Differences in the Quantitative HRCT Characteristics of Patients with Asthma, COPD and Asthma-COPD Overlap and Their Relationships with Pulmonary Function.

Purpose: We compared pulmonary function indices and quantitative CT parameters of airway remodeling, air trapping, and emphysema in asthmatic patients and patients with COPD and asthma-COPD overlap (ACO) and explored their relationships with airflow limitation. Patients and Methods: Patients with asthma (n=48), COPD (n=52), and ACO (n=30) and controls (n=54) who completed pulmonary function tests and HRCT scans were retrospectively enrolled in our study. Quantitative CT analysis software was used to assess emphysema (LAA%), airway wall dimensions (wall area (WA), luminal area (LA), and wall area percentage (WA%)), and air trapping ((relative volume change of -860 HU to -950 HU (RVC-860 to-950) and the expiration-to-inspiration ratio of the mean lung density (MLDE/I))). Differences in pulmonary function and HRCT parameters were compared among the groups. Spearman correlation analysis and regression analysis were utilized to explore structure‒function relationships. Results: The LAA% in COPD and ACO patients was significantly greater than that in asthmatic patients and controls. The WA% and WA in COPD and ACO patients were greater than those in controls, whereas the WA% and LA between asthmatic patients and controls reached statistical significance. The RVC-860 to -950 levels decreased in the following order: ACO, COPD, and asthma. RVC-860 to -950 independently predicted FEV1% in asthmatic patients; LAA% and MLDE/I in COPD patients; and LAA%, WA% and RVC-860 to -950 in ACO patients. Conclusion: Comparable emphysema was observed in patients with COPD and ACO but not in asthmatic patients. All patients exhibited proximal airway remodeling. The bronchi were thickened outward in COPD and ACO patients but are thickened inward in asthmatic patients. Furthermore, air trapping in ACO patients was the most severe among all the groups. Indirect lung densitometry measurements might be more predictive of the degree of airflow limitation than direct airway measurements in obstructive airway diseases.

Phenotyping chronic respiratory diseases with airways obstruction.

Given the high prevalence of asthma-chronic obstructive pulmonary disease overlap (ACO) in Vietnam, there is an urgent need to establish a simplified strategy for categorising patients as either having asthma or chronic obstructive pulmonary disease (COPD). This classification would streamline the application of treatment recommendations outlined by the Global Initiative for Asthma (GINA) and the Global Initiative for Chronic Obstructive Lung Disease (GOLD).Patients with obstructive lung function were classified as having COPD, asthma, or ACO based on GINA/GOLD guidelines. We hypothesised that ACO-like asthma (ACO-A) would present with positive skin prick tests (SPTs) or early onset of symptoms without a history of tuberculosis (TB), while those with ACO-like COPD (ACO-B) would exhibit negative SPTs and late onset of symptoms and/or a history of TB.Among 235 patients, the prevalence of asthma, ACO-A, ACO-B, and COPD was respectively 21%, 22%, 17%, and 40%. Allergic history, rhinitis, and childhood asthma were associated with ACO-A, while high cumulative smoking was correlated with ACO-B. Socio-economic and demographic parameters, medical history, clinical features, smoking habits, lung function, and para-clinical investigations significantly differed between "all asthma" (i.e., individuals with asthma combined with ACO-A) and "all COPD" (i.e., individuals with COPD combined with ACO-B).Based on SPTs, history of TB, and onset age, ACO patients may be defined as people with asthma or COPD..

Epidemiological characteristics of asthma-COPD overlap, its association with all-cause mortality, and the mediating role of depressive symptoms: evidence from NHANES 2005-2018.

