having a BEC ≥0.3 x109 cells/L. The most common comorbidity was hypertension (58.3%). An increasing number of severe exacerbations per year was associated with greater HCRU.

DISCUSSION

The findings presented here indicate that effective treatment strategies to prevent severe exacerbations in patients with COPD remain a significant unmet need in low-income and middle-income countries.

Efficacy of Nemiralisib in Chronic Obstructive Pulmonary Disease: A Systematic Review

PURPOSE

Chronic obstructive pulmonary disease (COPD) is a major public health concern. Exacerbation of COPD leads to poor health and frequent episodes of increased systemic and airway inflammation. Immunomodulatory drugs have garnered extensive attention because they may reduce the rate of COPD exacerbation. This review aimed to evaluate the efficacy and safety of nemiralisib in COPD patients.

METHODS

Medical databases, including the Cochrane Library, EMBASE, and PubMed, were queried from inception to June 2023 to identify randomized controlled trials (RCTs) on the efficacy of nemiralisib in COPD patients. This systematic review was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. The Cochrane Collaboration tool was used to assess the risk of bias of the included RCTs. Two authors independently conducted literature screening and data extraction. Key information from the included studies was extracted, tabulated, and compared using a data extraction table. Moreover, the key characteristics, quality, potential bias, and endpoint outcomes of the included studies were summarized. A meta-analysis was conducted when the study outcomes were sufficiently comparable, and the required data were available for extraction.

FINDINGS

Initially, 48 references were identified, leading to the inclusion of four trials. No significant difference was found between the nemiralisib and placebo groups in St George's Respiratory Questionnaire score, modified Medical Research Council Dyspnea Scale score, COPD Assessment Test score, time to next on-treatment exacerbation, proportion of patients achieving exacerbation recovery, time to exacerbation recovery, and rescue medication use. Contrastingly, the results demonstrated that nemiralisib may lower oral corticosteroid use during acute exacerbation of COPD. Meanwhile, the efficacy of nemiralisib on the exacerbation rate, as well as several parameters associated with lung function, including forced expiratory volume in 1 second, specific airway conductance, specific imaging airway wall thickness, distal specific imaging airway volume measured at functional residual capacity, specific imaging airway resistance, low attenuation score, and internal airflow lobar distribution in the lower pulmonary region, were conflicting. Attributed to the limited number of included RCTs and insufficient extracted data, it was not feasible to conduct a comprehensive meta-analysis.

IMPLICATIONS

Because of insufficient data, this systematic review could not make any definitive statement regarding the efficacy of nemiralisib in COPD patients. In terms of safety, nemiralisib was generally well tolerated. Further trials are required to explore the efficacy of this drug.

How to Enhance the Diagnosis of Early Stages of Chronic Obstructive Pulmonary Disease (COPD)? The Role of Mobile Spirometry in COPD Screening and Diagnosis-A Systematic Review

COPD is the third leading cause of death worldwide. Its diagnosis can be made with spirometry, which is underused due to its limited accessibility. Portable spirometry holds promise for enhancing the efficacy of COPD diagnoses. The study aimed to estimate COPD prevalence diagnosed with a portable spirometer in high-risk patients and compare it with COPD prevalence based on data from conventional, on-site spirometry. We also evaluated the strategy of a proactive approach to identify COPD in high-risk individuals. We conducted a systematic review of original studies on COPD targeted screening and diagnosis with portable and conventional spirometers selected from 8496 publications initially found in three databases: Cochrane, PubMed, and Embase. The inclusion criteria were met by 28 studies. COPD prevalence evaluated with the use of portable spirometers reached 20.27% and was lower compared to that estimated with the use of conventional spirometers (24.67%). In 11 included studies, postbronchodilator tests were performed with portable spirometers, which enabled a bedside COPD diagnosis. Portable spirometers can be successfully used in COPD targeted screening and diagnosis and thus enhance the detection of COPD at early stages.

A mRNA panel for differentiation between acute exacerbation or pneumonia in COPD patients

Introduction

Patients suffering from chronic obstructive pulmonary disease (COPD) are prone to acute exacerbations (AECOPD) or community acquired pneumonia (CAP), both posing severe risk of morbidity and mortality. There is no available biomarker that correctly separates AECOPD from COPD. However, because CAP and AECOPD differ in aetiology, treatment and prognosis, their discrimination would be important.

Methods

This study analysed the ability of selected candidate transcripts from peripheral blood mononuclear cells (PBMCs) to differentiate between patients with AECOPD, COPD & CAP, and CAP without pre-existing COPD.

Results

In a previous study, we identified differentially regulated genes between CAP and AECOPD in PBMCs. In the present new cohort, we tested the potential of selected candidate PBMC transcripts to differentiate at early time points AECOPD, CAP+COPD, and CAP without pre-existing COPD. Expression of YWHAG, E2F1 and TDRD9 held predictive power: This gene set predicted diseases markedly better (model accuracy up to 100%) than classical clinical markers like CRP, lymphocyte count and neutrophil count (model accuracy up to 82%).

Discussion

In summary, in our cohort expression levels of YWHAG, E2F1 and TDRD9 differentiated with high accuracy between COPD patients suffering from acute exacerbation or CAP.

Severe Acute Exacerbations of Chronic Obstructive Pulmonary Disease: Are There Significant Differences Between Hospitalized and Emergency Department Patients?

Rationale

Current guidelines define a severe acute exacerbation of chronic obstructive pulmonary disease (AECOPD) as an increase in symptoms requiring hospital admission or emergency department (ED) visit. Little is known about whether or not subjects requiring hospitalization and those needing only ED care have similar patient profiles and if their clinical outcomes appear comparable.

Objective

The main goals of this study were to compare the demographic and clinical characteristics of patients treated for an AECOPD with an inpatient admission versus an ED visit and to review if hospital resource utilization was different between the 2 groups after discharge.

Methods

Subjects treated in 2022 at Montfort Hospital for an AECOPD were reviewed. Patient demographic information was collected in addition to spirometry results and blood eosinophil counts on file. Supplemental oxygen use and medication lists were also recorded. Patients with an initial hospital admission were compared to those requiring only ED care with univariate and multivariate analyses. We also assessed if subjects were again treated for an AECOPD up to 6 months post initial discharge, and if so, the type of hospital visits (hospitalization or ED).

Measurements and Main Results

A total of 135 individuals necessitated hospitalization and 79 received ED care for the treatment of an AECOPD. On univariate analysis, patients requiring an inpatient stay appeared older and were more likely to have spirometry results on file. A greater proportion of hospitalized individuals were on supplemental oxygen and prescribed at least one long-acting inhaled medication. These studied variables remained significant after multivariate logistic regression analysis. Subjects with an initial inpatient admission were also more likely to require hospitalization upon repeat presentation for a severe AECOPD.

Conclusion

Given the important differences observed in both patient characteristics and hospital resource utilization, this study supports considering an AECOPD requiring inpatient admission versus an ED visit as distinct categories of events.

The Causal Relationship Between Gastroesophageal Reflux Disease and Chronic Obstructive Pulmonary Disease: A Bidirectional Two-Sample Mendelian Randomization Study

Background

Gastroesophageal reflux disease (GERD) and Chronic Obstructive Pulmonary Disease (COPD) often coexist and have been associated in observational studies. However, the real potential causal relationship between GERD and COPD is unknown and not well established.

Methods

In this study, we conducted a bidirectional two-sample Mendelian randomization(MR) to estimate whether GERD and COPD are causal. The GERD genetic data is from summary level data of a genome-wide association (GWAS) meta-analysis (Ncases = 71,522, Ncontrol=26,079). The COPD GWAS are available from the FinnGen (Ncases=16,410, Ncontrol=283,589). MR-Egger regression, Weighted Median, and Inverse-variance weighted (IVW) were used for MR analysis from the R package "TwoSampleMR", and IVW was the dominant estimation method. Additionally, the MR pleiotropy residual sum and outlier (MR-PRESSO), Cochran Q statistic, and leave-one-out analysis were used to detect and correct for the effect of heterogeneity and horizontal pleiotropy.

Results

MR analysis indicated that GERD was causally associated with an increased risk of COPD (IVW odds ratio (OR): 1.3760, 95% confidence interval (CI): 1.1565-1.6371, P=0.0003), and vice versa (IVW OR: 1.1728, 95% CI:1.0613-1.2961, P=0.0018). The analyses did not reveal any pleiotropy or heterogeneity.

Conclusion

Our study revealed possible evidence for a bidirectional causal relationship between GERD and COPD. Implementing screening and preventive strategies for GERD in individuals with COPD, and vice versa, will be crucial in future healthcare management. Further studies are needed to elucidate the mechanisms underlying the causal relationship between GERD and COPD.

Inhaled corticosteroids with combination inhaled long-acting beta2-agonists and long-acting muscarinic antagonists for chronic obstructive pulmonary disease

BACKGROUND

Management of chronic obstructive pulmonary disease (COPD) commonly involves a combination of long-acting bronchodilators including beta2-agonists (LABA) and muscarinic antagonists (LAMA). LABA and LAMA bronchodilators are now available in single-combination inhalers. In individuals with persistent symptoms or frequent exacerbations, inhaled corticosteroids (ICS) are also used with combination LABA and LAMA inhalers. However, the benefits and risks of adding ICS to combination LABA/LAMA inhalers as a triple therapy remain unclear.

OBJECTIVES

To assess the effects of adding an ICS to combination LABA/LAMA inhalers for the treatment of stable COPD.

SEARCH METHODS

We searched the Cochrane Airways Group Register of Trials, Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, and Embase up to 30 November 2022. We also searched ClinicalTrials.gov and the WHO ICTRP up to 30 November 2022.

