Asthma, chronic obstructive pulmonary disease, and mortality in the U.S. population

Assessment of functional diversities in patients with Asthma, COPD, Asthma-COPD overlap, and Cystic Fibrosis (CF)

The objectives of the present study were to evaluate the discriminating power of spirometric and plethysmographic lung function parameters to differenciate the diagnosis of asthma, ACO, COPD, and to define functional characteristics for more precise classification of obstructive lung diseases. From the databases of 4 centers, a total of 756 lung function tests (194 healthy subjects, 175 with asthma, 71 with ACO, 78 with COPD and 238 with CF) were collected, and gradients among combinations of target parameters from spirometry (forced expiratory volume one second: FEV1; FEV1/forced vital capacity: FEV1/FVC; forced expiratory flow between 25-75% FVC: FEF25-75), and plethysmography (effective, resistive airway resistance: sReff; aerodynamic work of breathing at rest: sWOB), separately for in- and expiration (sReffIN, sReffEX, sWOBin, sWOBex) as well as static lung volumes (total lung capacity: TLC; functional residual capacity: FRCpleth; residual volume: RV), the control of breathing (mouth occlusion pressure: P0.1; mean inspiratory flow: VT/TI; the inspiratory to total time ratio: TI/Ttot) and the inspiratory impedance (Zinpleth = P0.1/VT/TI) were explored. Linear discriminant analyses (LDA) were applied to identify discriminant functions and classification rules using recursive partitioning decision trees. LDA showed a high classification accuracy (sensitivity and specificity > 90%) for healthy subjects, COPD and CF. The accuracy dropped for asthma (~70%) and even more for ACO (~60%). The decision tree revealed that P0.1, sRtot, and VT/TI differentiate most between healthy and asthma (68.9%), COPD (82.1%), and CF (60.6%). Moreover, using sWOBex and Zinpleth ACO can be discriminated from asthma and COPD (60%). Thus, the functional complexity of obstructive lung diseases can be understood, if specific spirometric and plethysmographic parameters are used. Moreover, the newly described parameters of airway dynamics and the central control of breathing including Zinpleth may well serve as promising functional marker in the field of precision medicine.

Sex differences in comorbidities and mortality risk among patients with chronic obstructive pulmonary disease: a study based on NHANES data

BACKGROUND

Patients with chronic obstructive pulmonary disease (COPD) commonly have coexisting comorbidities that contribute to higher exacerbation frequency, poorer health status, and increased all-cause mortality; however, there are only a few studies available on the sex discrepancy in the comorbidity distribution and outcomes among COPD patients, and there is limited information about the discrepancy in all-cause mortality between men and women.

METHODS

Based on data from the U.S. National Health and Nutrition Examination Survey conducted between 2007 and 2012, we compared participants aged 40-79 years with spirometry-defined COPD to compare the prevalence of comorbidities between men and women. The survival of the subjects was documented, and the sex discrepancy was determined using Kaplan-Meier analysis. Comorbidities and all-cause mortality were analyzed by using a Cox proportional hazards model to determine their strength of association in different sex groups.

RESULTS

Compared to men, women had a significantly higher prevalence of asthma (OR 1.93, 95% CI 1.46 to 2.57, p < 0.001) and arthritis (OR 1.77, 95% CI 1.39 to 2.24, p < 0.001). Women had a significantly lower prevalence of coronary heart disease (OR 0.48, 95% CI 0.27 to 0.87, p = 0.015) and gout (OR 0.42, 95% CI 0.25 to 0.67, p = 0.001). Kaplan-Meier analysis revealed that compared with that of the female group, the survival rate of the male group was significantly lower (p < 0.001). Among men, the presence of anemia (HR 2.38, [95% CI 1.52-3.73], p < 0.001), gout (HR 1.55, [95% CI 1.04-2.30], p = 0.029) and congestive heart failure comorbidities (HR 1.85, [95% CI 1.12-3.04] p = 0.016) was associated with a higher risk of mortality; among women, the presence of anemia (HR 2.21, [95% CI 1.17-4.20], p = 0.015) and stroke (HR 2.04, [95% CI 1.07-3.88], p = 0.031) comorbidities was associated with a higher risk of mortality after adjusting for age, race/Hispanic status, BMI, smoking status, FEV1% predicted and prevalent comorbidities.