BACKGROUND: Asthma-COPD overlap (ACO) is a distinct and intricate respiratory condition that requires specific attention and management. The objective of this cohort study was to examine the epidemiological characteristics of ACO, explore the association between ACO and all-cause mortality, and investigate the potential mediating role of depressive symptoms in this association. METHODS: This retrospective cohort study used data from the National Health and Nutrition Examination Survey (NHANES) 2005-2018 and National Death Index (NDI) 2019. A total of 22,745 participants were included: 705 with ACO, 2352 with asthma-only, 853 with COPD-only, and 18,835 without asthma or COPD. The non-ACO group (N = 22,040) referred to the individuals without ACO. Statistical tests were employed to assess differences in some characteristics between the ACO group and the other groups. Cox proportional hazards models were applied to evaluate the relationship between ACO and all-cause mortality, estimating hazard ratios (HR) with 95% confidence intervals. Mediation analysis was conducted to investigate the potential mediating effects of depressive symptoms on the association of ACO with all-cause mortality. RESULTS: The prevalence of ACO was 3.10% in our study population. Compared to the non-ACO participants, the ACO participants exhibited significantly different characteristics, including higher age, a lower family income-to-poverty ratio, a higher body mass index, higher rates of comorbidities i.e., hypertension, diabetes, hyperlipidemia, cardiovascular disease, and cancer, poorer dietary habits, and a higher rate of depressive disorders. Compared to the participants without ACO, the participants with ACO exhibited a significant increase in all-cause mortality (HR = 1.908, 95%CI 1.578-1.307, p < 0.001). The proportions mediated by depressive symptoms for ACO -associated all-cause mortality were 8.13% (CI: 4.22%-14.00%, p < 0.001). CONCLUSIONS: This study revealed a strong relationship between ACO and all-cause mortality and uncovered a potential psychological mechanism underlying this relationship. Our study indicates the possible necessity of offering comprehensive care to ACO patients, encompassing early detection, lifestyle guidance, and mental health support. Nevertheless, due to the limitations in the study design and the dataset, the results should be interpreted with caution.

Asthma-chronic obstructive pulmonary disease overlap: Results from a national-multicenter study.

Introduction: Patients with asthma-chronic obstructive pulmonary disease (COPD) overlap (ACO) have a greater disease burden than those with COPD or asthma alone. In this study, it was aimed to determine the prevalence, risk factors, and clinical features of ACO because there are limited national data in Türkiye. Materials and Methods: The study was conducted in a cross-sectional design in nine tertiary-care hospitals. The patients followed with a diagnosis of asthma or COPD for at least one year were enrolled in the study. The frequency of ACO and the characteristics of the patients were evaluated in the asthma and COPD groups. Result: The study included 408 subjects (F/M= 205/203, mean age= 56.24 ± 11.85 years). The overall prevalence of ACO in both groups was 20.8% (n= 85). The frequency was higher in the COPD group than in the asthma group (n= 55; 33.3% vs. n= 22; 9.8%), respectively (p= 0.001). Patients with ACO had similarities to patients with COPD in terms of advanced age, sex, smoking, exposure to biomass during childhood, being born in rural areas, and radiologic features. Characteristics such as a history of childhood asthma and allergic rhinitis, presence of chronic sinusitis, NSAID hypersensitivity, atopy, and high eosinophil counts were similar to those of patients with asthma (p<0.001). The annual decline in FEV1 was more prominent in the ACO group (mean= -250 mL) than in the asthma (mean change= -60 mL) and COPD (mean change= -230 mL) groups (p= 0.003). Conclusions: This study showed that ACO was common among patients with asthma and COPD in tertiary care clinics in our country. ACO should be considered in patients with asthma and COPD who exhibit the abovementioned symptoms.

Effect of budesonide formoterol combined with tiotropium bromide on pulmonary function and inflammatory factors in patients with asthma-COPD overlap syndrome.

