Spanish COPD Guidelines (GesEPOC 2021): Non-pharmacological Treatment Update

Characterization of Inactive COPD Patients: Barriers to Physical Activity and Perceived Impact of Inactivity

BACKCROUND

Chronic obstructive pulmonary disease (COPD) is characterized by high morbidity and mortality, with physical inactivity being a major contributor to poor outcomes. This study aims to identify subgroups of inactive COPD patients by analyzing reported barriers to physical activity and the perceived impact of inactivity on their disease.

METHODS

In 91 consecutive stable COPD patients, physical activity was measured using a SenseWear armband and the SAQ-COPD questionnaire, to define inactivity as a physical activity level <1.69. Clinical and functional assessment included measurement of lung volumes, diffusing capacity, muscle strength, six-minute walk test and progressive cardiorespiratory exercise test. Cluster analysis was performed based on patients' responses to the profile and impact sections of SAQ-COPD questionnaire.

RESULTS

In 70 inactive COPD patients, three distinct clusters were identified: Cluster 1 showed significant functional limitations, particularly dyspnea and leg fatigue, alongside worse exercise tolerance and dynamic hyperinflation. Cluster 2 displayed few functional limitations but reported a lack of interest in physical activity as the primary reason for inactivity, with poorer sleep quality observed. Cluster 3 exhibited a high perceived impact of inactivity despite reporting fewer physical limitations, with psychological factors such as fear and discouragement acting as primary barriers. Factor analysis revealed two principal components: perceived impact of inactivity and limiting factors for exercise.

CONCLUSION

These findings highlight the heterogeneity among inactive COPD patients and emphasize the need for tailored interventions targeting both physical and psychological barriers. SAQ-COPD questionnaire may be a useful instrument for this individualized assessment of inactive COPD patients.

Association of dietary patterns with chronic respiratory health among U.S. adults

Background

Respiratory health is closely related to immune system function, and diet can also influence immune homeostasis. Diet, an important part of a healthy lifestyle, is also linked to respiratory health. We aimed to explore the relationship between different dietary patterns and the risk of chronic respiratory diseases (CRDs), including chronic bronchitis (CB), emphysema, and asthma.

Method

A total of 23,042 adults from the United States were selected from the National Health and Nutrition Examination Survey (NHANES) dataset between 2007 and 2018. Diet quality was assessed using 2-day, 24-hour dietary recall data and quantified as the Healthy Eating Index-2020 (HEI-2020), the Dietary Inflammation Index (DII), the Mediterranean Dietary Index (MEDI), and the Dietary Approaches to Stop Hypertension Index (DASHI). Binary logistic regression models, restricted cubic splines (RCS), and the weighted quartile sum (WQS) models were used to assess the relationship between diet quality and the risk of CB, emphysema, and asthma.

Results

In logistic regression analyses of the four dietary indices with the three chronic respiratory diseases, it was consistently observed that higher dietary quality scores were linked to a reduced risk of respiratory disease. These consistent trends were also evident in the assessments of the dose-response relationship between dietary quality score and the risk of respiratory disease. Furthermore, evaluations of the combined effects of dietary components across different dietary indices in the risk of chronic respiratory disease yielded results consistent with the logistic regression models. Notably, high-quality protein, minerals, and fiber-rich fruits and vegetables emerged as the food groups making the most significant contributions to health across different dietary indices.

Conclusion

Low-quality diets, lacking in high-quality protein, minerals, and fruits and vegetables rich in dietary fiber, are associated with a higher risk of chronic respiratory disease, regardless of the dietary index used to measure diet quality.

Exosome microRNA-125a-5p derived from epithelium promotes M1 macrophage polarization by targeting IL1RN in chronic obstructive pulmonary disease

BACKGROUND

The interplay between airway epithelium and macrophages plays a pivotal role in Chronic Obstructive Pulmonary Disease (COPD) pathogenesis. Exosomes, which transport miRNA cargo, have emerged as novel mediators of intercellular communication. MicroRNA-125a-5p (miR-125a-5p) has been implicated in macrophage polarization.This study aims to investigate the role of exosomal miR-125a-5p in the dysfunctional epithelium-macrophage cross-talk in cigarette smoke (CS)-induced COPD.