CONCLUSIONS

COPD-related comorbidities and all-cause mortality were discrepant between men and women, and men had poorer survival than women in the nationally representative data that were analyzed.

[Diagnosis and treatment of asthma: a guideline for respiratory specialists 2023 - published by the German Respiratory Society (DGP) e. V.]

The management of asthma has fundamentally changed during the past decades. The present guideline for the diagnosis and treatment of asthma was developed for respiratory specialists who need detailed and evidence-based information on the new diagnostic and therapeutic options in asthma. The guideline shows the new role of biomarkers, especially blood eosinophils and fractional exhaled NO (FeNO), in diagnostic algorithms of asthma. Of note, this guideline is the first worldwide to announce symptom prevention and asthma remission as the ultimate goals of asthma treatment, which can be achieved by using individually tailored, disease-modifying anti-asthmatic drugs such as inhaled steroids, allergen immunotherapy or biologics. In addition, the central role of the treatment of comorbidities is emphasized. Finally, the document addresses several challenges in asthma management, including asthma treatment during pregnancy, treatment of severe asthma or the diagnosis and treatment of work-related asthma.

Air pollution associated with incidence and progression trajectory of chronic lung diseases: a population-based cohort study

BACKGROUND

No prior study has examined the effects of air pollution on the progression from healthy to chronic lung disease, subsequent chronic lung multimorbidity and further to death.

METHODS

We used data from the UK Biobank of 265 506 adults free of chronic lung disease at recruitment. Chronic lung multimorbidity was defined as the coexistence of at least two chronic lung diseases, including asthma, chronic obstructive pulmonary disease and lung cancer. The concentrations of air pollutants were estimated using land-use regression models. Multistate models were applied to assess the effect of air pollution on the progression of chronic lung multimorbidity.

RESULTS

During a median follow-up of 11.9 years, 13 863 participants developed at least one chronic lung disease, 1055 developed chronic lung multimorbidity and 12 772 died. We observed differential associations of air pollution with different trajectories of chronic lung multimorbidity. Fine particulate matter showed the strongest association with all five transitions, with HRs (95% CI) per 5 µg/m3 increase of 1.31 (1.22 to 1.42) and 1.27 (1.01 to 1.57) for transitions from healthy to incident chronic lung disease and from incident chronic lung disease to chronic lung multimorbidity, and 1.32 (1.21 to 1.45), 1.24 (1.01 to 1.53) and 1.91 (1.14 to 3.20) for mortality risk from healthy, incident chronic lung disease and chronic lung multimorbidity, respectively.

CONCLUSION

Our study provides the first evidence that ambient air pollution could affect the progression from free of chronic lung disease to incident chronic lung disease, chronic lung multimorbidity and death.

Asthma, chronic obstructive pulmonary disease, and asthma-COPD overlap among US working adults

BACKGROUND

Asthma-COPD overlap (ACO) is a respiratory condition with more severe respiratory symptoms, poorer quality of life, and increased hospital admissions compared with asthma or COPD alone.

OBJECTIVES

Estimate asthma, chronic obstructive pulmonary disease (COPD), and ACO prevalence among workers by industry and occupation and assess physical and mental health status, healthcare utilization, among workers with ACO.

METHODS

The 2014-2018 National Health Interview Survey (NHIS) data for working adults aged ≥18 years employed (sample n = 99,424) in the 12 months prior to the survey were analyzed. Age-adjusted ACO, COPD and asthma prevalence and prevalence ratios adjusted for age, sex, race and smoking status were estimated.