OBJECTIVE: To investigate the clinical efficacy of combining budesonide formoterol with tiotropium bromide for treating asthma-chronic obstructive pulmonary disease overlap syndrome (AOCS). METHODS: The data of 104 patients with AOCS admitted to our hospital from December 2019 to December 2020 were assessed, randomly and divided into an experimental group (comprising 52 patients, receiving drug combination therapy) and a conventional group (comprising 52 patients, receiving drug therapy alone). Patients' clinical efficacy, pulmonary function, fractioned exhaled nitric oxide (FeNO), immune function, endothelial function, serum lipid peroxidation injury indexes, adverse reactions, and quality of life scores were compared. RESULTS: Prior to treatment, no significant differences were observed in various pulmonary function indicators, FeNO, immune function, endothelial function, and lipid peroxidation injury indexes between the two groups (P > 0.05). However, after treatment, all observation indexes in both groups improved to different levels, with the experimental group -demonstrating -significantly superior improvement, compared to the conventional group (P < 0.05). We also observed that adverse reactions in the experimental group were significantly lower than in the conventional group (P < 0.05). CONCLUSION: The combination of budesonide formoterol to tiotropium bromide in treating asthma-COPD overlap syndrome may significantly improve pulmonary function, endothelial function, and immune status of patients and encourage the recovery of serum lipid peroxidation injury; therefore, this may deserve widespread adoption and application.

Esclerodermia e Polimiosite em paciente evoluindo com calcinose severa: um relato de caso / Scleroderma and Polymyositis in a patient developing severe calcinosis: a case report

Introdução: As Doenças doTecido Conjuntivo são um grupo de doenças autoimunes ou idiopáticas, crônicas, de acometimento geralmente sistêmico e que podem, ou não, atacar o indivíduo de forma concomitante. O presente relato de caso apresenta a descrição de Esclerose Sistêmica e Polimiosite em uma mesma paciente. O fenômeno é conhecido como Sindrome de Overlap (presença simultânea de duas ou mais doenças do tecido conjuntivo, de natureza auto-imune em um paciente) e considerado raro. A Polimiosite e Dermatomiosite são doenças idiopáticas inflamatórias crônicas que afetam a musculatura estriada, a pele e outros órgãos. Esclerose sistêmica é outra doença não tão frequente, extremamente incapacitante pela sua repercussão multissistêmica, de evolução crônica e progressiva. As calcinoses, assim como fenômeno de Raynaud, mialgia, disfagia e queixas respiratórias, podem estar presentes em ambas as patologias, e no caso relatado não foi diferente.Métodos:Oestudo observacional descritivo relata o caso de uma paciente atendida pelo setor de reumatologia do Hospital do Servidor Público Municipal de São Paulo (HSPM), reunindo informações contidas em prontuários, do ano de 2014 até o presente momento. Discussão: A Dermatomiosite e a Síndrome de CREST, subtipos da esclerose sistêmica e das Miosites Inflamatórias, respectivamente, são doenças raras e de difícil diagnóstico devido a presença se sintomas em comum e passíveis de serem encontrados em outras comorbidades não auto-imunes. Seu tratamento é feito com imunossupressores e medicações voltadas para cada queixa clínica do paciente, a depender de uma boa investigação clínica e critérios diagnósticos fechados, evitando progressão acelerada e complicações clínicas. Conclusão: O tratamentoproposto para Esclerose sistêmica e Dermatomiosite já possui uma gama extensa de possibilidades farmacológicas e não-farmacológicas mas ainda sem protocolos específicos consensuais, sendo indicadas de acordo com a experiência pessoal do profissional, visando diminuição dos processos inflamatórios, recuperação de qualidade de vida e prevenção de complicações. Já o tratamento das calcinoses ainda não apresenta resultados satisfatórios, sendo propostos de acordo com a resposta clínica individual dos pacientes. Palavras-chave: Esclerose. Polimiosite. Dermatomiosite. Calcinose. Síndrome CREST.

Sputum Neutrophil Gelatinase-Associated Lipocalin as a Biomarker in Asthma-COPD Overlap.