SELECTION CRITERIA

We included parallel-group randomised controlled trials of three weeks' duration or longer that compared the treatment of stable COPD with ICS in addition to combination LABA/LAMA inhalers against combination LABA/LAMA inhalers alone.

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methodological procedures. The primary outcomes were acute exacerbations of COPD, respiratory health-related quality of life, pneumonia and other serious adverse events. The secondary outcomes were symptom scores, lung function, physical capacity, and mortality. We used GRADE to assess certainty of evidence for studies that contributed data to our prespecified outcomes.

MAIN RESULTS

Four studies with a total of 15,412 participants met the inclusion criteria. The mean age of study participants ranged from 64.4 to 65.3 years; the proportion of female participants ranged from 28% to 40%. Most participants had symptomatic COPD (COPD Assessment Test Score ≥ 10) with severe to very severe airflow limitation (forced expiratory volume in one second (FEV1) < 50% predicted) and one or more moderate-to-severe COPD exacerbations in the last 12 months. Trial medications differed amongst studies. The duration of follow-up was 52 weeks in three studies and 24 weeks in one study. We assessed the risk of selection, performance, and detection bias to be low in the included studies; one study was at high risk of attrition bias, and one study was at high risk of reporting bias. Triple therapy may reduce rates of moderate-to-severe COPD exacerbations compared to combination LABA/LAMA inhalers (rate ratio (RR) 0.74, 95% confidence interval (CI) 0.67 to 0.81; n = 15,397; low-certainty evidence). Subgroup analysis stratifying by blood eosinophil counts showed there may be a greater reduction in rate of moderate-to-severe COPD exacerbations with triple therapy in participants with high-eosinophils (RR 0.67, 95% CI 0.60 to 0.75) compared to low-eosinophils (RR 0.87, 95% CI 0.81 to 0.93) (test for subgroup differences: P < 0.01) (high/low cut-offs: 150 eosinophils/µL in three studies; 200 eosinophils/µL in one study). However, moderate-to-substantial heterogeneity was observed in both high- and low-eosinophil subgroups. These subgroup analyses are observational by nature and thus results should be interpreted with caution. Triple therapy may be associated with reduced rates of severe COPD exacerbations (RR 0.75, 95% CI 0.67 to 0.84; n = 14,131; low-certainty evidence). Triple therapy improved health-related quality of life assessed using the St George's Respiratory Questionnaire (SGRQ) by the minimal clinically important difference (MCID) threshold (4-point decrease) (35.3% versus 42.4%, odds ratio (OR) 1.35, 95% CI 1.26 to 1.45; n = 14,070; high-certainty evidence). Triple therapy may result in fewer symptoms measured using the Transition Dyspnoea Index (TDI) (OR 1.33, 95% CI 1.13 to 1.57; n = 3044; moderate-certainty evidence) and improved lung function as measured by change in trough FEV1 (mean difference 38.68 mL, 95% CI 22.58 to 54.77; n = 11,352; low-certainty evidence). However, these benefits fell below MCID thresholds for TDI (1-unit decrease) and trough FEV1 (100 mL), respectively. Triple therapy is probably associated with a higher risk of pneumonia as a serious adverse event compared to combination LABA/LAMA inhalers (3.3% versus 1.9%, OR 1.74, 95% CI 1.39 to 2.18; n = 15,412; moderate-certainty evidence). In contrast, all-cause serious adverse events may be similar between groups (19.7% versus 19.7%, OR 0.95, 95% CI 0.87 to 1.03; n = 15,412; low-certainty evidence). All-cause mortality may be lower with triple therapy (1.4% versus 2.0%, OR 0.70, 95% CI 0.54 to 0.90; n = 15,397; low-certainty evidence).

AUTHORS' CONCLUSIONS

The available evidence suggests that triple therapy may reduce rates of COPD exacerbations (low-certainty evidence) and results in an improvement in health-related quality of life (high-certainty evidence) compared to combination LABA/LAMA inhalers, but probably confers an increased pneumonia risk as a serious adverse event (moderate-certainty evidence). Triple therapy probably improves respiratory symptoms and may improve lung function (moderate- and low-certainty evidence, respectively); however, these benefits do not appear to be clinically significant. Triple therapy may reduce the risk of all-cause mortality compared to combination LABA/LAMA inhalers (low-certainty evidence). The certainty of the evidence was downgraded most frequently for inconsistency or indirectness. Across the four included studies, there were important differences in inclusion criteria, trial medications, and duration of follow-up. Investigation of heterogeneity was limited due to the small number of included studies. We found limited data on the effects of triple therapy compared to combination LABA/LAMA inhalers in patients with mild-moderate COPD and those without a recent exacerbation history.

Analyses of Factors Associated with Acute Exacerbations of Chronic Obstructive Pulmonary Disease: A Review

Acute exacerbations of chronic obstructive pulmonary disease (AECOPD) is the exacerbation of a range of respiratory symptoms during the stable phase of chronic obstructive pulmonary disease (COPD). AECOPD is thus a dangerous stage and key event in the course of COPD, as its deterioration and frequency seriously affects the quality of life of patients and shortens their survival. Acute exacerbations occur and develop due to many factors such as infection, tobacco smoke inhalation, air pollution, comorbidities, airflow limitation, various biomarkers, history of previous deterioration, natural killer cell abnormalities, immunoglobulin G deficiency, genetics, abnormal muscle and nutritional status, negative psychology, and seasonal temperature changes. There is relatively limited research on the impact of the role of standardized management on the alleviation of AECOPD. However, with the establishment of relevant prevention and management systems and the promotion of artificial intelligence technology and Internet medical approaches, long-term effective and standardized management of COPD patients may help to achieve the quality of life and disease prognosis in COPD patients and reduce the risk of AE.

Using an electronic diary and wristband accelerometer to detect exacerbations and activity levels in COPD: a feasibility study

Background

Early and accurate identification of acute exacerbations of COPD may lead to earlier treatment and prevent hospital admission. Electronic diaries have been developed for symptom monitoring and accelerometers to monitor activity. However, it is unclear whether this technology is usable in the COPD population. This study aimed to assess the feasibility of an electronic diary (eDiary) for symptom reporting using the MoreCare app and activity monitoring with the Garmin Vivofit 2 in COPD.

Methods

Participants were recruited from the London COPD Cohort. Participants were provided a Garmin Vivofit 2 activity monitor and an android tablet with the MoreCare app for a period of 3 months.

Results

25 COPD patients were recruited (mean±sd age 70.8±7.1 years, forced expiratory volume in 1 s (FEV1) 49.8±14.8% predicted). Age, gender, disease severity and exacerbation frequency had no impact on eDiary compliance. There was a moderate positive correlation between median daily very active minutes and FEV1 % pred (ρ=0.62, p=0.005). Daily step counts decreased during the initial 7 days of exacerbation and recovery compared to a pre-exacerbation baseline. A decision-tree model identified change in sputum colour, change in step count, severity of cold, exacerbation history and use of rescue medication as the most important predictors of acute exacerbations of COPD in this cohort.

Conclusions

Symptom and activity monitoring using digital technology is feasible in COPD. Further large-scale digital health studies are needed to assess whether eDiaries can be used to identify patients at risk of exacerbation and guide early intervention.

A Double-Blind, Randomized, Placebo-controlled Trial of Long-Term Doxycycline Therapy on Exacerbation Rate in Patients with Stable Chronic Obstructive Pulmonary Disease

Rationale: Chronic obstructive pulmonary disease (COPD) exacerbations are a major cause of morbidity and mortality, and preventing them is a key treatment target. Long-term macrolide treatment is effective at reducing exacerbations, but there is a paucity of evidence for other antibiotic classes. Objectives: To assess whether 12-month use of doxycycline reduces the exacerbation rate in people with COPD. Methods: People with moderate to very severe COPD and an exacerbation history were recruited from three UK centers and randomized to 12 months of doxycycline 100 mg once daily or placebo. The primary study outcome was the exacerbation rate per person-year. Results: A total of 222 people were randomized. Baseline mean FEV1 was 1.35 L (SD, 0.35 L), 52.5% predicted (SD, 15.9% predicted). The median number of treated exacerbations in the year before the study was 2 (SD, 1-4). A total of 71% of patients reported two or more exacerbations, and 81% were already prescribed inhaled corticosteroids at baseline. The COPD exacerbation rate did not differ between the groups (doxycycline/placebo rate ratio [RR], 0.86; 95% confidence interval [CI], 0.67-1.10; P = 0.23). No difference was seen if only treated exacerbations or hospitalizations were considered. In preplanned subgroup analysis, doxycycline appeared to better reduce the exacerbation rate among people with severe COPD (RR, 0.36; 95% CI, 0.15-0.85; P = 0.019) and in those with an eosinophil count <300 cells/μl (RR, 0.50; 95% CI, 0.29-0.84; P = 0.01). Health status measured by St. George's Respiratory Questionnaire was 5.2 points worse in the doxycycline group at 12 months (P < 0.007). Conclusions: Doxycycline did not significantly reduce the exacerbation rate, over 12 months, in participants with COPD who exacerbated regularly, but it may have benefitted those with more severe COPD or blood eosinophil counts <300 cells/μl. Clinical trial registered with www.clinicaltrials.gov (NCT02305940).

[COPD - what has changed in GOLD 2023 and is relevant for clinical practice?]

