Definition and Nomenclature of Chronic Obstructive Pulmonary Disease: Time for Its Revision

An Update on Outcomes for COPD Pharmacological Trials: A COPD Investigators Report - Reassessment of the 2008 American Thoracic Society/European Respiratory Society Statement on Outcomes for COPD Pharmacological Trials

Background: In 2008, a dedicated American Thoracic Society/European Respiratory Society task force published a paper on the possible use and limitations of clinical outcomes and biomarkers to evaluate the impact of pharmacological therapy in patients with chronic obstructive pulmonary disease. Since then, our scientific understanding of chronic obstructive pulmonary disease has increased considerably; there has been a progressive shift from a one-size-fits-all diagnostic and therapeutic approach to a personalized approach; and many new treatments currently in development will require new endpoints to evaluate their efficacy adequately. Objectives: The emergence of several new relevant outcome measures motivated the authors to review advances in the field and highlight the need to update the content of the original report. Methods: The authors separately created search strategies for the literature, primarily based on their opinions and assessments supported by carefully chosen references. No centralized examination of the literature or uniform criteria for including or excluding evidence were used. Measurements and Main Results: Endpoints, outcomes, and biomarkers have been revisited. The limitations of some of those reported in the American Thoracic Society/European Respiratory Society task force document have been highlighted. In addition, new tools that may be useful, especially in evaluating personalized therapy, have been described. Conclusions: Because the "label-free" treatable traits approach is becoming an important step toward precision medicine, future clinical trials should focus on highly prevalent treatable traits, and this will influence the choice of outcomes and markers to be considered. The use of the new tools, particularly combination endpoints, could help better identify the right patients to be treated with the new drugs.

Assessment of Noninvasive Oxygen Saturation in Patients With COPD During Pulmonary Rehabilitation: Smartwatch versus Pulse Oximeter

BACKGROUND

Patients with COPD can have hypoxemia; hence, monitoring peripheral SpO2 during pulmonary rehabilitation is recommended. This study aimed to examine the accuracy of SpO2 readings in patients with COPD as measured by wearable devices at rest and after physical exercise.

METHODS

Thirty-six participants with COPD (20 women), ages 52-89 years, participated in this cross-sectional study. Oxygen saturation was concurrently measured by using the Contec Pulse Oximeter CMS50D as a comparator, and the Apple Watch Series 7 and the Garmin Vivosmart 4 at rest and immediately after the 30-s sit-to-stand test and the 6-min walk test (6MWT).

RESULTS

For the Apple Watch, the root mean squared error showed a deviation of 3.5% at rest, 4.1% after the 30-s sit-to-stand test, and 3.9% after the 6MWT. The level of agreement was 2.8 ± 2.4 (7.6, -1.9) at rest, 3.1 ± 2.8 (8.6, -2.3) after the 30-s sit-to-stand test, and 2.8 ± 2.9 (8.6, -2.9) after the 6MWT. For the Garmin Vivosmart, the root mean squared error showed a deviation of 3.3% at rest, 6.1% after the 30-s sit-to-stand test, and 5.4% after the 6MWT. Level of agreement was 1.9 ± 2.7 (7.2, -3.3) at rest, 2.9 ± 5.4 (13.5, -7.7) after the 30-s sit-to-stand test, and 2.3 ± 5.0 (12.1, -7.4) after the 6MWT. The limits of agreement showed considerable measurement variance and a tendency for the devices to be less accurate at lower saturation levels.

CONCLUSIONS

The Apple Watch Series 7 and Garmin Vivosmart 4 overestimated SpO2 in participants with COPD when SpO2 was < 95% and underestimated oxygen saturation when saturation was > 95%. These findings suggest that wearable devices should not be used to monitor oxygen saturation during pulmonary rehabilitation.

Re-exacerbation within 30 days of discharge is associated with poor prognosis in the following year among patients hospitalised with exacerbation of chronic obstructive pulmonary disease: a clinical cohort study

BACKGROUND

Exacerbation of chronic obstructive pulmonary disease (ECOPD) is a complex phenomenon, with marked heterogeneity in the aetiology, pathophysiology and clinical manifestations. This study aimed to evaluate the clinical characteristics and long-term outcomes of patients with 30-day exacerbation among those hospitalised with ECOPD in China.