METHODS

In cell models, THP-1 monocytic cells were differentiated into macrophages (M0). Human bronchial epithelial cells treated with CS extract (CSE) were co-cultured with M0. Exosomes were isolated from culture media using commercial kits and characterized using nanoparticle tracking analysis (NTA) and transmission electron microscopy (TEM). Exosomes labeled with PKH26 red fluorescent cell linker kits were incubated with macrophages. Luciferase reporter assay was used to confirm the target gene of miR-125a-5p. In mouse experiments, inhibiting miR-125a-5p was utilized to examine its role in macrophage polarization. Furthermore, the underlying mechanism was explored.

RESULTS

In vitro results indicated that CSE treatment led to upregulation of miR-125a-5p in HBE cells, and exosomes contained miR-125a-5p. PKH26-labeled exosomes were internalized by macrophages. Co-culture experiments between bronchial epithelial cells and miR-125a-5p mimic resulted in significant increase in M1 macrophage markers (TNF-α, iNOS-2, IL-1β) and decrease in M2 markers (IL-10 and Arg-1). In COPD mouse models, miR-125a-5p inhibitor reduced levels of TNF-α, IL-1β, and IL-6. Luciferase assays revealed that miR-125a-5p inhibitors enhanced the relative luciferase activity of IL1RN. Mechanistic experiments demonstrated that HBE-derived exosomes transfected with miR-125a-5p mimics promoted upregulation of MyD88, TRAF6, p65, iNOS-2, and downregulation of Arg-1.

CONCLUSION

This study suggests that exosomal miR-125a-5p may act as a mediator in the cross-talk between airway epithelium and macrophage polarization in COPD. Exosomal miR-125a-5p targeting IL1RN may promote M1 macrophage polarization via the MyD88/NF-κB pathway.

Association of the Healthy Dietary Index 2020 and its components with chronic respiratory disease among U.S. adults

Background

Chronic respiratory disease is an important public health problem in the United States and globally. Diet, an important part of a healthy lifestyle, is also relevant to chronic respiratory health. We aimed to explore the relationship between overall dietary quality and the risk of chronic respiratory disease (CRD), include chronic bronchitis (CB), emphysema and asthma.

Method

A total of 4,499 United States adults were extracted from the National Health and Nutrition Examination Survey (NHANES) in 2017-2018. Diet quality was assessed using 2 day, 24 h dietary recall data and quantified as the Healthy Diet Index (HEI)-2020 score. Binary logistic regression models, restricted cubic splines (RCS) and generalized additive modeling (GAM), the weighted quartile sum (WQS) and qgcom models were used to assess the relationship between HEI-2020 scores and risk of CB, emphysema and asthma.

Results

High HEI-2020 scores are associated with low risk of chronic respiratory disease (CB: 0.98, 0.97-0.99; emphysema: 0.98, 0.97-0.99; asthma: 0.98, 0.97-0.99) and consistent results across different dietary variable categorization (Tertile: CB: 0.58, 0.42-0.81; asthma: 0.51, 0.35-0.74; Quartile: CB: 0.57, 0.34-0.97; asthma: 0.56, 0.36-0.86) and different weighting models. Negative dose-response relationship between dietary quality and risk of chronic respiratory disease also shown in RCS and GAM models. The WQS and qgcom models also showed a healthy mixing effect of dietary components on respiratory disease, with high-quality proteins, vegetables, and fruits making the heaviest contributions.

Conclusion

Higher HEI-2020 scores were associated with lower risk of CB, emphysema, and asthma. Following Dietary Guidelines for Americans 2020-2025 could support enhanced respiratory health.

Motivation and Confidence about Physical Activity in Chronic Obstructive Pulmonary Disease Patients: Health Benefits Matter to Patients

INTRODUCTION

Physical activity (PA) has shown great benefits in patients with chronic obstructive pulmonary disease (COPD); however, their PA is below average. Motivational factors associated with PA in COPD have not been widely studied and could be a target for improving adherence to PA. The objective of our study was to identify and understand the different motivational and confidence factors related to low levels of PA in a COPD cohort.