The annual report of the Global Initiative for Chronic Obstructive Lung Disease (GOLD) is one of the most relevant documents covering prevention, diagnosis and treatment of chronic obstructive pulmonary disease (COPD). The 2023 edition contains a number of changes with impact on clinical practice. For assessment and categorization, a new patient group termed E based on individual exacerbation history has been introduced. The basis of pharmacological management for most patients is the use of combinations containing a long acting β2-agonist (LABA) and a long-acting anticholinergic (LAMA). Combinations of LABA and inhaled corticosteroids (ICS) are no longer recommended. When there is an indication for ICS therapy, a combination of LABA, LAMA and ICS should be used. For these triple combinations, a significant reduction of mortality could be demonstrated in selected patient populations. GOLD proposes a new definition and assessment of COPD exacerbations focussing on objectively assessible parameters and relevant differential diagnoses.

Reduced quantity and function of pneumococcal antibodies are associated with exacerbations of COPD in SPIROMICS

While hypogammaglobulinemia is associated with COPD exacerbations, it is unknown whether frequent exacerbators have specific defects in antibody production/function. We hypothesized that reduced quantity/function of serum pneumococcal antibodies correlate with exacerbation risk in the SPIROMICS cohort. We measured total pneumococcal IgG in n = 764 previously vaccinated participants with COPD. In a propensity-matched subset of n = 200 with vaccination within five years (n = 50 without exacerbations in the previous year; n = 75 with one, n = 75 with ≥2), we measured pneumococcal IgG for 23 individual serotypes, and pneumococcal antibody function for 4 serotypes. Higher total pneumococcal IgG, serotype-specific IgG (17/23 serotypes), and antibody function (3/4 serotypes) were independently associated with fewer prior exacerbations. Higher pneumococcal IgG (5/23 serotypes) predicted lower exacerbation risk in the following year. Pneumococcal antibodies are inversely associated with exacerbations, supporting the presence of immune defects in frequent exacerbators. With further study, pneumococcal antibodies may be useful biomarkers for immune dysfunction in COPD.

Analysis of the correlation between BMI and respiratory tract microbiota in acute exacerbation of COPD

Objective

To investigate the distribution differences in the respiratory tract microbiota of AECOPD patients in different BMI groups and explore its guiding value for treatment.

Methods

Sputum samples of thirty-eight AECOPD patients were collected. The patients were divided into low, normal and high BMI group. The sputum microbiota was sequenced by 16S rRNA detection technology, and the distribution of sputum microbiota was compared. Rarefaction curve, α-diversity, principal coordinate analysis (PCoA) and measurement of sputum microbiota abundance in each group were performed and analyzed by bioinformatics methods.

Results

1. The rarefaction curve in each BMI group reached a plateau. No significant differences were observed in the OTU total number or α-diversity index of microbiota in each group. PCoA showed significant differences in the distance matrix of sputum microbiota between the three groups, which was calculated by the Binary Jaccard and the Bray Curtis algorithm. 2. At the phylum level, most of the microbiota were Proteobacteria, Bacteroidetes Firmicutes, Actinobacteria, and Fusobacteria. At the genus level, most were Streptococcus, Prevotella, Haemophilus, Neisseria and Bacteroides. 3. At the phylum level, the abundance of Proteobacteria in the low group was significantly higher than that in normal and high BMI groups, the abundances of Firmicutes in the low and normal groups were significantly lower than that in high BMI groups. At the genus level, the abundance of Haemophilus in the low group was significantly higher than that in high BMI group, and the abundances of Streptococcus in the low and normal BMI groups were significantly lower than that in the high BMI group.

Conclusions

1. The sputum microbiota of AECOPD patients in different BMI groups covered almost all microbiota, and BMI had no significant association with total number of respiratory tract microbiota or α-diversity in AECOPD patients. However, there was a significant difference in the PCoA between different BMI groups. 2. The microbiota structure of AECOPD patients differed in different BMI groups. Gram-negative bacteria (G-) in the respiratory tract of patients predominated in the low BMI group, while gram-positive bacteria (G+) predominated in the high BMI group.

Inter-relationships among neutrophilic inflammation, air trapping and future exacerbation in COPD: an analysis of ECOPD study

BACKGROUND

The inter-relationships among neutrophilic airway inflammation, air trapping and future exacerbation in chronic obstructive pulmonary disease (COPD) remain unclear.

OBJECTIVE

To evaluate the associations between sputum neutrophil proportions and future exacerbation in COPD and to determine whether these associations are modified by significant air trapping.

METHODS

Participants with completed data were included and followed up to the first year in the Early Chronic Obstructive Pulmonary Disease study (n=582). Sputum neutrophil proportions and high-resolution CT-related markers were measured at baseline. Sputum neutrophil proportions were dichotomised based on their median (86.2%) to low and high levels. In addition, subjects were divided into the air trapping or non-air trapping group. Outcomes of interest included COPD exacerbation (separately any, severe and frequent exacerbation, occurring in the first year of follow-up). Multivariable logistic regressions were performed to examine the risk of severe exacerbation and frequent exacerbation with either neutrophilic airway inflammation groups or air trapping groups.

RESULTS

There was no significant difference between high and low levels of sputum neutrophil proportions in the exacerbation in the preceding year. After the first year of follow-up, subjects with high sputum neutrophil proportions had increased risks of severe exacerbation (OR=1.68, 95% CI: 1.09 to 2.62, p=0.020). Subjects with high sputum neutrophil proportions and significant air trapping had increased odds of having frequent exacerbation (OR=3.29, 95% CI: 1.30 to 9.37, p=0.017) and having severe exacerbation (OR=2.72, 95% CI: 1.42 to 5.43, p=0.003) when compared with those who had low sputum neutrophil proportions and non-air trapping.

CONCLUSIONS

We found that subjects with high sputum neutrophil proportions and significant air trapping are prone to future exacerbation of COPD. It may be a helpful predictor of future exacerbation.

Better response to Tanreqing injection in frequent acute exacerbation of chronic obstructive pulmonary disease (AECOPD) patients—Real-world evidence from a nationwide registry (ACURE) study

Objective: Our aim was to systematically investigate the efficacy of Tanreqing (TRQ) injection on in-hospital outcomes among inpatients with frequent or infrequent AECOPD.

Methods: In this ongoing, nationwide multicenter registry designed to investigate clinical characteristics, management, and prognoses of Chinese patients admitted for AECOPD in real-world settings, we collected characteristics, comorbidities, in-hospital prognoses, and information on the COPD assessment test (CAT) questionnaire, PEACE questionnaire, and modified British Medical Research Council (mMRC) questionnaire from each enrolled patient. Frequent AECOPD was determined as being admitted to the hospital ≥1 time or visiting the emergency room (ER) ≥ 2 times due to AECOPD within a year. A propensity match method and univariable and multivariable regression models were performed to analyze the efficacy of TRQ on clinical outcomes for inpatients with frequent AECOPD.

Results: A total of 4135 inpatients were involved in the analysis, including 2179 administered with TRQ and 1956 not administered with TRQ. Among those administered with TRQ, 493 had frequent AECOPD and 358 had infrequent AECOPD. After a propensity score match, a significant reduction of CAT score at discharge (TRQ median 12, IQR 8.0–16.0; non-TRQ median 13, IQR 9.0–18.0, p = 0.0297), a lower rate of ICU admission (TRQ 0.8% vs. non-TRQ 2.6%, p = 0.0191), and a shorter length of stay (LOS) (TRQ median 11, IQR 9.0–14.0; non-TRQ median 11, IQR 8.0–14.0, p = 0.004) were observed in the TRQ group, compared with the non-TRQ group among frequent AECOPD patients. In the subgroup analysis, for those with a PEACE score &gt;7 on admission, TRQ contributed to a significantly lower CAT score at discharge (p = 0.0084) and a numerically lower ICU admission rate with a marginal statistical significance. Among those with phlegm-heat symptom complex on admission ≥2, a lower CAT score at discharge and a lower ICU admission were also observed in the TRQ group.

Conclusion: TRQ injection had better efficacy in patients with frequent AECOPD in reducing ICU admission and alleviating respiratory symptoms, especially for those with higher severity on admission or more phlegm-heat symptoms.

Impact of Previous Pulmonary Tuberculosis on Chronic Obstructive Pulmonary Disease: Baseline Results from a Prospective Cohort Study

OBJECTIVE

Pulmonary tuberculosis (PTB) is a significant risk factor for COPD, and Xinjiang, China, has a high incidence of pulmonary tuberculosis. The effects of tuberculosis history on airflow restriction, clinical symptoms, and acute episodes in COPD patients have not been reported in the local population. Besides, the exact relationship between lung function changes in people with a history of tuberculosis and COPD risk is not clear.

METHODS

This study is based on the Xinjiang baseline survey data included in the Natural Population Cohort Study in Northwest China from June to December, 2018. Subjects' questionnaires, physical examination, and lung function tests were performed through a face-to-face field survey to analyze the impact of previous pulmonary tuberculosis on local COPD. Furthermore, we clarified the specific relationship between pulmonary function decline and the probability of developing COPD in people with a history of tuberculosis.

RESULTS

A total of 3249 subjects were eventually enrolled in this study, including 87 with a history of tuberculosis and 3162 non-TB. The prevalence of COPD in the prior TB group was significantly higher than that in the control group (p-value = 0.005). First, previous pulmonary tuberculosis is an essential contributor to airflow limitation in the general population and patients with COPD. In all subjects included, pulmonary function, FEV1% predicted (p-value < 0.001), and FEV1/FVC (%) (p-value < 0.001) were significantly lower in the prior TB group than in the control group. Compared to non-TB group, FEV1% prediction (p-value = 0.019) and FEV1/FVC (%) (p-value = 0.016) were found to be significantly reduced, and airflow restriction (p-value = 0.004) was more severe in prior TB group among COPD patients. Second, COPD patients in the prior TB group had more severe clinical symptoms. Compared with no history of tuberculosis, mMRC (p-value = 0.001) and CAT (p-value = 0.002) scores were higher in the group with a history of tuberculosis among COPD patients. Third, compared with the non-TB group, the number of acute exacerbations per year (p-values=0.008), the duration of each acute exacerbation (p-values=0.004), and hospitalization/ patient/year (p-values<0.001) were higher in the group with a history of tuberculosis among COPD patients. Finally, a dose-response relationship between FEV1/FVC (%) and the probability of developing COPD in people with previous pulmonary TB was observed; when FEV1/FVC (%) was < 80.8, the risk of COPD increased by 13.5% per unit decrease in lung function [0.865(0.805, 0.930)].