METHODS

Data from the Acute Exacerbations of Chronic Obstructive Pulmonary Disease Inpatient Registry were used in this study. The patients were divided into re-event and non-event groups based on the incidence of re-exacerbation within 30 days of discharge. Exacerbation, severe exacerbation and all-cause readmissions in the following 12 months were the outcomes of interest. The cumulative incidence rates and incidence densities were calculated. Multivariate hazard function models were used to determine the association between 30-day re-exacerbation and the long-term outcomes after accounting for the competing risk of death.

RESULTS

Re-exacerbation within 30 days of discharge was observed in 4.9% (n=242) of the patients (n=4963). The cumulative incidence rates and incidence densities of exacerbation, severe exacerbation and all-cause readmissions in the event group were significantly higher than those in the non-event group. After adjustment, re-exacerbation within 30 days of discharge was associated with increased risks of exacerbation, severe exacerbation and all-cause readmissions in the following 12 months (adjusted HR: 3.85 (95% CI: 3.09 to 4.80), 3.46 (2.66 to 4.50) and 3.28 (2.52 to 4.25) accordingly).

CONCLUSION

Re-exacerbation of COPD within 30 days of discharge is a significant predictor of long-term prognosis. In clinical practice, short-term re-exacerbation is a significant clinical phenotype of ECOPD that requires careful management at the earliest.

Factors Affecting Development of Chronic Obstructive Pulmonary Disease in Pneumoconiosis Cases: A Cross-sectional Study Between 2017 and 2022 in Turkey

OBJECTIVES

It was aimed to determine the factors affecting the development of chronic obstructive pulmonary disease (COPD) in pneumoconiosis cases.

METHODS

Pneumoconiosis cases were divided into two groups as those with only pneumoconiosis and those with coexistence of pneumoconiosis and COPD. Demographic data, smoking habits, pulmonary function test, radiological findings, and occupational risk factors of the cases were compared.

RESULTS

Chronic obstructive pulmonary disease was detected in 134 of 465 pneumoconiosis cases (28.8%) included in the study. It was determined that patients who developed COPD were statistically significantly older, had longer exposure duration, had lower forced expiratory volume in 1 second, forced vital capacity, and forced expiratory volume in 1 second/forced vital capacity values, and had more pulmonary symptoms. Chronic obstructive pulmonary disease development was more common in sandblasting workers, dental technicians, and miners than in other occupations.

CONCLUSION

It has been shown that the risk of developing COPD is high in cases of pneumoconiosis, independent of smoking, especially in certain occupational groups.

Understanding COPD Etiology, Pathophysiology, and Definition

COPD, one of the leading worldwide health problems, currently lacks truly disease-modifying medical therapies applicable to most patients. Developing such novel therapies has been hampered by the marked heterogeneity of phenotypes between individuals with COPD. Such heterogeneity suggests that, rather than a single cause (particularly just direct inhalation of tobacco products), development and progression of COPD likely involve both complex gene-by-environment interactions to multiple inhalational exposures and a variety of molecular pathways. However, there has been considerable recent progress toward understanding how specific pathological processes can lead to discrete COPD phenotypes, particularly that of small airways disease. Advances in imaging techniques that correlate to specific types of histological damage, and in the immunological mechanisms of lung damage in COPD, hold promise for development of personalized therapies. At the same time, there is growing recognition that the current diagnostic criteria for COPD, based solely on spirometry, exclude large numbers of individuals with very similar disease manifestations. This concise review summarizes current understanding of the etiology and pathophysiology of COPD and provides background explaining the increasing calls to expand the diagnostic criteria used to diagnose COPD and some challenges in doing so.

Should we be screening for COPD? - looking through the lens of lung cancer screening

INTRODUCTION

In May 2022, the US Preventive Services Task Force published their recommendation against screening for chronic obstructive pulmonary disease (COPD) in asymptomatic adults. However, we argue the routine use of spirometry in both asymptomatic and symptomatic high-risk smokers has utility.

AREAS COVERED

We provide published and unpublished observations from a secondary analyses of the American College of Radiology Imaging Network (ACRIN), arm of the National Lung Screening Trial, including 18,463 high-risk current or former smokers who underwent pre-bronchodilator spirometry at baseline. According to history alone, 20% reported a prior diagnosis of 'COPD,' although only 11% (about one half), actually had airflow limitation (Diagnosed COPD) and 9% had Global Initiative for Obstructive Pulmonary Disease GOLD 0 Pre-COPD. Of the remaining 80% of 'asymptomatic' screening participants, 23% had airflow limitation (Screen-detected COPD) and 13% had preserved ratio impaired spirometry (PRISm). This means 45% of this high-risk cohort were reclassified by spirometry, and together with comorbid disease, identified subgroups where lung cancer screening efficacy could be optimized by between 2-6 fold.

