Biomarkers for differentiation of patients with asthma and chronic obstructive pulmonary disease

Analysis of the relationship between comorbid obstructive sleep apnea and clinical outcomes in patients with asthma in Japan

BACKGROUND

Asthma and obstructive sleep apnea (OSA) are prevalent chronic respiratory disorders, which often coexist and interact with each other. Obesity is an important risk factor shared by them. The rate of obesity is lower in Japan versus Western countries. Hence, the co-existence of asthma and OSA has not been investigated in Japan.

METHODS

Ninety-seven outpatients with asthma were recruited. Patients wore a portable monitor for sleep study. Background data, pulmonary function, blood tests, and patient-reported outcomes including gastroesophageal reflux disease, sleepiness, sleep quality, asthma control, cough and respiratory symptoms, and health status, were assessed.

RESULTS

Of the patients, 19 (19.6 %), 40 (41.2 %), 24 (24.7 %), and 14 (14.4 %) were classified into non-, mild, moderate, and severe OSA groups. Non-OSA patients were younger than those in other groups (p < 0.05). The BMI of patients with moderate and severe OSA, was higher than that of non-OSA patients (p < 0.05). Pulmonary function, FeNO, serum IgE, and the number of peripheral eosinophils were not significantly different between groups. Nonetheless, compared with the other groups, treatment step was the highest, and the Asthma Control Test, Leicester Cough Questionnaire, COPD Assessment Test, and Asthma Health Questionnaire-33 yielded worst scores in the severe OSA group, and predicted the severe OSA after adjustment by BMI.

CONCLUSIONS

Moderate and severe OSA are highly prevalent among patients with asthma in Japan. Pulmonary function did not differ between groups. However, patients with asthma and severe OSA were linked to more asthma treatment, worse asthma control, more symptoms and cough, and worse health status.

Insights into implementation planning for point-of-care testing to guide treatment of chronic obstructive pulmonary disease exacerbation: a mixed methods feasibility study

The purpose of this mixed methods feasibility study was to gain insights into unmet clinical needs, stakeholder preferences and potential barriers and enablers to adoption for planning the implementation of point-of-care testing for earlier detection and guided treatment of chronic obstructive pulmonary disease (COPD) acute exacerbation in the NHS in England. Exacerbations of COPD cause considerable mortality and morbidity. Earlier identification of exacerbations and guided treatment would lead to reduced exacerbation duration, reduced hospitalizations and mortality, improve health-related quality of life, reduce unnecessary treatments (including inappropriate antibiotic prescribing) which could save the NHS over £400 per patient. During the early stages of product design, we took a multi-disciplinary approach to evidence generation, gaining insights from key stakeholders to test the product concept and inform evidence-based implementation planning. Primary data was collected from 11 health care and service professionals involved in the management of acute COPD exacerbations. Overall, participants agreed that by earlier differentiation of acute exacerbation from stable COPD, patients could be started on appropriate treatment. To implement point-of-care testing into clinical practice, evidence is required to demonstrate the accuracy of differentiating between exacerbation etiologies and to provide information on the beneficial impact to the system in terms of optimized management, reduced long-term side effects, admission avoidance, and cost-effectiveness. This research provides an evidence base for future implementation planning of point-of-care testing for earlier detection and guided treatment of COPD acute exacerbation. Moreover, the technology developers can decide whether to refine the product design and value proposition thereby de-risking product development.

Efficacy of mometasone/indacaterol/glycopyrronium in patients with inadequately controlled asthma with respect to baseline eosinophil count: Post hoc analysis of IRIDIUM study

BACKGROUND

Baseline characteristics could potentially guide asthma treatments. We evaluated whether baseline eosinophil levels affect the efficacy of mometasone/indacaterol/glycopyrronium (MF/IND/GLY) in patients with inadequately controlled asthma.

METHOD

In this post hoc analysis of IRIDIUM study, efficacy of high-dose MF/IND/GLY (160/150/50 μg, once-daily [o.d.]) versus high-dose MF/IND (320/150 μg o.d.) and high-dose fluticasone/salmeterol (FLU/SAL [500/50 μg, twice-daily [b.i.d.]); and efficacy of pooled MF/IND/GLY (160/150/50 μg and 80/150/50 μg) versus pooled MF/IND (320/150 μg and 160/150 μg) was evaluated in patient subgroups with baseline blood eosinophil count of <300 cells/μL or ≥300 cells/μL.