CONCLUSION

COPD patients with previous pulmonary tuberculosis have more severe airflow limitations and clinical symptoms and are at higher risk for acute exacerbations. Furthermore, lung function changes in people with a history of tuberculosis were associated with a dose-response relationship with the probability of developing COPD.

Relationship of COPD Exacerbation Severity and Frequency on Risks for Future Events and Economic Burden in the Medicare Fee-For-Service Population

Purpose

To quantify the effects of moderate and/or severe chronic obstructive pulmonary disease (COPD) exacerbations on future exacerbations and healthcare costs in Medicare Fee-For-Service beneficiaries.

Patients and Methods

A retrospective cohort study of patients ≥40 years of age, with continuous enrollment from 2015 to 2018, with an index COPD diagnosis defined as first hospitalization, emergency department visit, or first of two outpatient visits (≥30 days apart) in 2015 with a claim for chronic bronchitis, emphysema, or chronic airway obstruction. Patients were stratified by baseline exacerbation categories in year one (YR1) and subsequently evaluated in YR2 and YR3: (A) none; (B) 1 moderate; (C) ≥2 moderate; (D) 1 severe; and (E) ≥2, one being severe. Moderate exacerbations were defined as COPD-related outpatient/ED visits with a corticosteroid/antibiotic claim within ±7 days of the visit and severe exacerbations as hospitalizations with a primary COPD diagnosis. Total all-cause costs for Categories B-E were compared to reference Category A using generalized linear models and inflation adjusted to 2019 dollars.

Results

A total of 1,492,108 patients met study criteria with a mean (±SD) age of 70.9±10.9. In YR1, nearly 40% of patients experienced ≥1 moderate and/or severe exacerbations. Patients having multiple exacerbations, regardless of severity were 2–4 times more likely to experience an exacerbation during YR2 and YR3. Adjusted costs ranged between $24,000 and $26,600 for all categories for YR2 and YR3. Adjusted YR2 costs for Category D and E were $1421 and $1548 higher than those without an exacerbation (Category A YR2 $25,084, YR3 $24,282; p<0.0001). The respective YR3 adjusted costs were $2062 and $2117 higher than those without an exacerbation (Category A; p<0.0001), representing an increase of 6–8% and 8–9% for YR2 and YR3.

Conclusion

Medicare patients with recent moderate or severe exacerbations, or at least two exacerbations per year are at significant risk for future exacerbations and incur higher all-cause costs.

Terms and Definitions Used to Describe Recurrence, Treatment Failure and Recovery of Acute Exacerbations of COPD: A Systematic Review of Observational Studies

Introduction

Acute exacerbations of chronic obstructive pulmonary disease (AECOPDs) are important clinical events, with many patients experiencing multiple AECOPDs annually. The terms used in the literature to define recurring AECOPD events are inconsistent and may impact the ability to describe the true burden of these events. We undertook a systematic review to identify and summarize terms and definitions used in observational studies to describe AECOPD-related events occurring after an initial AECOPD (hereafter “subsequent AECOPD”).

Methods

PubMed was searched (2000–2019) for observational studies on subsequent AECOPD events using broad search strings for “COPD”, “exacerbation”, and “subsequent exacerbation events”. Only English-language studies were included. Small studies (n<50) and studies focusing on hospital re-admission only were excluded. Extracted data were analyzed descriptively to generate a narrative summary, using a thematic approach to group studies utilizing similar terms for subsequent AECOPD.

Results

Forty-seven studies were included. No single, distinct terms or definitions were used to define and identify multiple occurrences of AECOPDs, though most (46) studies used one or more of four clustered terms and definitions: reapse (n = 13), recurrence/re-exacerbation (n = 11), treatment failure (n = 12) and non-recovery/time to recovery (n = 16). Heterogeneity was observed within and between the four clusters with respect to study setting, starting point for observing subsequent AECOPDs, time frame to identify a subsequent AECOPD (except for studies using “time to recovery”), and basis for identifying a subsequent exacerbation.

Conclusion

Our review demonstrates that subsequent AECOPDs (including events such as relapse, recurrence/re-exacerbation, treatment failure, non-recovery/time to recovery) are ill-defined in the observational study literature, emphasizing the need to reach consensus on precise and objective definitions (for example, when one AECOPD ends and another begins). Use of standardized terminology and definitions may aid comparability between, and synthesis of, studies, thus improving the understanding of the natural history and burden of exacerbations in COPD patients.

Association of baseline parameters with year 0 and year 1 acute exacerbations in male patients with chronic obstructive pulmonary disease

Objectives

Acute exacerbations (AEs) of chronic obstructive pulmonary disease (COPD) can affect health status, hospitalization and readmission rates, and disease progression. This study aimed to identify independent markers associated with COPD AEs.

Methods

This study included male patients with COPD and collected data regarding their AEs and baseline clinical parameters.

Results

We included 149 male patients. Among them, 58 were included in the year 0 high-AE group and 91 in the low-AE group. Multivariate analysis revealed that the high-AE group had higher white blood cell count, lower serum albumin level, and post-bronchodilator (BD) forced expiratory volume in one second (FEV₁) (%) with a combined receiver operating characteristic curve (ROC) of 0.721 (p < 0.001). Additionally, 34 patients were included in the year 1 high-AE group and 70 in the low-AE group (p < 0.001). Multivariate analysis revealed that the high-AE group had higher platelet count, positive asthma history, and lower pre-BD FEV₁ (%) with a combined ROC of 0.782 (p < 0.001).

Conclusion

In male patients with COPD, baseline white blood cell count, albumin level, and post-BD FEV₁ (%) were correlated with year 0 AE; on the other hand, baseline platelet count, positive asthma history, and pre-BD FEV₁ (%) were associated with year 1 AE.

Prediction of Acute COPD Exacerbation in the Swiss Multicenter COPD Cohort Study (TOPDOCS) by Clinical Parameters, Medication Use, and Immunological Biomarkers

BACKGROUND AND OBJECTIVE

Whether immunological biomarkers combined with clinical characteristics measured during an exacerbation-free period are predictive of acute exacerbation of chronic obstructive pulmonary disease (AECOPD) frequency and severity is unknown.

METHOD

We measured immunological biomarkers and clinical characteristics in 271 stable chronic obstructive pulmonary disease (COPD) patients (67% male, mean age 63 years) from "The Obstructive Pulmonary Disease Outcomes Cohort of Switzerland" cohort on a single occasion. One-year follow-up data were available for 178 patients. Variables independently associated with AECOPD frequency and severity were identified by multivariable regression analyses. Receiver operating characteristic analysis was used to obtain optimal cutoff levels and measure the area under the curve (AUC) in order to assess if baseline data can be used to predict future AECOPD.

RESULTS

Higher number of COPD medications (adjusted incident rate ratio [aIRR] 1.17) and platelet count (aIRR 1.03), and lower FEV1% predicted (aIRR 0.84) and IgG2 (aIRR 0.84) were independently associated with AECOPD frequency in the year before baseline. Optimal cutoff levels for experiencing frequent (>1) AECOPD were ≥3 COPD medications (AUC = 0.72), FEV1 ≤40% predicted (AUC = 0.72), and IgG2 ≤2.6 g/L (AUC = 0.64). The performance of a model using clinical and biomarker parameters to predict future, frequent AECOPD events in the same patients was fair (AUC = 0.78) but not superior to a model using only clinical parameters (AUC = 0.79). The IFN-lambda rs8099917GG-genotype was more prevalent in patients who had severe AECOPD.

CONCLUSIONS

Clinical and biomarker parameters assessed at a single point in time correlated with the frequency of AECOPD events during the year before and the year after assessment. However, only clinical parameters had fair discriminatory power in identifying patients likely to experience frequent AECOPD.

The prognostic factors of in-hospital death among patients with pneumonic COPD acute exacerbation

BACKGROUND

Pneumonic acute exacerbation of chronic obstructive pulmonary disease (COPD-AE) is associated with worse outcomes compared with non-pneumonic COPD-AE. We aimed to explore prognostic factors among patients with pneumonic COPD-AE.

METHODS

This multicentered retrospective cohort study was conducted across five hospitals in Japan. Hospitalized patients ≥40 years of age with pneumonic COPD-AE who were administered systemic corticosteroids during hospitalization were included. Patients with other causes of respiratory failure, daily systemic steroid users, and patients who were not treated with systemic steroids were excluded. Based on existing clinical prediction models, the following potential prognostic factors were selected in advance: age, blood eosinophil count, blood urea nitrogen, respiratory rate, diastolic blood pressure, and altered mental status. Multivariate logistic regression was conducted to determine the association between potential prognostic factors and in-hospital death.

RESULTS

After excluding 897 patients based on the exclusion criteria, 669 patients with pneumonic COPD-AE who were administered systemic corticosteroids were included. The in-hospital mortality rate was 5.1%. Altered mental status was associated with mortality (odds ratio, 4.47; 95% confidence intervals, 2.00 to 10.00), and eosinophilia was associated with a lower risk of mortality (odds ratio, 0.19; 95% confidence intervals: 0.06 to 0.56).