EXPERT OPINION

Our preliminary findings suggest lung cancer screening outcomes vary according to 'new' COPD-related spirometric-defined subgroups and that screening spirometry, together with comorbid disease, identifies those for whom lung cancer screening is mostly beneficial or potentially harmful.

Occupational lung disease: when should I think of it and why is it important?

Exposure to toxic inhalants in the workplace has the potential to cause (in susceptible individuals) almost any major type of lung disease, such as asthma, COPD and interstitial lung diseases. Patients with occupational lung disease will often present to or will be managed by respiratory specialists without training in occupational respiratory medicine, and patients (or their clinicians) may not identify a link between their disease and their current or a past job. Without an awareness of the range of different occupational lung diseases that exist, their similarity to their non-occupational counterparts, and without directed questioning, these conditions may go unidentified. Patients with occupational lung diseases are often in lower paid work and are disproportionally affected by health inequality. Both clinical and socioeconomic outcomes generally improve if cases are identified early. This allows appropriate advice to be given about the risks of ongoing exposure, clinical management, occupational mobility and, in some cases, eligibility for legal compensation. As respiratory professionals, it is important that these cases are not missed, and if needed, are discussed with a physician with specialised expertise. Here we describe some of the most common occupational lung diseases and outline the diagnostic and treatment approach.

GOLD 2023 Executive Summary: responses from the GOLD Scientific Committee

We thank the authors of the five letters received in relation to the recent publication of the Global Initiative for Chronic Obstructive Lung Disease (GOLD) 2023 Executive Summary in the European Respiratory Journal [1] for their interest and insightful comments. We address them below, albeit necessarily briefly, under three categories: a global perspective, diagnostic issues, and management of exacerbations.

The GOLD Scientific Committee respond to five letters to the Editor in relation to the GOLD 2023 Executive Summary https://bit.ly/41wJzhk

Cardiovascular Diseases in COPD: From Diagnosis and Prevalence to Therapy

Chronic obstructive pulmonary disease (COPD) is considered one of the leading causes of mortality. Cardiovascular comorbidities are diagnosed often in COPD patients, not only because of the common risk factors these two diseases share, but also because of the systemic inflammation which characterizes COPD and has deleterious effects in the cardiovascular system. The comorbid cardiovascular diseases in COPD result in several difficulties in the holistic treatment of these patients and affect outcomes such as morbidity and mortality. Several studies have reported that mortality from cardiovascular causes is common among COPD patients, while the risk for acute cardiovascular events increases during COPD exacerbations and remains high for a long time even after recovery. In this review, we focus on the prevalence of cardiovascular comorbidities in COPD patients, presenting the evidence regarding the interaction of the pathophysiological pathways which characterize each disease. Furthermore, we summarize information regarding the effects of cardiovascular treatment on COPD outcomes and vice versa. Finally, we present the current evidence regarding the impact of cardiovascular comorbidities on exacerbations, quality of life and survival of COPD patients.

Feasibility, effectiveness and safety of self-management in pulmonary rehabilitation: a study protocol using a hybrid type 1 effectiveness-implementation design

Background

As population ageing accelerates worldwide, chronic diseases will place an increasing burden on society and healthcare systems. Self-management interventions may become a key strategy for addressing chronic disease burden and healthcare costs, also in pulmonary rehabilitation (PR). One of the challenges here is long-term adherence. Understanding the level of adherence to PR may help inform clinical decision-making to focus more on self-management and less on clinical supervision. For this reason, a prediction model (PATCH) was developed. The presented protocol concerns a study that aims 1. to evaluate the safety and effectiveness of self-management within pulmonary rehabilitation (PR) on health outcomes in patients with chronic obstructive pulmonary disease (COPD), 2. to evaluate the predictive validity of the PATCH tool, and 3. to evaluate feasibility and acceptability of self-management and the PATCH tool by patients and physiotherapists.