RESULTS

During 2014-2018, of the estimated 166 million (annual average) US workers, age-adjusted asthma, COPD, and ACO prevalence was 6.9%, 4.0%, and 1.1%, respectively. ACO prevalence was highest among workers aged ≥65 years (2.0%), females (1.6%), current smokers (1.9%), those living below the federal poverty level (2.3%), and workers in the accommodation and food services (1.6%) industry and personal care and service (2.3%) occupations. Workers with ACO had more frequent (p < 0.05) physician office visits, emergency department visits; and were more likely to be in poorer mental health, obese, have more lost workdays, more bed days, and comorbidities compared to workers with asthma alone and workers with COPD alone.Conclusion: Higher ACO prevalence among worker groups and increased healthcare utilization underscores the need for early identification of asthma and COPD, assessment of potential workplace exposures, and implementation of tailored interventions to reduce ACO among working adults.

Functional Predictors Discriminating Asthma-COPD Overlap (ACO) from Chronic Obstructive Pulmonary Disease (COPD)

Background

A significant proportion of patients with obstructive lung disease have clinical and functional features of both asthma and chronic obstructive pulmonary disease (COPD), referred to as the asthma–COPD overlap (ACO). The distinction of these phenotypes, however, is not yet well-established due to the lack of defining clinical and/or functional criteria. The aim of our investigations was to assess the discriminating power of various lung function parameters on the assessment of ACO.

Methods

From databases of 4 pulmonary centers, a total of 540 patients (231 males, 309 females), including 372 patients with asthma, 77 patients with ACO and 91 patients with COPD, were retrospectively collected, and gradients among combinations of explanatory variables of spirometric (FEV₁, FEV₁/FVC, FEF_25-75), plethysmographic (sR_eff, sG_eff, the aerodynamic work of breathing at rest; sWOB), static lung volumes, including trapped gases and measurements of the carbon monoxide transfer (DL_CO, K_CO) were explored using multiple factor analysis (MFA). The discriminating power of lung function parameters with respect to ACO was assessed using linear discriminant analysis (LDA).

Results

LDA revealed that parameters of airway dynamics (sWOB, sR_eff, sG_eff) combined with parameters of static lung volumes such as functional residual capacity (FRC_pleth) and trapped gas at FRC (V_TG^FRC) are valuable and potentially important tools discriminating between asthma, ACO and COPD. Moreover, sWOB significantly contributes to the diagnosis of obstructive airway diseases, independent from the state of pulmonary hyperinflation, whilst the diffusion capacity for carbon monoxide (DL_CO) significantly differentiates between the 3 diagnostic classes.

Conclusion

The complexity of COPD with its components of interaction and their heterogeneity, especially in discrimination from ACO, may well be differentiated if patients are explored by a whole set of target parameters evaluating, interactionally, flow limitation, airway dynamics, pulmonary hyperinflation, small airways dysfunction and gas exchange disturbances assessing specific functional deficits.

Epidemiology of Asthma-Chronic Obstructive Pulmonary Disease Overlap

Asthma COPD Overlap has consistently reported to be associated with an increase burden of disease but the impact on lung function decline and mortality varies by study. The prevalence increases with age but the relationship with gender also varies with the study population. The variability in the prevalence and clinical characteristics of ACO is linked to differences in how chronic obstructive pulmonary disease (COPD) and asthma are defined, including diagnostic criteria (spirometry-based vs. clinical or symptom-based diagnoses vs. claims data), the population studied, the geographic region and environment and a consensus approach to the diagnosis of ACO is needed to allow meaningful and consistent epidemiologic information to be generated about this condition.

Association between annual change in FEV1 and comorbidities or impulse oscillometry in chronic obstructive pulmonary disease

Background

Chronic obstructive pulmonary disease (COPD) is characterized by persistent respiratory symptoms and airflow limitation. The decline in forced expiratory volume in one second (FEV₁) is considered to be one of the most important outcome measures for evaluating disease progression. However, the only intervention proven to improve COPD prognosis is smoking cessation. This study therefore investigated the factors associated with annual FEV₁ decline in COPD.