CONCLUSIONS

Altered mental status may be a prognostic factor for in-hospital death among patients with pneumonic COPD-AE who were administered systemic corticosteroids. Moreover, eosinophilia may be a prognostic factor for lower in-hospital mortality rate among these patients.

Chinese Medical Injections for Acute Exacerbation of Chronic Obstructive Pulmonary Disease: A Network Meta-analysis

BACKGROUND

The World Health Organization has indicated that chronic obstructive pulmonary disease (COPD) may become the third leading cause of death by 2030. Acute exacerbation of COPD (AECOPD) is an important process in clinical treatment. Recent studies have shown that Chinese medical injections (CMI) are effective against AECOPD, but the effective difference among different CMIs remains unclear. The aim of this network meta-analysis (NMA) is to compare the therapeutic effect of various CMIs.

METHODS

We conducted an overall, systematic literature search in the China National Knowledge Infrastructure, Wanfang, VIP, SinoMed, PubMed, Embase, Cochrane Library, and Web of Science databases to retrieve randomized controlled trials (RCTs) of CMIs for AECOPD published up to January 2021. The Cochrane risk of bias tool was used to assess the risk of bias. Stata 13.1 and WinBUGS 14.3 were used for data analyses.

RESULTS

In total, 103 RCTs involving 8767 participants and 23 CMIs were included. The results indicated that among all treatments conventional Western medical therapy (WM) plus Dengzhanxixin injection (DZXX) led to the best improvement in the clinical efficacy and the ratio of forced expiratory volume in one second (FEV1) to forced vital capacity (FVC) (FEV1/FVC), with surface under the cumulative ranking curve (SUCRA)=80.47% and 98.55%, respectively. Moreover, Shenmai injection (SM) plus WM and Reduning injection (RDN) plus WM led to the best improvement in the FEV1 (SUCRA=80.18%) and the ratio of forced expiratory volume in one second to the predicted value (FEV1%, SUCRA=87.28%). Shengmai injection (SGM) plus WM led to the most considerable shortening in the length of hospital stay (SUCRA=94.70%). Cluster analysis revealed that WM+DZXX had the most favorable response for clinical efficacy and FEV1, as well as clinical efficacy and FEV1/FVC, WM+RDN had the most favorable response for clinical efficacy and FEV1%, WM+SGM had the most favorable response for clinical efficacy and length of hospital stay.

CONCLUSION

WM+DZXX, WM+RDN, and WM+SGM were noted to be the optimum treatment regimens for improving in clinical efficacy, FEV1, FEV1/FVC, FEV1% and reducing the hospital stay length of AECOPD patients. Considering the limitations this NMA may have, the current results warrant further verification via additional high-quality studies.

Prevalence and predictors of pulmonary embolism in patients with acute exacerbation of chronic obstructive pulmonary disease

Background:

The prevalence of pulmonary embolism (PE) in patients of acute exacerbation of chronic obstructive pulmonary disease (AECOPD) varies over a wide range. Early detection and treatment of PE in AECOPD is a key to improve patient outcome. The purpose of the study was to investigate the prevalence and predictors of PE in patients of AECOPD in a high burden region of North India.

Materials and Methods:

This prospective study included patients of AECOPD with no obvious cause of exacerbation on initial evaluation. Apart from routine workup, the participants underwent assessment of D-dimer, compression ultrasound and venous Doppler ultrasound of the lower limbs and pelvic veins, and a multidetector computed tomography pulmonary angiography.

Results:

A total of 100 patients of AECOPD with unknown etiology were included. PE as a possible cause of AE-COPD was observed in 14% of patients. Among the participants with PE, 63% (n = 9) had a concomitant presence of lower extremity deep venous thrombosis. Hemoptysis and chest pain were significantly higher in patients of AECOPD with PE ([35.7% vs. 7%, P = 0.002] and [92.9% vs. 38.4%, P = 0.001]). Likelihood of PE was significantly higher in patients who presented with tachycardia, tachypnea, respiratory alkalosis (PaCO2 <45 mmHg and pH >7.45), and hypotension. No difference was observed between the two groups in terms of in-hospital mortality, age, sex distribution, and risk factors for embolism except for the previous history of venous thromboembolism (35.7% vs. 12.8% P = 0.03).

Conclusion:

PE was probably responsible for AECOPD in 14% of patients with no obvious cause on initial assessment. Patients who present with chest pain, hemoptysis, tachypnea, tachycardia, and respiratory alkalosis should be particularly screened for PE.

The Accuracy of Tidal Volume Measured With a Smart Shirt During Tasks of Daily Living in Healthy Subjects: Cross-sectional Study

Background

The Hexoskin is a smart shirt that can take continuous and objective measurements and could be part of a potential telemonitoring system.

Objective

The aim of this study was to determine the accuracy of the calibrated Hexoskin in measuring tidal volumes (TVs) in comparison to spirometry during various tasks.

Methods

In a cross-sectional study, the TV of 15 healthy subjects was measured while performing seven tasks using spirometry and the Hexoskin. These tasks were performed during two sessions; between sessions, all equipment was removed. A one-time spirometer-based calibration per task was determined in session 1 and applied to the corresponding task in both sessions. Bland-Altman analysis was used to determine the agreement between TV that was measured with the Hexoskin and that measured with spirometry. A priori, we determined that the bias had to be less than ±5%, with limits of agreement (LOA) of less than ±15%. Lung volumes were measured and had to have LOA of less than ±0.150 L.

Results

In the first session, all tasks had a median bias within the criteria (±0.6%). In the second session, biases were ±8.9%; only two tasks met the criteria. In both sessions, LOA were within the criteria in six out of seven tasks (±14.7%). LOA of lung volumes were greater than 0.150 L.

Conclusions

The Hexoskin was able to correctly measure TV in healthy subjects during various tasks. However, after reapplication of the equipment, calibration factors were not able to be reused to obtain results within the determined boundaries.

Trial Registration

Netherlands Trial Register NL6934; https://www.trialregister.nl/trial/6934

ROSE: radiology, obstruction, symptoms and exposure - a Delphi consensus definition of the association of COPD and bronchiectasis by the EMBARC Airways Working Group

INTRODUCTION

The coexistence of COPD and bronchiectasis seems to be common and associated with a worse prognosis than for either disease individually. However, no definition of this association exists to guide researchers and clinicians.

METHODS

We conducted a Delphi survey involving expert pulmonologists and radiologists from Europe, Turkey and Israel in order to define the "COPD- [bronchiectasis] BE association".A panel of 16 experts from EMBARC selected 35 statements for the survey after reviewing scientific literature. Invited participants, selected on the basis of expertise, geographical and sex distribution, were asked to express agreement on the statements. Consensus was defined as a score of ≥6 points (scale 0 to 9) in ≥70% of answers across two scoring rounds.

RESULTS

102 (72.3%) out of 141 invited experts participated in the first round. Their response rate in the second round was 81%. The final consensus definition of "COPD-BE association" was: "The coexistence of (1) specific radiological findings (abnormal bronchial dilatation, airways visible within 1 cm of pleura and/or lack of tapering sign in ≥1 pulmonary segment and in >1 lobe) with (2) an obstructive pattern on spirometry ([forced expiratory volume in 1 s] FEV1/[forced vital capacity] FVC <0.7), (3) at least two characteristic symptoms (cough, expectoration, dyspnoea, fatigue, frequent infections) and (4) current or past exposure to smoke (≥10 pack-years) or other toxic agents (biomass, etc.)". These criteria form the acronym "ROSE" (Radiology, Obstruction, Symptoms, Exposure).

CONCLUSIONS

The Delphi process formulated a European consensus definition of "COPD-BE association". We hope this definition will have broad applicability across clinical practice and research in the future.

Multidimensional indices in the assessment of chronic obstructive pulmonary disease

Chronic obstructive pulmonary disease (COPD), a very common disease, is the third leading cause of death worldwide. Due to the significant heterogeneity of clinical phenotypes of COPD there is no single method suitable for predicting patients' health status and outcomes, and therefore multidimensional indices, assessing different components of the disease, were developed and are recommended for clinical practice by international guidelines. Several indices have been widely accepted: BODE and its modifications, ADO, DOSE, CODEX, COTE. They differ in their composition and aim, while they are more accurate and better validated in specific settings and populations. We review the characteristics, strengths and limitations of these indices, and we discuss their role in routine management of patients with COPD, as well as in specific clinical scenarios, such as resuscitation and ceiling of care, or decisions to offer more invasive treatments. This analysis may help clinicians to use those indexes in a more practical and appropriate way.

Serum MCP-1 and NGAL Play an Important Role in the Acute Inflammatory Event of Chronic Obstructive Pulmonary Disease

NGAL is mainly secreted by neutrophils which play the core role in AECOPD. MCP-1 is secreted specifically by monocytes and macrophages. Both biomarkers are involved in the core process of acute inflammatory reaction in COPD. So We analyzed serum NGAL and MCP-1levels to explore their potential clinical values in the chronic obstructive pulmonary disease (COPD) .This study enrolled 97 COPD patients and 50 healthy controls. All participants received blood collection and lung function test and arterial blood gas measurements. The expression levels of serum NGAL and MCP-1 were measured by ELISA. The serum NGAL and MCP-1 levels of COPD with community-acquired pneumonia (COPD-CAP) patients were significantly higher than those of acute exacerbation of chronic obstructive pulmonary disease (AECOPD) patients and healthy adults. The NGAL levels of the GOLD III and IV groups were significantly higher than those of the GOLD II group. Spearman correlation analysis showed a negative correlation between NGAL and FEV1%pred, FVC% pred. ROC curves indicated that NGAL has a high diagnostic value for both AECOPD and COPD-CAP. NGAL has the value of distinguishing GOLD I and II from GOLD III and IV. MCP-1 have moderate diagnostic value for COPD-CAP and can differentiate COPD-CAP from AECOPD. This study shows NGAL has certain diagnostic value for AECOPD and COPD-CAP, but can not distinguish the two. NGAL is closely related to airway remodeling and can be used as a potential indicator to distinguish the higher GOLD degree. MCP-1 can be used as potential indicator for the diagnosis of COPD-CAP.