Methods and analysis

This is a protocol of a hybrid type 1 effectiveness-implementation design, performed in primary physiotherapy practices in The Netherlands. The aim is to include 108 patients with COPD who have already followed PR for at least six weeks (maintenance stage of PR). According to the Dutch KNGF Guideline COPD, physiotherapists should reduce the number of supervised treatments after the maintenance phase and support self-management. In practice, this does not (always) happen. This protocol is based on implementing guideline advice: clinical supervision will be halved but patients are stimulated to engage in self-management by exercising unsupervised, leading to no change in the total planned exercise frequency. During the supervised sessions physiotherapists will assess and stimulate self-management. At baseline, and after 3, 6, 9 and 12 months, health outcomes (including adherence) will be evaluated as the primary outcome of this study. At each measurement, the physiotherapist will decide on the basis of individual scores whether the patient needs more clinical supervision or not. Secondary outcomes are the discriminatory power of the PATCH tool (can patients be correctly classified as adherent or non-adherent), and feasibility and acceptability of self-management and the PATCH tool by patients and physiotherapists. Questionnaires and semi-structured interviews will be used for assessment of the outcomes.Trial registration number: METc 2023/074.

GOLD 2023 Update: Implications for Clinical Practice

In 2022, over 3 million people died of chronic obstructive pulmonary disease (COPD) and the global burden of the disease is expected to increase over the coming decades. Recommendations for the treatment and management of patients with COPD are published by the Global Initiative for Chronic Obstructive Lung Disease, and updated annually with scientific evidence-based recommendations. The 2023 updates, published in November 2022, contain key changes to recommendations for diagnosis and treatment of COPD that are anticipated to have a significant impact on clinical practice for patients with COPD. Updates to how COPD is defined and diagnosed, including the expansion of contributing factors beyond tobacco use, have the potential to lead to the diagnosis of more patients and to allow for the implementation of early interventions for patients during early stages of the disease. Simplification of the treatment algorithms, and placement of triple therapy within these algorithms, will support clinicians in providing appropriate, timely treatment for patients with COPD with a focus on reducing the risk of future exacerbations. Finally, recognition of mortality reduction as a treatment goal in COPD supports an increase in the use of triple therapy, the only pharmacological intervention that has been demonstrated to improve survival for patients with COPD. Although further guidance and clarification are needed in some areas, such as use of blood eosinophil counts in guiding treatment decisions and implementation of treatment protocols following hospitalizations, recent updates to the GOLD recommendations will support clinicians in addressing current gaps in patient care. Clinicians should utilize these recommendations to drive the early diagnosis of patients with COPD, the identification of exacerbations, and the selection of appropriate, timely treatments for patients.

Long-term residential exposure to air pollution and risk of chronic respiratory diseases in Italy: The BIGEPI study

Long-term exposure to air pollution has adverse respiratory health effects. We investigated the cross-sectional relationship between residential exposure to air pollutants and the risk of suffering from chronic respiratory diseases in some Italian cities. In the BIGEPI project, we harmonised questionnaire data from two population-based studies conducted in 2007-2014. By combining self-reported diagnoses, symptoms and medication use, we identified cases of rhinitis (n = 965), asthma (n = 328), chronic bronchitis/chronic obstructive pulmonary disease (CB/COPD, n = 469), and controls (n = 2380) belonging to 13 cohorts from 8 Italian cities (Pavia, Turin, Verona, Terni, Pisa, Ancona, Palermo, Sassari). We derived mean residential concentrations of fine particulate matter (PM₁₀, PM_2.5), nitrogen dioxide (NO₂), and summer ozone (O₃) for the period 2013-2015 using spatiotemporal models at a 1 km resolution. We fitted logistic regression models with controls as reference category, a random-intercept for cohort, and adjusting for sex, age, education, BMI, smoking, and climate. Mean ± SD exposures were 28.7 ± 6.0 μg/m³ (PM₁₀), 20.1 ± 5.6 μg/m³ (PM_2.5), 27.2 ± 9.7 μg/m³ (NO₂), and 70.8 ± 4.2 μg/m³ (summer O₃). The concentrations of PM₁₀, PM_2.5, and NO₂ were higher in Northern Italian cities. We found associations between PM exposure and rhinitis (PM₁₀: OR 1.62, 95%CI: 1.19-2.20 and PM_2.5: OR 1.80, 95%CI: 1.16-2.81, per 10 μg/m³) and between NO₂ exposure and CB/COPD (OR 1.22, 95%CI: 1.07-1.38 per 10 μg/m³), whereas asthma was not related to environmental exposures. Results remained consistent using different adjustment sets, including bi-pollutant models, and after excluding subjects who had changed residential address in the last 5 years. We found novel evidence of association between long-term PM exposure and increased risk of rhinitis, the chronic respiratory disease with the highest prevalence in the general population. Exposure to NO₂, a pollutant characterised by strong oxidative properties, seems to affect mainly CB/COPD.