METHOD

Observational, prospective, multicenter study of COPD patients. Sociodemographic data, respiratory symptoms, comorbidities, spirometry, and exercise capacity were collected. PA was measured using the Dynaport accelerometer and patient motivation and confidence in PA were assessed by a questionnaire previously used in a COPD population in the USA.

RESULTS

Eighty six COPD patients were included, 68.6% being male, with a mean (SD) age of 66.6 (8.5) years and a mean forced expiratory volume in the first second (%) of 50.9% (17.3%). The mean walking time was 82.8 (37.8) minutes/day. Questions related to health benefits and enjoying exercise were ranked highest in the motivation questionnaire and statistically significant differences were found in PA measures between patients with low and high motivation. A lack of confidence regarding hot weather and health-related issues significantly influenced PA levels. Advice from third parties, including healthcare providers, was not associated with higher PA levels.

CONCLUSIONS

Improving the health of COPD patients is their main motivation to perform PA. Lack of confidence when it is hot or when they fear for their health is related to low levels of PA. Advice from third parties, including healthcare professionals, is not associated with higher PA. These results are relevant for developing strategies to increase the adherence of COPD patients to PA programs.

The Natural History of Severe Chronic Obstructive Pulmonary Disease: The SPOCCAT Study Protocol

Introduction

Patients with severe chronic obstructive pulmonary disease (COPD) are often underrepresented in cohorts, creating uncertainty about the natural history and prognostic factors of this subgroup. Our goal was to describe the SPOCCAT (Severe COPD: Prospective Observational study of COPD in Catalonia) study protocol.

Material and methods

SPOCCAT is a non-interventional, multicenter, prospective cohort study of patients with severe COPD (FEV1% predicted < 50%). The study aims to: (1) establish a five-year prospective cohort; (2) identify demographic and clinical characteristics; (3) describe treatment patterns; (4) better understand the natural history of severe COPD, including lung function decline, exacerbation rates, and mortality; and (5) identify prognostic factors for poor outcomes.Recruitment began in January 2024, and the cohort will be followed for a minimum of five years (or until death or lung transplant) with follow-up visits every 12 months. Baseline data include demographics, laboratory analyses, comorbidities, lung function, respiratory symptoms, respiratory disease exacerbations and etiology, quality of life, physical activity, chest computed tomography, and treatment. Annual follow-up visits will assess changes in treatment, exacerbation frequency and severity, microbiological outcomes, complementary tests, and mortality. Participation requires written informed consent from all patients, with data collected in an anonymized electronic Case Report Form.

Results

The results of the SPOCCAT study will provide relevant information about the characteristics, treatment, and prognostic factors of severe COPD.

Conclusions

SPOCCAT has the potential to enhance understanding of severe COPD, exploring innovative aspects and establishing a robust research framework for future COPD-related projects.

Supplemental oxygen and noninvasive ventilation

The respiratory system attempts to maintain normal levels of oxygen and carbon dioxide. However, airflow limitation, parenchymal abnormalities and dysfunction of the respiratory pump may be compromised in individuals with advanced COPD, eventually leading to respiratory failure, with reduced arterial oxygen tension (hypoxaemia) and/or increased arterial carbon dioxide tension (P aCO2 ; hypercapnia). Hypoxaemia may persist in individuals with severe COPD despite smoking cessation and optimisation of pharmacotherapy. Long-term oxygen therapy (LTOT) can improve survival in those with severe daytime hypoxaemia, whereas those with less severe hypoxaemia may only have improved exercise capacity and dyspnoea. Changes in respiratory physiology that occur during sleep further predispose to hypoxaemia, particularly in individuals with COPD. However, the major cause of hypoxaemia is hypoventilation. Noninvasive ventilation (NIV) may reduce mortality and need for intubation in individuals with COPD and acute hypercapnic respiratory failure. However, NIV may also improve survival and quality of life in individuals with stable, chronic hypercapnia and is now suggested for those with prolonged hypercapnia (e.g. P aCO2 >55 mmHg 2-6 weeks after hospital discharge) when clinically stable and after optimisation of medical therapy including LTOT if indicated. Many questions remain about the optimal mode, settings and goal of NIV therapy.