BACKGROUND: Asthma COPD overlap (ACO) is a consensus-based phenotype having characteristics of both COPD and asthma. Distinguishing ACO from other diseases is even more important as it is related to low health-related quality of life, augmented exacerbation rate and hospital admission, a rapid deterioration in lung function, and increased morbidity and mortality. But it cannot be diagnosed explicitly based on spirometry tests, patient demographics, radiology, or by-sputum cytology. There is an unmet need to develop biomarkers. OBJECTIVES: To assess the role of sputum neutrophil gelatinase-associated lipocalin (NGAL) as a biomarker of ACO. To find the correlation between sputum NGAL levels with forced expiratory volume 1 (FEV1) and exacerbation rate in ACO. To find the correlation between sputum NGAL level with sputum neutrophils and eosinophils in ACO. MATERIALS AND METHODS: In this comparative correlational study, 180 subjects were enrolled into four groups with 45 patients each with asthma, COPD, ACO, and healthy nonsmokers respectively, respectively. After taking detailed history and demographics, sputum was analyzed for the differential count and NGAL. RESULTS: Asthma COPD overlap (ACO) cases had high sputum NGAL levels; the second was the COPD group, and the last in the case asthma group. Nonsmokers had notably lower readings than the diseased. Out of three, receiver operating characteristic (ROC) figures, the validity of NGAL was best in selecting patients of ACO than COPD and asthma. The area under curve (AUC) was highest for ACO and less than the acceptable limit for the remaining two. NGAL cut-off value of 2473 pg/mL had 80% sensitivity and 50% specificity for ACO. CONCLUSION: The present study investigated the sputum NGAL levels as a biomarker in ACO identified by the syndromic approach. Sputum NGAL, a biomarker associated with airway inflammation in airway diseases, was supportive of clinically differentiating ACO from asthma to COPD. How to cite this article: Babu A, Narayanswamy H, Baburao A. Sputum Neutrophil Gelatinase-Associated Lipocalin as a Biomarker in Asthma-COPD Overlap. J Assoc Physicians India 2023;71(9):34-38.

Does the asthma-chronic obstructive pulmonary disease overlap syndrome (ACOS) exist? A narrative review from epidemiology and practice.

Asthma and chronic obstructive pulmonary disease (COPD) have traditionally been approached as separate entities that must be researched and treated separately. There is growing recognition, however, that a substantial proportion of patients with obstructive lung disease have characteristics of both asthma and COPD (termed the asthma-COPD overlap syndrome (ACOS)). Lung disease experts have difficulty defining ACOS, and many still resist accepting the possibility that asthma and COPD may be linked. It is likely that practicing clinicians may be equally confused about how to identify and treat ACOS. This narrative review aims to clarify concepts of ACOS definition, argues that the best way to understand ACOS is to view the chronic lung disease process longitudinally rather than cross-sectionally, and presents evidence that ACOS can be the end result of the natural history of severe asthma. The review also points out the serious gaps in knowledge regarding therapy for ACOS and presents emerging data supporting the intracellular respiratory pathogen Chlamydia pneumoniae as a possible common etiologic agent in severe asthma and ACOS.

ß-Agonist exposure preferentially impacts lung macrophage cyclic AMP-related gene expression in asthma and asthma COPD overlap syndrome.

Bronchoalveolar lavage (BAL) samples from Severe Asthma Research Program (SARP) patients display suppression of a module of genes involved in cAMP-signaling pathways (BALcAMP) correlating with severity, therapy, and macrophage constituency. We sought to establish if gene expression changes were specific to macrophages and compared gene expression trends from multiple sources. Datasets included single-cell RNA sequencing (scRNA-seq) from lung specimens including a fatal exacerbation of severe Asthma COPD Overlap Syndrome (ACOS) after intense therapy and controls without lung disease, bulk RNA sequencing from cultured macrophage (THP-1) cells after acute or prolonged ß-agonist exposure, SARP datasets, and data from the Immune Modulators of Severe Asthma (IMSA) cohort. THP monocytes suppressed BALcAMP network gene expression after prolonged relative to acute ß-agonist exposure, corroborating SARP observations. scRNA-seq from healthy and diseased lung tissue revealed 13 cell populations enriched for macrophages. In severe ACOS, BALcAMP gene network expression scores were decreased in many cell populations, most significantly for macrophage populations (P < 3.9e-111). Natural killer (NK) cells and type II alveolar epithelial cells displayed less robust network suppression (P < 9.2e-8). Alveolar macrophages displayed the most numerous individual genes affected and the highest amplitude of modulation. Key BALcAMP genes demonstrate significantly decreased expression in severe asthmatics in the IMSA cohort. We conclude that suppression of the BALcAMP gene module identified from SARP BAL samples is validated in the IMSA patient cohort with physiological parallels observed in a monocytic cell line and in a severe ACOS patient sample with effects preferentially localizing to macrophages.