Combined Pulmonary Fibrosis and Emphysema: When Scylla and Charybdis Ally

Combined pulmonary fibrosis and emphysema (CPFE) is a recently recognized syndrome that, as its name indicates, involves the existence of both interstitial lung fibrosis and emphysema in one individual, and is often accompanied by pulmonary hypertension. This debilitating, progressive condition is most often encountered in males with an extensive smoking history, and is presented by dyspnea, preserved lung volumes, and contrastingly impaired gas exchange capacity. The diagnosis of the disease is based on computed tomography imaging, demonstrating the coexistence of emphysema and interstitial fibrosis in the lungs, which might be of various types and extents, in different areas of the lung and several relative positions to each other. CPFE bears high mortality and to date, specific and efficient treatment options do not exist. In this review, we will summarize current knowledge about the clinical attributes and manifestations of CPFE. Moreover, we will focus on pathophysiological and pathohistological lung phenomena and suspected etiological factors of this disease. Finally, since there is a paucity of preclinical research performed for this particular lung pathology, we will review existing animal studies and provide suggestions for the development of additional in vivo models of CPFE syndrome.

Serum Electrolytes in Patients Presenting With Acute Exacerbation of Chronic Obstructive Pulmonary Disease (COPD) and Their Comparison With Stable COPD Patients

Introduction Chronic obstructive pulmonary disease (COPD) is a major cause of morbidity and mortality, which may be further aggravated by episodes of acute exacerbation of COPD (AECOPD). Electrolyte imbalances during these episodes may add to the duration of hospitalization and disease outcome. Aims and objectives This study aims to compare the serum electrolyte levels of patients with AECOPD and stable COPD and correlate them with the severity of exacerbation and disease outcome. Materials and methods The study was conducted as a case-control study between January 2021 and December 2022. Patients with AECOPD and stable COPD were included as "cases" and "controls," respectively. The various serum electrolyte levels were defined as per recent guidelines. Statistical analysis was performed using SPSS 20.0 (IBM Corp., Armonk, NY). Results A total of 75 patients were included with 41 in the study group and 34 in the control group. The majority of people were between the ages of 61 and 70. The most frequent electrolyte abnormality found was hyponatremia. The mean serum sodium and calcium levels were lower in patients with AECOPD while the mean serum potassium levels were higher. A total of five deaths were recorded in patients with two or more electrolyte imbalances. The latter also had a requirement for home oxygen or non-invasive ventilation at the time of discharge. Conclusion Patients of AECOPD with multiple electrolyte imbalances need scrutinized treatment as they are more prone to develop complications, have poorer outcomes, and prolonged hospital stays.

Female sexual dysfunction in chronic obstructive pulmonary disease

Background

Sexual life of women with chronic obstructive pulmonary disease (COPD) can be affected by breathing difficulties, a decrease in functional status, depressive mood and fatigue.

Objetive

To evaluate the sexual dysfunction in female COPD patients and the possible explanatory mechanisms or correlations between these conditions.

Methods

The study included 70 female patients with COPD aged between 36-65 and 70 age-matched controls. All the subjects completed questionnaires for the Female Sexual Functional Index (FSFI), BECK depression inventory and, spirometry.

Results

Statistically significant sexual dysfunction was noted in COPD patients compared to the non-COPD group (p<0.001). BECK depression inventory scores of the COPD patients were also significantly lower (p<0.001). no correlation between FSFI and BECK depression scores in 'patients' characteristics (r=-0.055, p=0.651). No significant difference was found in age, forced expiratory volume (FEV)1%, and exacerbation history of the previous year according to severity of depression (p>0.005). In linear regression analysis determining depression, no statistically significant factor was found among age, number of comorbidities, and FEV1/ forced vital capacity (FVC) % predicted (p>0.05). In multivariable analysis, only fatigue during intercourse was found to be a statistically significant factor in predicting sexual dysfunction among factors like age, presence of comorbidities, duration of the disease, smoking status, FEV1%, m MRCpoints, 6-minutes walk test, BECK depression scores (p=0.008).

Conclusion

Sexual dysfunction is reported in many COPD females and seems to be related not to spirometric measures or exercise capacity but to fatigue. Depression is also a common comorbidity, of which both disorders are often neglected.