Methods

This retrospective study followed up 65 patients treated for COPD for 5 years: 13 current smokers and 52 former smokers, 25 with pneumonia, 24 with asthma, 18 with cancer, and 17 with cardiovascular disease. The patients were divided into groups based on clinical cutoff parameters of the impulse oscillometry system (IOS): 11 high and 54 low R5, 8 high and 57 low R20, 21 high and 44 low R5–R20, 26 high and 39 low X5, 38 high and 27 low Fres, and 36 high and 29 low AX. We investigated whether the decline in FEV₁ was associated with comorbidities and IOS parameters.

Results

The annual change in FEV₁ over 5 years was significantly affected by smoking status (current − 66.2 mL/year vs. former − 5.7 mL/year, p < 0.01), pneumonia (with − 31.5 mL/year vs. without − 8.9 mL/year, p < 0.05), asthma (with − 30.2 mL/year vs. − 10.8 mL/year, p < 0.01), but not by cancer and cardiovascular disease. In the groups defined by IOS results, only the high AX group had significantly more annual decline in FEV₁ and %FEV₁ than the low AX group (− 22.1 vs. − 12.8, p < 0.05 and − 0.20 vs. 0.40, p < 0.05, respectively).

Conclusions

Continuing smoking as well as complications in pneumonia and asthma would be risk factors for the progression of COPD. AX might be a suitable parameter to predict the prognosis of patients with COPD.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12890-022-01980-6.

Genetic Associations and Architecture of Asthma-COPD Overlap

BACKGROUND

Some people have characteristics of both asthma and COPD (asthma-COPD overlap), and evidence suggests they experience worse outcomes than those with either condition alone.

RESEARCH QUESTION

What is the genetic architecture of asthma-COPD overlap, and do the determinants of risk for asthma-COPD overlap differ from those for COPD or asthma?

STUDY DESIGN AND METHODS

We conducted a genome-wide association study in 8,068 asthma-COPD overlap case subjects and 40,360 control subjects without asthma or COPD of European ancestry in UK Biobank (stage 1). We followed up promising signals (P < 5 × 10^-6) that remained associated in analyses comparing (1) asthma-COPD overlap vs asthma-only control subjects, and (2) asthma-COPD overlap vs COPD-only control subjects. These variants were analyzed in 12 independent cohorts (stage 2).

RESULTS

We selected 31 independent variants for further investigation in stage 2, and discovered eight novel signals (P < 5 × 10^-8) for asthma-COPD overlap (meta-analysis of stage 1 and 2 studies). These signals suggest a spectrum of shared genetic influences, some predominantly influencing asthma (FAM105A, GLB1, PHB, TSLP), others predominantly influencing fixed airflow obstruction (IL17RD, C5orf56, HLA-DQB1). One intergenic signal on chromosome 5 had not been previously associated with asthma, COPD, or lung function. Subgroup analyses suggested that associations at these eight signals were not driven by smoking or age at asthma diagnosis, and in phenome-wide scans, eosinophil counts, atopy, and asthma traits were prominent.

INTERPRETATION

We identified eight signals for asthma-COPD overlap, which may represent loci that predispose to type 2 inflammation, and serious long-term consequences of asthma.

Association Between Asthma and All-Cause Mortality and Cardiovascular Disease Morbidity and Mortality: A Meta-Analysis of Cohort Studies

Background

Asthma and cardiovascular disease (CVD) share many risk factors. Previous meta-analyses indicated that asthma is associated with an increased risk of CVD and all-cause mortality, but these studies were limited by unstandardized search strategies and the number of articles included.

Objective

We sought to systematically synthesize evidence investigating the impact of asthma on all-cause mortality and CVD morbidity and mortality.

Methods

We searched in PubMed and EMBASE for observational cohort studies (inception dates to November 10, 2021) that had both asthma groups and control groups. We also manually searched the reference lists of correlative articles to include other eligible studies. Data for associations between asthma and all-cause mortality and CVD morbidity and mortality were needed.