Occupation and subcategories of asthma: a population-based incident case-control study.

BACKGROUND: We hypothesised that occupational exposures differently affect subtypes of adult-onset asthma. OBJECTIVE: We investigated potential relations between occupation and three subtypes of adult asthma, namely atopic asthma, non-atopic asthma and asthma-COPD overlap syndrome (ACOS). METHODS: This is a population-based case-control study of incident asthma among working-age adults living in Pirkanmaa Hospital District in Southern Finland. The determinant of interest was occupation at the time of diagnosis of asthma or the job that the subject had quit due to respiratory symptoms. Asthma was divided into three mutually exclusive subtypes on the basis of any positive IgE antibody (atopic and non-atopic asthma) and presence of persistent airways obstruction in spirometry (ACOS). We applied unconditional logistic regression analysis to estimate adjusted OR (aOR), taking into account gender, age and smoking. RESULTS: The following occupational groups showed significantly increased risk of atopic asthma: chemical industry workers (aOR 15.76, 95% CI 2.64 to 94.12), bakers and food processors (aOR 4.69, 95% CI 1.18 to 18.69), waiters (aOR 4.67, 95% CI 1.40 to 15.56) and those unemployed (aOR 3.06, 95% CI 1.52 to 6.17). The following occupations showed clearly increased risk of non-atopic asthma: metal workers (aOR 8.37, 95% CI 3.77 to 18.59) and farmers and other agricultural workers (aOR 2.36, 95% CI 1.10 to 5.06). Some occupational groups showed statistically significantly increased OR of ACOS: electrical and electronic production workers (aOR 30.6, 95% CI 6.10 to 153.35), fur and leather workers (aOR 16.41, 95% CI 1.25 to 215.85) and those retired (aOR 5.55, 95% CI 1.63 to 18.97). CONCLUSIONS: Our results show that different occupations are associated with different subtypes of adult-onset asthma.

Pref-1 induced lung fibroblast differentiation by hypoxia through integrin α5ß1/ERK/AP-1 cascade.

Chronic obstructive asthma is characterized by airway fibrosis. Hypoxia and connective tissue growth factor (CTGF) play important roles in airway fibrosis. Preadipocyte factor-1 (Pref-1) participates in adipocyte differentiation and liver fibrosis. Herein, we investigated the role of Pref-1 in airway fibrosis in chronic obstructive asthma. We found that Pref-1 was overexpressed in lung tissues from chronic obstructive asthma patients compared to normal subjects. Extracellular matrix proteins were inhibited by Pref-1 small interfering (si)RNA in airway fibroblasts from chronic obstructive asthma patients. Furthermore, ovalbumin induced prominent Pref-1 expression and fibronectin coexpression. Hypoxia induced Pref-1 upregulation and its release into medium of WI-38 cells. Hypoxia-induced CTGF expression was inhibited by Pref-1 siRNA. We also found that Pref-1-stimulated fibrotic protein expressions were reduced by ATN-161, curcumin, U0126, and c-Jun siRNA in WI-38. Furthermore, ATN161 inhibited Pref-1-induced ERK phosphorylation, and ITGA5 siRNA inhibited c-Jun phosphorylation. Moreover, expression of CTGF, Fibronectin, α-SMA, and ERK and c-Jun phosphorylation were all increased in fibroblasts from patients with chronic obstructive asthma. Taken together, these results suggest that Pref-1 participates in airway fibrosis and hypoxia-induced CTGF expression via the integrin receptor α5ß1/ERK/AP-1 pathway.