RESULTS

Overall, 3065 patients were included. At Week 26, high-dose MF/IND/GLY showed improved trough FEV1 versus high-dose MF/IND (Δ78mL [<300 cells/μL]; Δ54mL [≥300 cells/μL]) and FLU/SAL (Δ112mL [<300 cells/μL]; Δ98mL [≥300 cells/μL]). Similarly, pooled MF/IND/GLY also showed improved trough FEV1 versus pooled MF/IND (Δ75mL [<300 cells/μL]; Δ68mL [≥300 cells/μL]). Over 52 weeks, high-dose MF/IND/GLY reduced the annualized rate of moderate or severe asthma exacerbations by 23% and 10%, severe exacerbations by 31% and 15%, and all exacerbation by 33% and 10% versus high-dose MF/IND for subgroups with <300 cells/μL and ≥300 cells/μL, respectively; and by 33% and 41%, 45% and 42%, 42% and 39% versus FLU/SAL, respectively. Similarly, pooled MF/IND/GLY reduced exacerbations by 22% and 8%, 21% and 7%, 27% and 8%, versus pooled MF/IND, for the respective subgroups.

CONCLUSION

MF/IND/GLY showed improvement in lung function and reduction in asthma exacerbations over MF/IND and FLU/SAL independent of baseline eosinophil levels, indicating that eosinophil levels did not affect the efficacy of MF/IND/GLY in patients with inadequately controlled asthma.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT02571777 (IRIDIUM).

Association between Serum Levels of Interleukin-25/Thymic Stromal Lymphopoietin and the Risk of Exacerbation of Chronic Obstructive Pulmonary Disease

Th2 inflammation is associated with various characteristics of patients with chronic obstructive pulmonary disease (COPD). In this study, we analyzed the COPD exacerbation risk associated with serum levels of interleukin (IL)-25/thymic stromal lymphopoietin (TSLP) and eosinophils. We studied the KOCOSS cohort, a multicenter COPD cohort created by 54 medical centers in South Korea. We extracted data collected between April 2012 and August 2020. We measured serum levels of TSLP and IL-25 in those who agreed to provide blood, and assessed exacerbation risk according to each. In all, 562 patients were enrolled. The IL-25-high group had a lower St. George's Respiratory Questionnaire score than others, and the TSLP-high group had a poorer exercise capacity than the TSLP-low group. There were no significant differences in the forced expiratory volume in 1 s (FEV1), the levels of Th2 inflammatory biomarkers, or the exacerbation histories between the two groups. The 3-year decline in FEV1 was not significantly affected by IL-25 or TSLP levels. In terms of 1-year exacerbation risk, individuals in the IL-25-high group were at lower risk for moderate-to-severe exacerbation than others. A high TSLP level was associated with a lower risk of severe exacerbation but only in the eosinophil-low group. Serum levels of IL-25 are negatively correlated with moderate-to-severe exacerbation risk in this cohort. A negative correlation between severe exacerbation risk and TSLP level was apparent only in the eosinophil-low group.

Angiogenesis, Lymphangiogenesis, and Inflammation in Chronic Obstructive Pulmonary Disease (COPD): Few Certainties and Many Outstanding Questions

Chronic obstructive pulmonary disease (COPD) is characterized by chronic inflammation, predominantly affecting the lung parenchyma and peripheral airways, that results in progressive and irreversible airflow obstruction. COPD development is promoted by persistent pulmonary inflammation in response to several stimuli (e.g., cigarette smoke, bacterial and viral infections, air pollution, etc.). Angiogenesis, the formation of new blood vessels, and lymphangiogenesis, the formation of new lymphatic vessels, are features of airway inflammation in COPD. There is compelling evidence that effector cells of inflammation (lung-resident macrophages and mast cells and infiltrating neutrophils, eosinophils, basophils, lymphocytes, etc.) are major sources of a vast array of angiogenic (e.g., vascular endothelial growth factor-A (VEGF-A), angiopoietins) and/or lymphangiogenic factors (VEGF-C, -D). Further, structural cells, including bronchial and alveolar epithelial cells, endothelial cells, fibroblasts/myofibroblasts, and airway smooth muscle cells, can contribute to inflammation and angiogenesis in COPD. Although there is evidence that alterations of angiogenesis and, to a lesser extent, lymphangiogenesis, are associated with COPD, there are still many unanswered questions.

Modern understanding of bronchial asthma with fixed airflow obstruction

The review provides data on one of the phenotypes of severe bronchial asthma it is asthma with fixed airway obstruction. According to data published today, there is no single pathway for the formation of fixed airway obstruction in patients with severe asthma. Increasing knowledge of the pathophysiology of fixed airway obstruction, as well as identifying the most significant risk factors, is essential for the successful treatment of such patients. In addition, the development of fixed obstruction is associated with a worse and sometimes fatal prognosis. Expanding the existing views is also necessary to overcome the difficulties of differential diagnosis between bronchial asthma with fixed airway obstruction and bronchial asthma in combination with COPD. All this will optimize the approach to the management of patients with bronchial asthma to prevent the formation of fixed airway obstruction.