Comparison of treatment persistence, adherence, and risk of exacerbation in patients with COPD treated with single-inhaler versus multiple-inhaler triple therapy: A prospective observational study in China

Aim: This study sought to compare treatment persistence, adherence, and risk of exacerbation among patients with COPD treated with single-inhaler triple therapy (SITT) and multiple-inhaler triple therapy (MITT) in the Chinese population. Methods: This was a multicenter, prospective observational study. Patients with COPD from ten hospitals in Hunan and Guangxi provinces in China were recruited from 1 January 2020 to 31 November 2021 for the study and were followed up for one year. Treatment persistence, adherence, and exacerbation rates during the 12-month follow-up were analyzed in COPD patients treated with SITT and MITT. Results: A total of 1,328 patients were enrolled for final analysis, including 535 (40.3%) patients treated with SITT and 793 (59.7%) treated with MITT. Of these patients, the mean age was 64.9 years and most patients were men. The mean CAT score was 15.2 ± 7.1, and the median (IQR) FEV1% was 54.4 (31.2). The SITT group had a higher mean CAT score, more patients with mMRC >1, and lower mean FEV1% and FEV1/FVC than the MITT patients. Moreover, the proportion of patients with ≥1 exacerbation in the previous year was higher in the SITT cohort. SITT patients had, compared to MITT patients, a higher proportion of adherence (proportion of days covered, PDC) ≥0.8 (86.5% vs. 79.8%; p = 0.006), higher treatment persistence [HR: 1.676 (1.356-2.071), p < 0.001], lower risk of moderate-to-severe exacerbation [HR: 0.729 (0.593-0.898), p = 0.003], and severe exacerbation [HR: 0.675 (0.515-0.875), p = 0.003], as well as reduced all-cause mortality risk [HR: 0.475 (0.237-0.952), p = 0.036] during the 12-month follow-up. Persistence was related to fewer future exacerbations and mortality than non-persistence in the SITT and MITT groups. Conclusion: Patients with COPD treated with SITT showed improved treatment persistence and adherence, as well as a reduction in the risk of moderate-to-severe exacerbation, severe exacerbation, and mortality compared to patients treated with MITT in the Chinese population. Clinical Trial Registration: https://www.chictr.org.cn/, identifier ChiCTR-POC-17010431.

Lung Function Impairment, Associating Hyperinflation with Impaired Diffusion Capacity and Transfer Coefficient, Is a Risk Factor for Hip Osteoporosis in Patients with Chronic Obstructive Pulmonary Disease

Chronic obstructive pulmonary disease (COPD) is a risk factor for osteoporosis. Our objective is to determine if functional indices associated with emphysema on pulmonary function tests (DLCO—diffusion capacity of the lung for CO-; DLCO/AV—DLCO corrected for alveolar volume- and TLC—total lung capacity), considered alone or together, can identify COPD patients with osteoporosis. Methods: 90 COPD patients underwent dual-energy X-ray absorptiometry (DEXA) and pulmonary function tests. Results: 26% of the COPD patients were osteoporotic. In univariate analysis, each functional parameter associated with emphysema, analyzed separately, was not associated with osteoporosis. In contrast, patients with hyperinflation associated with impaired diffusion capacity and transfer coefficient, defined by the association of the three functional indices (DLCO < 70%, DLCO/AV < 80% and CPT > 115%), had significantly more osteoporosis at the total hip (OR: 5.9, CI: 1.5–23.8, p = 0.013). In multivariate analysis, this phenotype was confirmed as an independent factor associated with hip osteoporosis. In contrast, COPD airway obstruction severity, based on FEV1 (%), was not associated with osteoporosis. A lower BMI, female gender and age were also identified as osteoporosis risk factors. Conclusions: COPD patients with hyperinflation associated with impaired diffusion capacity and transfer coefficient are at higher risk for osteoporosis. Pulmonary function tests associated with emphysema detection can help to identify COPD patients with osteoporosis, in addition to the classical risk factors.

Contemporary Concise Review 2022: Chronic obstructive pulmonary disease

International respiratory organizations now recommend using lower limit of normal and standardized residuals to diagnose airflow obstruction and COPD though using a fixed ratio <0.7 is simpler and robustly predicts important clinical outcomes. The most common COPD comorbidities are coronary artery calcification, emphysema and bronchiectasis. COPD patients with psychological (high anxiety and depression) and cachectic (underweight and osteoporotic) comorbidity have higher mortality and exacerbate more. Serum eosinophil count remains an important COPD biomarker and we have greater clarity about normal eosinophil levels in COPD and the wider population. Criteria for entry into COPD clinical trials continue to exclude many patients, in particular those at greater risk of exacerbation and death. The effect of hyperinflation on cardiac function impacts COPD mortality and is an important target for successful lung volume reduction procedures.