The Plasma Levels of hsa-miR-19b-3p, hsa-miR-125b-5p, and hsamiR- 320c in Patients with Asthma, COPD and Asthma-COPD Overlap Syndrome (ACOS).

BACKGROUND: Bronchial Asthma (BA) and Chronic Obstructive Pulmonary Disease (COPD) are chronic airway inflammation diseases. In recent years, patients with signs of both BA and COPD have been assigned to a separate group as Asthma-COPD Overlap Syndrome (ACOS). Free-circulating plasma microRNAs are considered as potential biomarkers of pulmonology diseases, including BA, COPD, and ACOS. OBJECTIVE: This study aimed to investigate the expression level of free-circulating plasma microRNAs, hsa-miR-19b-3p, hsa-miR-125b-5p, and hsa-miR-320c in patients with BA, COPD and ACOS for the detection and validation of new microRNAs as biomarkers for chronic lung diseases. METHODS: The relative expression levels of 720 microRNAs were evaluated by Real Time-Polymerase Chain Reaction (RT-PCR) in patients with COPD and BA. Three upregulated microRNAs (hsa-miR-19b-3p, hsa-miR-125b-5p and hsa-miR-320c) were selected for further study. The obtained data were analyzed using the microRNA PCR Array Data Analysis tool. The sensitivity and specificity were estimated using the area under the Receiver Operating Characteristics curve (ROC). RESULTS: The expression level of free-circulating hsa-miR-19b-3p was decreased in the blood plasma of patients with BA and ACOS, and increased in patients with COPD. hsa-miR-125b-5p was downregulated in the blood plasma of patients with COPD and upregulated in patients with BA and ACOS. hsa-miR-320c was downregulated in the blood plasma of patients with BA, and upregulated in patients with COPD and ACOS. The ROC curves of patients with BA for hsa-miR-19b-3p, patients with ACOS for hsa-miR-125b-5p, and patients with COPD for hsa-miR-320c revealed the probability of them as valuable biomarkers with AUCs of 0.824, 0.825, and 0.855, respectively. CONCLUSION: Our study revealed three promising biomarkers for the diagnosis of COPD, BA and ACOS.

Comparison of clinical features and outcomes for asthma-COPD overlap syndrome vs. COPD patients: a systematic review and meta-analysis.

OBJECTIVE: The aim of this study was to review evidence to determine whether "pure" chronic obstructive pulmonary disease (COPD) patients without a history of asthma differ in the clinical characteristics, severity of airflow limitation, and clinical outcomes compared to patients with Asthma-COPD Overlap Syndrome (ACOS). MATERIALS AND METHODS: An electronic search was performed in the MEDLINE, EMBASE, SCOPUS and Web of Science databases to identify comparing the clinical characteristics and outcomes between ACOS and "pure" COPD. The included studies were subjected to meta-analysis and risk of bias assessment using ROBINS-E tool. Eleven observational studies were included. RESULTS: The results of the meta-analysis showed increased expression of lung function parameters like forced expiration volume (FEV) at 1 sec{mean difference (MD) 2.36; 95% CI [0.05,4.66] ; p=0.004; I2= 72%} and clinical symptoms in terms of fever {Relative Risk (RR) 0.34, p<0.0001}, wheezing {RR 0.39, p<0.0001} and dyspnea {RR 0.53, p<0.0001}. The comorbidities associated with ACOS patients were similar to that found in patients with "pure" COPD. Interestingly, higher body mass index (BMI) was found in patients with ACOS (MD -0.73 95% CI [-1.06, -0.41], p<0.0001. CONCLUSIONS: The result showed higher risk in onset of frequent acute exacerbations, severe exacerbations requiring hospitalization and higher number of exacerbations experienced per year in ACOS patients. Within the limitations of the review, ACOS can be regarded as separate entity of co-existence which is classically associated with higher BMI, worsened lung function parameters and exacerbations with a varying degree of clinical symptoms.