Sputum Gene Expression Reveals Dysregulation of Mast Cells and Basophils in Eosinophilic COPD

Purpose

The clinical and inflammatory associations of mast cells (MCs) and basophils in chronic obstructive pulmonary disease (COPD) are poorly understood. We previously developed and validated a qPCR-based MC/basophil gene signature in asthma to measure these cells in sputum samples. Here, we measured this gene signature in a COPD and control population to explore the relationship of sputum MCs/basophils to inflammatory and COPD clinical characteristics.

Patients and Methods

MC/basophil signature genes (TPSAB1/TPSB2, CPA3, ENO2, GATA2, KIT, GPR56, HDC, SOCS2) were measured by qPCR in sputum from a COPD (n=96) and a non-respiratory control (n=17) population. Comparative analyses of gene expression between the COPD and the control population, and between eosinophilic COPD and non-eosinophilic COPD were tested. Logistic regression analysis and Spearman correlation were used to determine relationships of sputum MC/basophil genes to inflammatory (sputum eosinophil proportions, blood eosinophils) and clinical (age, body mass index, quality of life, lung function, past year exacerbations) characteristics of COPD.

Results

MC/basophil genes were increased in COPD versus control participants (CPA3, KIT, GATA2, HDC) and between eosinophilic-COPD and non-eosinophilic COPD (TPSB2, CPA3, HDC, SOCS2). We found all MC/basophil genes were positively intercorrelated. In COPD, MC/basophil genes were associated with eosinophilic airway inflammation (GATA2, TPSB2, CPA3, GPR56, HDC, SOCS2), blood eosinophilia (all genes) and decreased lung function (KIT, GATA2, GPR56, HDC).

Conclusion

We demonstrate associations of MCs and basophils with eosinophilic inflammation and lower lung function in COPD. These findings are consistent with prior results in asthma and may represent a new tool for endotyping eosinophilic-COPD.

Nemiralisib in Patients with an Acute Exacerbation of COPD: Placebo-Controlled, Dose-Ranging Study

Background

Management of acute exacerbations of chronic obstructive pulmonary disease (COPD) is sometimes inadequate leading to either prolonged duration and/or an increased risk of recurrent exacerbations in the period following the initial event.

Objective

To evaluate the safety and efficacy of inhaled nemiralisib, a phosphoinositide 3-kinase δ inhibitor, in patients experiencing an acute exacerbation of COPD.

Patients and Methods

In this double-blind, placebo-controlled study, COPD patients (40-80 years, ≥10 pack-year smoking history, current moderate/severe acute exacerbation of COPD requiring standard-of-care treatment) were randomized to placebo or nemiralisib 12.5 µg, 50 µg, 100 µg, 250 µg, 500 µg, or 750 µg (ratio of 3:1:1:1:1:1:3; N=938) for 12 weeks with an exploratory 12-week follow-up period. The primary endpoint was change from baseline in post-bronchodilator FEV1 at week 12. Key secondary endpoints were rate of re-exacerbations, patient-reported outcomes (Exacerbations of Chronic Pulmonary Disease Tool, COPD Assessment Test, St George's Respiratory Questionnaire-COPD), plasma pharmacokinetics (PK) and safety/tolerability.

Results

There was no difference in change from baseline FEV1 at week 12 between the nemiralisib and placebo treatment groups (posterior adjusted median difference, nemiralisib 750 µg and placebo: -0.004L (95% CrI: -0.051L to 0.042L)). Overall, there were also no differences between nemiralisib and placebo in secondary endpoints, including re-exacerbations. Plasma PK increased in a dose proportional manner. The most common adverse event for nemiralisib was post-inhalation cough which appeared to be dose-related.

Conclusion

The addition of nemiralisib to standard-of-care treatment for 12 weeks did not improve lung function or re-exacerbations in patients with, and following an acute exacerbation of COPD. However, this study demonstrated that large clinical trials recruiting acutely exacerbating patients can successfully be conducted.

Protein Biomarkers for COPD Outcomes

COPD is a clinically heterogeneous syndrome characterized by injury to airways, airspaces, and lung vasculature and usually caused by tobacco smoke and/or air pollution exposure. COPD is also independently associated with nonpulmonary comorbidities (eg, cardiovascular disease) and malignancies (eg, GI, bladder), suggesting a role for systemic injury. Since not all those with exposure develop COPD, there has been a search for plasma and lung biomarkers that confer increased cross-sectional and longitudinal risk. This search typically focuses on clinically relevant COPD outcomes such as FEV1, FEV1 decline, CT measurements of emphysema, or exacerbation frequency. The rapid advances in omics technology and the molecular phenotyping of COPD cohorts now permit large-scale evaluation of genetic, transcriptomic, proteomic, and metabolic biomarkers. This review focuses on protein biomarkers associated with clinically relevant COPD outcomes. The prototypic COPD protein biomarker is alpha-1 antitrypsin; however, this biomarker only accounts for 1% to 5% of COPD. This article reviews and summarizes the evidence for other validated biomarkers for each COPD outcome, and discusses their advantages, weaknesses, and required regulatory steps to move the biomarker from the bench into clinic. Although we highlight the emergence of many novel biomarkers (eg, fibrinogen, soluble receptor for advanced glycation, surfactant protein D, club cell secretory protein), there is increasing evidence that individual biomarkers only explain a fraction of the increased COPD risk and that multiple biomarker panels are needed to completely explain clinical variation and risk in individuals and populations.

Association of serum vitamin D levels with disease severity, systemic inflammation, prior lung function loss and exacerbations in a cohort of patients with chronic obstructive pulmonary disease (COPD)

Background

Vitamin D deficiency has been associated with chronic disorders including chronic obstructive pulmonary disease (COPD) but the relationships with inflammation, exacerbations and disease progression remain unclear.

Methods

In this monocentric cross-sectional observational study we analyzed the disease status, systemic inflammation, prior exacerbation frequency and loss in lung function in relation to serum 25-hydroxyvitamin D (25-OHD) levels in a cohort of 94 patients with COPD. Serum 25-OHD, C-reactive protein, interleukin-6 and tumor necrosis factor-α were quantified. Exacerbation frequencies and sunlight exposure were assessed. These parameters were analyzed in correlation to the current forced expiratory volume in 1 s (FEV₁), the individual average 3-year FEV₁ decline and the Global Initiative for Chronic Obstructive Lung Disease (GOLD) stage.

Results

We observed fair correlation between serum 25-OHD and the current FEV₁ (r=0.38, P<0.001). Furthermore, mean serum 25-OHD was significantly altered between patients of GOLD stages I–IV (P=0.013). There was weak negative correlation of 25-OHD and the average annual change of the FEV₁ (r=−0.26, P<0.05). Furthermore, we observed fair negative correlation between 25-OHD and C-reactive protein (r=−0.32, P<0.01) as well as weak negative correlation with interleukin-6 (r=−0.23, P<0.05). While the exacerbation frequency significantly differed between GOLD stages (P=0.04), there was no direct association between exacerbations and 25-OHD levels.

Conclusion

Our data confirm frequent vitamin D deficiency in COPD and point out correlations between 25-OHD levels, systemic inflammation, disease severity and progression.

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.

Defective monocyte-derived macrophage phagocytosis is associated with exacerbation frequency in COPD

BACKGROUND

Lower airway bacterial colonisation (LABC) in COPD patients is associated with increased exacerbation frequency and faster lung function decline. Defective macrophage phagocytosis in COPD drives inflammation, but how defective macrophage function contributes to exacerbations is not clear. This study investigated the association between macrophage phagocytosis and exacerbation frequency, LABC and clinical parameters.

METHODS

Monocyte-derived macrophages (MDM) were generated from 92 stable COPD patients, and at the onset of exacerbation in 39 patients. Macrophages were exposed to fluorescently labelled Haemophilus influenzae or Streptococcus pneumoniae for 4 h, then phagocytosis measured by fluorimetry and cytokine release by ELISA. Sputum bacterial colonisation was measured by PCR.

RESULTS

Phagocytosis of H. influenzae was negatively correlated with exacerbation frequency (r = 0.440, p < 0.01), and was significantly reduced in frequent vs. infrequent exacerbators (1.9 × 10³ RFU vs. 2.5 × 10³ RFU, p < 0.01). There was no correlation for S. pneumoniae. There was no association between phagocytosis of either bacteria with age, lung function, smoking history or treatment with inhaled corticosteroids, or long-acting bronchodilators. Phagocytosis was not altered during an exacerbation, or in the 2 weeks post-exacerbation. In response to phagocytosis, MDM from exacerbating patients showed increased release of CXCL-8 (p < 0.001) and TNFα (p < 0.01) compared to stable state.

CONCLUSION

Impaired COPD macrophage phagocytosis of H. influenzae, but not S. pneumoniae is associated with exacerbation frequency, resulting in pro-inflammatory macrophages that may contribute to disease progression. Targeting these frequent exacerbators with drugs that improve macrophage phagocytosis may prove beneficial.

The different phenotypes of COPD

BACKGROUND

Chronic obstructive pulmonary disease (COPD) is associated with significant morbidity and mortality. To improve the health status and reduce symptom burden, it is important to identify a group of patients with similar characteristics and prognosis, called clinical phenotypes. Herein we shall review the different phenotypes of COPD.