TSLP and HMGB1: Inflammatory Targets and Potential Biomarkers for Precision Medicine in Asthma and COPD

The airway epithelium, through pattern recognition receptors expressed transmembrane or intracellularly, acts as a first line of defense for the lungs against many environmental triggers. It is involved in the release of alarmin cytokines, which are important mediators of inflammation, with receptors widely expressed in structural cells as well as innate and adaptive immune cells. Knowledge of the role of epithelial cells in orchestrating the immune response and mediating the clearance of invading pathogens and dead/damaged cells to facilitate resolution of inflammation is necessary to understand how, in many chronic lung diseases, there is a persistent inflammatory response that becomes the basis of underlying pathogenesis. This review will focus on the role of pulmonary epithelial cells and of airway epithelial cell alarmins, in particular thymic stromal lymphopoietin (TSLP) and high mobility group box 1 (HMGB1), as key mediators in driving the inflammation of chronic lung diseases, such as asthma and chronic obstructive pulmonary disease (COPD), evaluating the similarities and differences. Moreover, emerging concepts regarding the therapeutic role of molecules that act on airway epithelial cell alarmins will be explored for a precision medicine approach in the context of pulmonary diseases, thus allowing the use of these molecules as possible predictive biomarkers of clinical and biological response.

COPD: Providing the right treatment for the right patient at the right time

Chronic Obstructive Pulmonary Disease (COPD) is a common disease associated with significant morbidity and mortality that is both preventable and treatable. However, a major challenge in recognizing, preventing, and treating COPD is understanding its complexity. While COPD has historically been characterized as a disease defined by airflow limitation, we now understand it as a multi-component disease with many clinical phenotypes, systemic manifestations, and associated co-morbidities. Evidence is rapidly emerging in our understanding of the many factors that contribute to the pathogenesis of COPD and the identification of "early" or "pre-COPD" which should provide exciting opportunities for early treatment and disease modification. In addition to breakthroughs in our understanding of the origins of COPD, we are optimizing treatment strategies and delivery of care that are showing impressive benefits in patient-centered outcomes and healthcare utilization. This special issue of Respiratory Medicine, "COPD: Providing the Right Treatment for the Right Patient at the Right Time" is a summary of the proceedings of a conference held in Stresa, Italy in April 2022 that brought together international experts to discuss emerging evidence in COPD and Pulmonary Rehabilitation in honor of a distinguished friend and colleague, Claudio Ferdinando Donor (1948-2021). Claudio was a true pioneer in the field of pulmonary rehabilitation and the comprehensive care of individuals with COPD. He held numerous leadership roles in in the field, provide editorial stewardship of several respiratory journals, authored numerous papers, statement and guidelines in COPD and Pulmonary Rehabilitation, and provided mentorship to many in our field. Claudio's most impressive talent was his ability to organize spectacular conferences and symposia that highlighted cutting edge science and clinical medicine. It is in this spirit that this conference was conceived and planned. These proceedings are divided into 4 sections which highlight crucial areas in the field of COPD: (1) New concepts in COPD pathogenesis; (2) Enhancing outcomes in COPD; (3) Non-pharmacologic management of COPD; and (4) Optimizing delivery of care for COPD. These presentations summarize the newest evidence in the field and capture lively discussion on the exciting future of treating this prevalent and impactful disease. We thank each of the authors for their participation and applaud their efforts toward pushing the envelope in our understanding of COPD and optimizing care for these patients. We believe that this edition is a most fitting tribute to a dear colleague and friend and will prove useful to students, clinicians, and researchers as they continually strive to provide the right treatment for the right patient at the right time. It has been our pleasure and a distinct honor to serve as editors and oversee such wonderful scholarly work.