Asthma-COPD overlap: current understanding and the utility of experimental models

Pathological features of both asthma and COPD coexist in some patients and this is termed asthma-COPD overlap (ACO). ACO is heterogeneous and patients exhibit various combinations of asthma and COPD features, making it difficult to characterise the underlying pathogenic mechanisms. There are no controlled studies that define effective therapies for ACO, which arises from the lack of international consensus on the definition and diagnostic criteria for ACO, as well as scant in vitro and in vivo data. There remain unmet needs for experimental models of ACO that accurately recapitulate the hallmark features of ACO in patients. The development and interrogation of such models will identify underlying disease-causing mechanisms, as well as enabling the identification of novel therapeutic targets and providing a platform for assessing new ACO therapies. Here, we review the current understanding of the clinical features of ACO and highlight the approaches that are best suited for developing representative experimental models of ACO.

Understanding the pathogenesis of asthma-COPD overlap is critical for improving therapeutic approaches. We present current knowledge on asthma-COPD overlap and the requirements for developing an optimal animal model of disease.https://bit.ly/3lsjyvm

Periostin and Thymic Stromal Lymphopoietin-Potential Crosstalk in Obstructive Airway Diseases

Periostin and thymic stromal lymphopoietin (TSLP) are newly described markers of obstructive airway diseases and the mechanism by which both markers participate in immune response remains poorly understood. The aim of our study was to determine periostin and TSLP concentration in serum and induced sputum (IS) in patients with atopic asthma, chronic obstructive pulmonary disease (COPD), and controls, as well as to evaluate the potential link between periostin, TSLP, and Th2 immune response. Serum and IS levels of periostin, TSLP, IL-4, and IL-13 were determined in 12 atopic asthmatics, 16 COPD sufferers, and 10 controls. We noticed a significantly higher IS periostin and TSLP concentration at protein and mRNA level in asthmatics compared to the two other groups; additionally, periostin and TSLP were correlated positively with IS eosinophil count. A strong positive correlation between IS periostin and TSLP protein levels (r = 0.96) as well as mRNA expression level (r = 0.95) was found in patients with asthma. The results of our study show that periostin and TSLP are associated with eosinophilic airway inflammation and seem to be important drivers of atopic asthma but not COPD pathobiology. Very strong correlations between local periostin, TSLP, eosinophils, and IL-4 in asthma point to the link between periostin-TSLP and Th2 response.

Prospective development of practical screening strategies for diagnosis of asthma-COPD overlap

BACKGROUND AND OBJECTIVE

ACO is a syndrome with high prevalence. However, a pragmatic diagnostic criterion to differentiate ACO is non-existent. We aimed to establish an effective model for screening ACO.

METHODS

A multicentre survey was developed to assess the clinical criteria considered important and applicable by pulmonologists for screening ACO. These experts were asked to take the surveys twice. The expert grading method, analytic hierarchy process and ROC curve were used to establish the model, which was then validated by a cross-sectional study of 1066 patients. The GINA/GOLD document was the gold standard in assessing this model.

RESULTS

Increased variability of symptoms, paroxysmal wheezing, dyspnoea, historical diagnosis of COPD or asthma, allergic constitution, exposure to risk factors, the FEV1 /FVC < 70% and a positive BDT were important for screening ACO. According to the weight of each criterion, we confirmed that patients meeting six or more of these eight criteria should be considered to have ACO. We called this Chinese screening model for ACO 'CSMA'. It differentiated patients with ACO with a sensitivity of 83.33%, while the sensitivity of clinician-driven diagnosis had a sensitivity of only 42.73%.

CONCLUSION

CSMA is a workable model for screening ACO and provides a simple tool for clinicians to efficiently diagnose ACO.

Blood biomarkers in chronic airways diseases and their role in diagnosis and management

INTRODUCTION

The complexity and heterogeneous nature of asthma and chronic obstructive pulmonary disease (COPD) results in difficulties in diagnosing and treating patients. Biomarkers that can identify underlying mechanisms, identify patient phenotypes and to predict treatment response could be of great value for adequate treatment. Areas covered: Biomarkers play an important role for the development of novel targeted therapies in airways disease. Blood biomarkers are relatively non-invasive, easy to obtain and easy to apply in routine care. Several blood biomarkers are being used to diagnose and monitor chronic airways diseases, as well as to predict response to treatment and long-term prognosis. Blood eosinophils are the best studied biomarker, the most applied in clinical practice, and until now the most promising of all blood biomarkers. Other blood biomarkers, including serum periostin, IgE and ECP and plasma fibrinogen are less studied and less relevant in clinical practice. Recent developments include the use of antibody assays of many different cytokines at the same time, and 'omics' techniques and systems medicine. Expert commentary: With the exception of blood eosinophils, the use of blood biomarkers in asthma and COPD has been rather disappointing. Future research using new technologies like big-data analysis of blood samples from real-life patient cohorts will probably gain better insight into underlying mechanisms of different disease phenotypes. Identification of specific molecular pathways and associated biomarkers will then allow the development of new targets for precision medicine.