Lavado broncoalveolar y diagnóstico de enfermedades respiratorias bajas / Bronchoalveolar lavage and the diagnosis of lower respiratory infections

Las patologías respiratorias son una de las principales causas de enfermedad y muerte. En las estimaciones hechas por la Organización Mundial de la Salud (OMS) entre los años 2000 y 2019, la enfermedad pulmonar obstructiva crónica y las infecciones de las vías respiratorias inferiores fueron la tercera y cuarta causa de muerte, respectivamente, y la primera cuando el análisis se hacía únicamente con las enfermedades transmisibles, tanto antes de la pandemia por SARS-CoV-2 (COVID-19), como durante esta. Para modificar su impacto en la salud de la población, es importante, además de mantener y mejorar las actividades encaminadas a su prevención, establecer diagnósticos y tratamientos oportunos, certeros y eficaces

Asthma-chronic obstructive pulmonary disease overlap syndrome.

Overlap of asthma and chronic obstructive lung disease (ACO) in patients with obstructive lung disease is growing in recognition, though there is no consistent agreement on the diagnostic criteria for the disease process. Patients with ACO have distinct clinical characteristics and trajectories, which are representative of a heterogenous, multifactorial, and incompletely understood inflammatory pathophysiology. Current treatment strategies are focused on titration of inhaled therapies such as long-acting bronchodilators, with increasing interest in the use of targeted biologic therapies aimed at the underlying inflammatory mechanisms. Future directions for research will focus on elucidating the varied inflammatory signatures leading to ACO, the development of consistent diagnostic criteria and biomarkers of disease, and improving the clinical management with an eye toward targeted therapies.

Current situation of asthma-COPD overlap in Chinese patients older than 40 years with airflow limitation: a multicenter, cross-sectional, non-interventional study.

BACKGROUND AND AIMS: Asthma-chronic obstructive pulmonary disease (COPD) overlap (ACO) is poorly recognized in China. Our study determined the distribution of ACO and its clinical characteristics among patients (aged ⩾40 years) with airflow limitation at Chinese tertiary hospitals. METHODS: This cross-sectional, non-interventional study (NCT02600221), conducted between December 2015 and October 2016 in 20 Tier-3 Chinese hospitals, included patients aged ⩾40 years with post-bronchodilator (BD) FEV1/FVC <0.7. The primary variable was distribution of ACO in adults with post-BD forced expiratory volume /forced vital capacity (FEV1/FVC) <0.7 based on Global Initiative for Chronic Obstructive Lung Disease (GOLD) 2015 and 2017 reports. Other variables included determination of characteristics of ACO and its clinical recognition rate. RESULTS: In 2003 patients (mean age 62.30 ± 9.86 years), distribution of ACO, COPD and asthma were 37.40%, 48.50% and 14.10%, respectively. Proportions of patients with A, B, C and D grouping were 11.70%, 31.00%, 6.90% and 50.30% as per GOLD 2017, whereas they were 15.10%, 51.10%, 3.60% and 30.20% as per GOLD 2015. Similar clinical symptoms were reported in all three groups. A higher percentage of ACO patients presented with dyspnea, wheezing and chest tightness. Compared with the COPD group, a greater proportion of ACO patients reported wheezing (74.6% and 65.40%), while a lower proportion in the ACO group reported cough (79.40% versus 82.70%) and expectoration (76.50% versus 81.60%). Blood eosinophil count ⩾0.3 × 109/L was observed in 34.6% of ACO patients. The clinical recognition rate of ACO was 31.4%. CONCLUSION: Despite ACO affecting two-fifths of the study population, the initial diagnosis rate was low at 6% in China, thus warranting concerted efforts to improve ACO diagnosis. CLINICALTRIALS.GOV: [ClinicalTrials.gov identifier: NCT02600221] registered 22 October 2015, https://clinicaltrials.gov/ct2/show/NCT02600221The reviews of this paper are available via the supplemental material section.