Surfactant Protein B Plasma Levels: Reliability as a Biomarker in COPD Patients

Background: The diagnosis of COPD is based on both clinical signs and functional tests. Although there are different functional tests used to assess COPD, no reliable biomarkers able to provide information on pathogenesis and severity are available. The aim of the present study is to explore the relationship between surfactant protein B (Sp-B) serum levels and clinical, radiological, and functional pulmonary parameters in COPD patients. Methods: Forty COPD patients and twenty smokers without airflow limitations or respiratory symptoms were enrolled. Each patient was given questionnaires (CAT and mMRC) and 6MWT, spirometry, DLCO, and computer tomography (CT) were performed. All participants underwent a venous blood sample drawing, and quantitative detection of their Sp-B plasma levels was performed by an enzyme-linked immunosorbent assay. The spirometry and Sp-B plasma levels were assessed after 12 months. Results: A statistically significant difference was found in the plasma Sp-B levels between COPD patients compared to the other group (4.72 + 3.2 ng/mL vs. 1.78 + 1.5 ng/mL; p < 0.001). The change in FEV1 after 12 months (Delta FEV1) showed a significantly negative correlation with respect to the change in Sp-B levels (Delta SpB) (r = −0.4; p < 0.05). This correlation indicates that increasing the plasma dosage of SpB is a foretoken of functional decline. Conclusions: SpB may be considered as a useful marker in COPD assessment and provides prognostic information on lung functional decline. Despite its usefulness, further studies are needed to define its reliability as a biomarker.

Disease burden of COPD in the Chinese population: a systematic review

BACKGROUND

Chronic obstructive pulmonary disease (COPD) is one of the main contributors to the global burden of disease.

OBJECTIVES

This systematic review aimed to evaluate the disease burden of COPD in the Chinese population and to determine the factors influencing the economic burden of the disease.

DESIGN

This is a systematic review study.

DATA SOURCES AND METHODS

We searched PubMed, Web of Science, Embase, Chinese National Knowledge Infrastructure, WANGFANG Data, and VIP databases for studies regarding the disease burden of COPD in mainland China published before 31 December 2022. The Agency for Healthcare Research and Quality's recommendation rating tool assessed the cross-sectional studies' risk of bias.

RESULTS

A total of 45 studies were included. The disability-adjusted life years (DALYs) for COPD have generally decreased in the Chinese population over the past 30 years. The total number of DALYs due to COPD in China decreased from 26.12 million person-years to 19.92 million person-years, with an annual decline rate of 0.9%. Subjects aged 40 years and older make up the majority of those with COPD in the Chinese population, and the condition is more prevalent among males than females, in rural areas than urban places, and in the West than the East. The median direct medical cost of COPD ranges from 150 to 2014 USD per capita per year. Among 23 influencing factors, age, hospitalization days, hospital type, gender, and career were the most significant variables that had an impact on the economic burden of COPD patients.

CONCLUSION

The overall burden of COPD in China has been decreasing over the past 30 years. But there is a lack of standardized indicators for the economic burden of COPD patients in China, and it is recommended to establish a unified standard.

REGISTRATION

The systematic review protocol was prospectively registered with PROSPERO (No. CRD42023393429).

iNOS Deletion in Alveolar Epithelium Cannot Reverse the Elastase-Induced Emphysema in Mice

BACKGROUND

Chronic obstructive pulmonary disease (COPD) is the third leading cause of death worldwide. In addition to chronic bronchitis and emphysema, patients often develop at least mild pulmonary hypertension (PH). We previously demonstrated that inhibition of inducible nitric oxide synthase (iNOS) prevents and reverses emphysema and PH in mice. Interestingly, strong iNOS upregulation was found in alveolar epithelial type II cells (AECII) in emphysematous murine lungs, and peroxynitrite, which can be formed from iNOS-derived NO, was shown to induce AECII apoptosis in vitro. However, the specific cell type(s) that drive(s) iNOS-dependent lung regeneration in emphysema/PH has (have) not been identified yet.

AIM

we tested whether iNOS knockout in AECII affects established elastase-induced emphysema in mice.

METHODS

four weeks after a single intratracheal instillation of porcine pancreatic elastase for the induction of emphysema and PH, we induced iNOS knockout in AECII in mice, and gave an additional twelve weeks for the potential recovery.

RESULTS

iNOS knockout in AECII did not reduce elastase-induced functional and structural lung changes such as increased lung compliance, decreased mean linear intercept and increased airspace, decreased right ventricular function, increased right ventricular systolic pressure and increased pulmonary vascular muscularization. In vitro, iNOS inhibition did not reduce apoptosis of AECII following exposure to a noxious stimulus.

CONCLUSION

taken together, our data demonstrate that iNOS deletion in AECII is not sufficient for the regeneration of emphysematous murine lungs, and suggest that iNOS expression in pulmonary vascular or stromal cells might be critically important in this regard.