SOURCES OF DATA

Keywords (COPD, phenotype, acute exacerbation) search was conducted in PubMed, Google Scholar.

AREAS OF AGREEMENT

Those with raised blood eosinophil counts respond better to steroid therapy at stable state and exacerbation.

AREAS OF CONTROVERSY

There is no universally accepted blood eosinophil cut-off value that will indicate favourable response to corticosteroids and potentially for future biologic therapy.

GROWING POINTS

There is an urgent need for further therapeutic options for COPD patients with non-eosinophilic inflammation.

AREAS TIMELY FOR DEVELOPING RESEARCH

Well-designed COPD trials with identification of phenotypes for more personalization of the treatment of COPD.

Characteristics of Pulmonary Rehabilitation Programs Following an Exacerbation of Chronic Obstructive Pulmonary Disease: A SYSTEMATIC REVIEW

PURPOSE

Early pulmonary rehabilitation (PR) has beneficial impacts on people with chronic obstructive pulmonary disease (COPD) when delivered after an exacerbation; however, program characteristics are diverse. This systematic review aimed to determine the impact of PR program characteristics (mode, length, commencement, frequency, location, and supervision) on clinical outcomes following an exacerbation of COPD.

METHODS

Studies were screened from Medline, Medline in progress, Embase, CINAHL, SCOPUS, CENTRAL, and PEDro. Included studies were randomized controlled trials of early PR after an exacerbation of COPD (commenced during hospital stay or ≤4 wk of hospital discharge). The primary outcomes were hospital readmissions and mortality.

RESULTS

Thirty studies were included. Exercise training alone was delivered in 43% of studies. Program duration varied from length of inpatient stay to 12 wk. The interventions commenced as early as ≤24 hr of hospitalization for acute exacerbation, and up to 2 wk after discharge. Early PR was compared to usual care, and no studies made a direct comparison of the program characteristics of interest. Program characteristics associated with reduced risk of hospital admission were commencement after hospital discharge, duration longer than 3 wk, and programs that included exercise training and education (relative risk of readmission range 0.6-0.79); however, it was not possible to determine which of these characteristics made the most important contribution. Mortality risk did not vary according to PR program characteristics.

CONCLUSION

Programs >3 wk, started after hospital discharge or including an educational component in addition to exercise, were most effective at reducing hospital readmissions.

Pneumonia Is Associated with Increased Mortality in Hospitalized COPD Patients: A Systematic Review and Meta-Analysis

BACKGROUND

Patients with chronic obstructive pulmonary disease (COPD) are at a heightened risk of pneumonia. Whether coexisting community-acquired pneumonia (CAP) can predict increased mortality in hospitalized COPD patients is still controversial.

OBJECTIVE

This systematic review and meta-analysis aims to assess the association between CAP and mortality and morbidity in COPD patients hospitalized for acute worsening of respiratory symptoms.

METHODS

In this review, cohort studies and case-control studies investigating the impact of CAP in hospitalized COPD patients were retrieved from 4 electronic databases from inception until December 2019. Methodological quality of included studies was assessed using Newcastle-Ottawa Quality Assessment Scale. The primary outcome was mortality. The secondary outcomes included length of hospital stay, need for mechanical ventilation, intensive care unit (ICU) admission, length of ICU stay, and readmission rate. The Mantel-Haenszel method and inverse variance method were used to calculate pooled relative risk (RR) and mean difference (MD), respectively.

RESULTS

A total of 18 studies were included. The presence of CAP was associated with higher mortality (RR = 1.85; 95% CI: 1.50-2.30; p < 0.00001), longer length of hospital stay (MD = 1.89; 95% CI: 1.19-2.59; p < 0.00001), more need for mechanical ventilation (RR = 1.48; 95% CI: 1.32-1.67; p < 0.00001), and more ICU admissions (RR = 1.58; 95% CI: 1.24-2.03; p = 0.0002) in hospitalized COPD patients. CAP was not associated with longer ICU stay (MD = 5.2; 95% CI: -2.35 to 12.74; p = 0.18) or higher readmission rate (RR = 1.02; 95% CI: 0.96-1.09; p = 0.47).

CONCLUSION

Coexisting CAP may be associated with increased mortality and morbidity in hospitalized COPD patients, so radiological confirmation of CAP should be required and more attention should be paid to these patients.

Assessment and treatment of airflow obstruction in patients with chronic obstructive pulmonary disorder: a guide for the clinician

Introduction: Chronic obstructive pulmonary disorder (COPD) is a common cause of disability, morbidity and mortality worldwide. Early diagnosis and adequate treatment maintained over time are crucial to reducing these harmful consequences.Areas covered Persistent, not reversible and naturally progressive airflow obstruction is the functional hallmark of COPD. Therefore, in the presence of individual and environmental risk factors, with or without reported suggestive symptoms, simple spirometry must be performed enough quickly to objectify an obstructive ventilatory defect and assist physicians in making a diagnosis of COPD. Then, to cope with the heterogeneity of COPD patients, more specific functional tests and imaging techniques should be implemented to better define the underlying prevalent disease and its severity. That is necessary to decide whether to introduce ICS and establish the initial level of the treatment with just one or two bronchodilators, to control and freeze, when possible, the underlying pathological process.Expert opinion: The objective assessment of airflow obstruction is mandatory to make a diagnosis of COPD, but the prevalent disease sustaining the disorder should also be investigated to select a targeted therapy, because main determinants of airflow obstruction can be different in COPD patients and may differently respond to treatment.

Active screening for COPD among hospitalized smokers - a feasibility study

BACKGROUND

Spirometry is a primary tool for early chronic obstructive pulmonary disease (COPD) detection in patients with risk factors, for example, cigarette smoking. The aim of this study was to evaluate the strategy of an active screening for COPD among smokers admitted to the pulmonary and cardiology department.

METHODS

This prospective study was conducted between February and March 2019. All hospitalized smokers aged 40 years and older completed an original questionnaire and had spirometry measurement with a bronchial reversibility test (if applicable) performed by medical students using a portable spirometer.

RESULTS

One hundred and eighty-eight patients were eligible to participate in the study. Seventy (37%) subjects refused to participate. Eventually, 116 (62%) patients were included in the final analysis and 94 (81%) performed spirometry correctly. In total, 32 (34 %) patients were found to have COPD. Nine (28%) of these patients were newly diagnosed, 89% of them had mild-to-moderate airway obstruction. Patients with newly diagnosed COPD were significantly younger [age 63 (56-64) versus 69 (64-78) years], had a longer smoking-free period [17 (13-20) versus 9 (2-12) years], had fewer symptoms and had a better lung function compared with patients with a previous diagnosis of COPD (p < 0.05 for all comparisons).

CONCLUSION

The proposed diagnostic strategy can be successfully used to improve COPD detection in the inpatient setting. The majority of the newly diagnosed COPD patients had mild-to-moderate airway obstruction. Patients who should be particularly screened for COPD include ex-smokers with less pronounced respiratory symptoms.

Interrelationships Among Small Airways Dysfunction, Neutrophilic Inflammation, and Exacerbation Frequency in COPD

BACKGROUND

Small airways disease (SAD) is a key component of COPD and is a main contributing factor to lung function decline.

RESEARCH QUESTION

Is SAD a key feature of frequent COPD exacerbators and is this related to airway inflammation?

STUDY DESIGN AND METHODS

Thirty-nine COPD patients defined as either frequent exacerbator (FE) group (≥ 2 exacerbations/y; n = 17) and infrequent exacerbator (IFE) group (≤ 1 exacerbation/y; n = 22) underwent the forced oscillation technique (resistance at 5 Hz minus 19 Hz [R5-R19], area of reactance [AX]), multiple breath nitrogen washout (conducting airways ventilation heterogeneity, acinar ventilation heterogeneity [S_acin]), plethysmography (ratio of residual volume to total lung capacity), single-breath transfer factor of the lung for carbon monoxide, spirometry (FEV₁, FEV₁/FVC), and paired inspiratory-expiratory CT scans to ascertain SAD. A subpopulation underwent bronchoscopy to enable enumeration of BAL cell proportions.

RESULTS

S_acin was significantly higher in the COPD FE group compared with the IFE group (P = .027). In the FE group, markers of SAD were associated strongly with BAL neutrophil proportions, R5-R19 (P = .001, r = 0.795), AX (P = .049, ρ = 0.560), residual volume to total lung capacity ratio (P = .004, r = 0.730), and the mean lung density of the paired CT scans (P = .018, r = 0.639).

INTERPRETATION

Increased S_acin may be a consequence of previous exacerbations or may highlight a group of patients prone to exacerbations. Measures of SAD were associated strongly with neutrophilic inflammation in the small airways of FE patients, supporting the hypothesis that frequent exacerbations are associated with SAD related to increased cellular inflammation.

Advances in understanding of mechanisms related to increased cardiovascular risk in COPD

INTRODUCTION

Chronic obstructive pulmonary disease (COPD) represents a serious global health issue that is commonly associated with cardiovascular (CV) disease (CVD). The close relationship between COPD and CVD could be explained by different factors, first and foremost a chronic low-grade systemic inflammation implicated in the pathogenesis of both diseases and several stimuli enhancing the inflammatory processes and causing a mixed condition with worse outcomes than either disorder alone.

AREAS COVERED

The present narrative review considers the mechanisms underlying the increased CV risk in COPD, and it provides insights on biomarkers and predictive models to predict CVD in COPD patients.