Asthma-Chronic Obstructive Pulmonary Disease Overlap.

Asthma-chronic obstructive pulmonary disease (COPD) overlap (ACO) defines a subgroup of patients with asthma who have persistent airflow obstruction or patients with COPD who may exhibit variable airflow limitation and/or evidence of type 2 inflammation. Additional investigations are needed to determine whether ACO represents a distinct disorder with unique underlying pathophysiology, whether ACO patients should be managed differently from those with asthma or COPD, and whether the diagnosis affects long-term outcomes. This article presents the data about the clinical features of ACO, the current information regarding the underlying pathophysiology of the syndrome, and current understanding of therapeutic options.

A COVID-19 patient with intense burning pain.

A woman in her forties with asthma and COPD was admitted to a general medical floor with respiratory symptoms, body aches, and anosmia. Reverse transcription polymerase chain reaction detected severe acute respiratory syndrome coronavirus-2. Admission labs, including biomarkers of the systemic immunological dysfunction seen in many cases of coronavirus disease 2019 (COVID-19), were within normal ranges. On the second day of admission, she developed neck and back pain that was constant, burning in quality, and exacerbated by light touch and heat. Wearing clothing caused pain and interfered with her sleep. The area was tender to light finger stroke. The patient was given acetaminophen, NSAIDs, and opioids with no relief of pain. However, gabapentin was effective. At follow-up 1 month later, her symptoms were improved and still relieved by gabapentin. Neuropathic pain was seen in over 2% of COVID-19 patients in one observational study. The pain seen in our case was bilateral, involved an area innervated by multiple levels of spinal nerves, and was limited to the back. While it is rare, a significant number of COVID-19 patients are afflicted by neuropathic pain, and our case illustrates that gabapentin may be effective.

Visual and Quantitative Assessments of Regional Xenon-Ventilation Using Dual-Energy CT in Asthma-Chronic Obstructive Pulmonary Disease Overlap Syndrome: A Comparison with Chronic Obstructive Pulmonary Disease.

OBJECTIVE: To assess the regional ventilation in patients with asthma-chronic obstructive pulmonary disease (COPD) overlap syndrome (ACOS) using xenon-ventilation dual-energy CT (DECT), and to compare it to that in patients with COPD. MATERIALS AND METHODS: Twenty-one patients with ACOS and 46 patients with COPD underwent xenon-ventilation DECT. The ventilation abnormalities were visually determined to be 1) peripheral wedge/diffuse defect, 2) diffuse heterogeneous defect, 3) lobar/segmental/subsegmental defect, and 4) no defect on xenon-ventilation maps. Emphysema index (EI), airway wall thickness (Pi10), and mean ventilation values in the whole lung, peripheral lung, and central lung areas were quantified and compared between the two groups using the Student's t test. RESULTS: Most patients with ACOS showed the peripheral wedge/diffuse defect (n = 14, 66.7%), whereas patients with COPD commonly showed the diffuse heterogeneous defect and lobar/segmental/subsegmental defect (n = 21, 45.7% and n = 20, 43.5%, respectively). The prevalence of ventilation defect patterns showed significant intergroup differences (p < 0.001). The quantified ventilation values in the peripheral lung areas were significantly lower in patients with ACOS than in patients with COPD (p = 0.045). The quantified Pi10 was significantly higher in patients with ACOS than in patients with COPD (p = 0.041); however, EI was not significantly different between the two groups. CONCLUSION: The ventilation abnormalities on the visual and quantitative assessments of xenon-ventilation DECT differed between patients with ACOS and patients with COPD. Xenon-ventilation DECT may demonstrate the different physiologic changes of pulmonary ventilation in patients with ACOS and COPD.