EXPERT OPINION

COPD patients often remain asymptomatic of CVD, with respiratory symptoms generally attributed to the preexisting pulmonary disease. It is fundamental to understand the mechanistic pathways that underpin the intimate relationship between the two disorders. However, it is still not clear what is the origin of the common background of low-grade systemic inflammation, it could be a 'spillover' or a general inflammatory state. Primary prevention, cross-collaboration between specialists and early detection via predictive biomarkers and validated models are fundamental to stratify COPD patients according to CV risk.

Management of chronic obstructive pulmonary disease: A review focusing on exacerbations

Purpose

Chronic obstructive pulmonary disease (COPD) is a significant cause of morbidity and mortality in the United States. Exacerbations— acute worsening of COPD symptoms—can be mild to severe in nature. Increased healthcare resource use is common among patients with frequent exacerbations, and exacerbations are a major cause of the high 30-day hospital readmission rates associated with COPD.

Summary

This review provides a concise overview of the literature regarding the impact of COPD exacerbations on both the patient and the healthcare system, the recommendations for pharmacologic management of COPD, and the strategies employed to improve patient care and reduce hospitalizations and readmissions. COPD exacerbations significantly impact patients’ health-related quality of life and disease progression; healthcare costs associated with severe exacerbation-related hospitalization range from $7,000 to $39,200. Timely and appropriate maintenance pharmacotherapy, particularly dual bronchodilators for maximizing bronchodilation, can significantly reduce exacerbations in patients with COPD. Additionally, multidisciplinary disease-management programs include pulmonary rehabilitation, follow-up appointments, aftercare, inhaler training, and patient education that can reduce hospitalizations and readmissions for patients with COPD.

Conclusion

Maximizing bronchodilation by the appropriate use of maintenance therapy, together with multidisciplinary disease-management and patient education programs, offers opportunities to reduce exacerbations, hospitalizations, and readmissions for patients with COPD.

Proton pump inhibitors for chronic obstructive pulmonary disease

BACKGROUND

Chronic obstructive pulmonary disease (COPD) is a common and progressive disease characterised by chronic cough, airflow limitation and recurrent exacerbations. Since COPD exacerbations are linked to rising mortality and reduced quality of life, the condition poses a substantial burden on individuals, society and the healthcare system. Effective management of COPD exacerbations that includes treatment of related conditions in people with COPD is thus recognised as a relevant clinical question and an important research topic. Gastroesophageal reflux disease (GERD) is a known comorbidity of COPD, and pulmonary microaspiration of gastric acid is thought to be a possible cause of COPD exacerbations. Therefore, reducing gastric acid secretion may lead to a reduction in COPD exacerbations. Proton pump inhibitors (PPIs) are one of the most commonly prescribed medications and are recommended as first-line therapy for people with GERD because of their inhibitory effects on gastric acid secretion. Treatment with PPIs may present a viable treatment option for people with COPD.

OBJECTIVES

To evaluate the efficacy and safety of PPI administration for people with COPD, focusing on COPD-specific outcomes.

SEARCH METHODS

We searched the Cochrane Airways Register of Trials and conventional clinical trial registers from inception to 22 May 2020. We also screened bibliographies of relevant studies.

SELECTION CRITERIA

Parallel-group and cluster-randomised controlled trials (RCTs) that compared oral PPIs versus placebo, usual care or low-dose PPIs in adults with COPD were eligible for inclusion. We excluded cross-over RCTs, as well as studies with a duration of less than two months.

DATA COLLECTION AND ANALYSIS

Two independent review authors screened search results, selected studies for inclusion, extracted study characteristics and outcome data, and assessed risk of bias according to standard Cochrane methodology. We resolved discrepancies by involving a third review author. Primary outcomes of interest were COPD exacerbations, pneumonia and other serious adverse events. Secondary outcomes were quality of life, lung function test indices, acute respiratory infections and disease-specific adverse events. We extracted data on these outcome measures and entered into them into Review Manager software for analysis.

MAIN RESULTS

The search identified 99 records, and we included one multicentre RCT that randomised 103 adults with COPD. The 12-month RCT compared an oral PPI (lansoprazole) and usual care versus usual care alone. It was conducted at one tertiary care hospital and three secondary care hospitals in Japan. This study recruited participants with a mean age of 75 years, and excluded people with symptoms or history of GERD. No placebo was used in the usual care arm. Among the primary and secondary outcomes of this review, the study only reported data on COPD exacerbations and acute respiratory infections (the common cold). As we only included one study, we could not conduct a meta-analysis. The included study reported that 12 of the 50 people on lansoprazole had at least one exacerbation over a year, compared to 26 out of 50 on usual care (risk ratio 0.46, 95% CI 0.26 to 0.81). The frequency of COPD exacerbations per person in a year was also lower in the PPI plus usual care group than in the usual care alone group（0.34 ± 0.72 vs 1.18 ± 1.40; P < 0.001). The number of people with at least one cold over the year was similar in both groups: 26 people on lansoprazole and 27 people in the usual care group. We judged the evidence to be of low to very low certainty, according to GRADE criteria. The study reported no data on pneumonia and other serious adverse events, quality of life, lung function test indices or disease-specific adverse events. The risk of bias was largely low or unclear for the majority of domains, though the performance bias was a high risk, as the study was not blinded.

AUTHORS' CONCLUSIONS

Evidence identified by this review is insufficient to determine whether treatment with PPIs is a potential option for COPD. The sample size of the included trial is small, and the evidence is low to very low-certainty. The efficacy and safety profile of PPIs for people with COPD remains uncertain. Future large-scale, high-quality studies are warranted, which investigate major clinical outcomes such as COPD exacerbation rate, serious adverse events and quality of life.

Comorbidities and Readmissions in Survivors of Acute Hypercapnic Respiratory Failure

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

A Refined View of Airway Microbiome in Chronic Obstructive Pulmonary Disease at Species and Strain-Levels

Little is known about the underlying airway microbiome diversity in chronic obstructive pulmonary disease (COPD) at in-depth taxonomic levels. Here we present the first insights on the COPD airway microbiome at species and strain-levels. The full-length 16S rRNA gene was characterized from sputum in 98 COPD patients and 27 age-matched healthy controls, using the Pacific Biosciences sequencing platform. Individual species within the same genus exhibited reciprocal relationships with COPD and disease severity. Species dominant in health can be taken over by another species within the same genus but with potentially increasing pathogenicity in severe COPD patients. Ralstonia mannitolilytica, an opportunistic pathogen, was significantly increased in frequent exacerbators (fold-change = 4.94, FDR P = 0.005). There were distinct patterns of interaction between bacterial species and host inflammatory mediators according to neutrophilic or eosinophilic inflammations, two major airway inflammatory phenotypes in COPD. Haemophilus influenzae, Moraxella catarrhalis, Pseudomonas aeruginosa, and Neisseria meningitidis were associated with enhanced Th1, Th17 and pro-inflammatory mediators, while a group of seven species including Tropheryma whipplei were specifically associated with Th2 mediators related to eosinophilia. We developed an automated pipeline to assign strain-level taxonomy leveraging bacterial intra-genomic 16S allele frequency. Using this pipeline we further resolved three non-typeable H. influenzae strains PittEE, PittGG and 86-028NP with reasonable precision and uncovered strain-level variation related to airway inflammation. In particular, 86-028NP and PittGG strains exhibited inverse associations with Th2 chemokines CCL17 and CCL13, suggesting their abundances may inversely predict eosinophilic inflammation. A systematic comparison of 16S hypervariable regions indicated V1V3 instead of the commonly used V4 region was the best surrogate for airway microbiome. The full-length 16S data augmented the power of functional inference, which slightly better recapitulated the actual metagenomes. This led to the unique identification of butyrate-producing and nitrate reduction pathways as depleted in COPD. Our analysis uncovered finer-scale airway microbial diversity that was previously underappreciated, thus enabled a refined view of the airway microbiome in COPD.

Detection of Cell-Dissociated Non-Typeable Haemophilus influenzae in the Airways of Patients with Chronic Obstructive Pulmonary Disease

Background

Non-typeable Haemophilus influenzae (NTHi) is the most commonly found pathogen in the lower respiratory airways of patients with COPD. NTHi is predominantly regarded as an intracellular pathogen; however, like most pathogens, it can exist and co-exist in two broad forms: cell-associated (intracellularly or adhered to cells) or cell-dissociated (biofilm dispersed or planktonic). We sought to investigate if cell-dissociated NTHi can be detected from the sputum of COPD patients and assess this relationship to disease severity and airway inflammation.

Methods

DNA was extracted from the sputum plug and cell-free supernatant to quantify absolute (cell-associated and cell-dissociated NTHi) and cell-dissociated NTHi, respectively, from 87 COPD subjects attending an observational longitudinal COPD exacerbation study. NTHi was quantified using TaqMan hydrolysis probes, targeting the OMP P6 gene using qPCR.

Results

At stable state cell-dissociated NTHi was detected 56% of subjects with a median (IQR) of 9.95x10² gene copies (1.26x10² to 1.90x10⁴). Cell-dissociated NTHi correlated with absolute NTHi levels (r=0.34, p<0.01) but not airway inflammation or spirometry at stable state. At exacerbation, cell-dissociated NTHi correlated with lung function (FEV₁ r=0.629, p=0.005; FEV₁%predicted r=0.564, p=0.015; FVC r=0.476 p=0.046) and sputum neutrophilic inflammation (% neutrophils r=0.688, p=0.002; total neutrophils r=0.518, p=0.028).

Conclusion

In patients with COPD, NTHi can exist in both cell-associated and cell-dissociated forms. Cell-dissociated NTHi is associated with neutrophilic airway inflammation during exacerbations of COPD and may be a driving factor in worsening lung function during these episodes.