Results

We summarized the findings from 30 cohort studies comprising 4,157,823 participants. Asthma patients had increased CVD morbidity [relative risk (RR) = 1.28, 95% confidence interval (CI) = 1.16–1.40] and increased CVD mortality (RR = 1.25, 95% CI = 1.14–1.38). Asthma patients also had increased risk of all-cause mortality (RR = 1.38, 95% CI = 1.07–1.77). In subgroup analyses, female asthma patients had a higher risk of CVD morbidity and all-cause mortality than male asthma patients, and late-onset asthma patients had a higher risk of CVD morbidity than early-onset asthma patients.

Conclusion

Asthma patients have increased risk of all-cause mortality and CVD morbidity and mortality. This information reminds clinicians to be aware of the risk of CVD and all-cause mortality in asthma patients.

Systematic Review Registration

http://www.crd.york.ac.uk/PROSPERO/, PROSPERO, identifier: CRD 42021290082.

Advances in microfluidics devices and its applications in personalized medicines

Microfluidics is an exponentially growing area and is being used for numerous applications from basic science to advanced biotechnology and medicines. Microfluidics provides a platform to the research community for studying and building new strategies for the diagnosis and therapeutics applications. In the last decade, microfluidic have enriched the field of diagnostics by providing new solutions which was not possible with conventional detection and treatment methods. Microfluidics has the ability to precisely control and perform high-throughput functions. It has been proven as an efficient and rapid method for biological sample preparation, analysis and controlled drug delivery system. Microfluidics plays significant role in personalized medicine. These personalized medicines are used for medical decisions, practices and other interventions as well as for individual patients based on their predicted response or risk of disease. This chapter highlights microfluidics in developing personalized medical applications for its applications in diseases such as cancer, cardiovascular disease, diabetes, pulmonary disease and several others.

Respiratory-related death in individuals with incident asthma and COPD: a competing risk analysis

Background

Distinguishing between mortality attributed to respiratory causes and other causes among people with asthma, COPD, and asthma-COPD overlap (ACO) is important. This study used electronic health records in England to estimate excess risk of death from respiratory-related causes after accounting for other causes of death.

Methods

We used linked Clinical Practice Research Datalink (CPRD) primary care and Office for National Statistics mortality data to identify adults with asthma and COPD from 2005 to 2015. Causes of death were ascertained using death certificates. Hazard ratios (HR) and excess risk of death were estimated using Fine-Gray competing risk models and adjusting for age, sex, smoking status, body mass index and socioeconomic status.

Results

65,021 people with asthma and 45,649 with COPD in the CPRD dataset were frequency matched 5:1 with people without the disease on age, sex and general practice. Only 14 in 100,000 people with asthma are predicted to experience a respiratory-related death up to 10 years post-diagnosis, whereas in COPD this is 98 in 100,000. Asthma is associated with an 0.01% excess incidence of respiratory related mortality whereas COPD is associated with an 0.07% excess. Among people with asthma-COPD overlap (N = 22,145) we observed an increased risk of respiratory-related death compared to those with asthma alone (HR = 1.30; 95% CI 1.21–1.40) but not COPD alone (HR = 0.89; 95% CI 0.83–0.94).

Conclusions

Asthma and COPD are associated with an increased risk of respiratory-related death after accounting for other causes; however, diagnosis of COPD carries a much higher probability. ACO is associated with a lower risk compared to COPD alone but higher risk compared to asthma alone.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12890-022-01823-4.

Prevalence of asthma—chronic obstructive pulmonary disease overlap in patients with airflow limitation

Background

Asthma-COPD overlap (ACO) according to GINA and GOLD is not a single disease and is described by persistent airflow limitation with several features usually associated with asthma and several features usually associated with COPD. Some different protocols were proposed to diagnose ACO, besides those reported in GINA and GOLD guidelines. Despite the discrepancy between all the proposed diagnostic protocols, the diagnosis of ACO is still worthy as it may lead to a more appropriate treatment plan. In Egypt, prevalence of ACO is hardly estimated due to lack of database of patients. Our aim of work was to detect the prevalence of ACO in patients diagnosed as having a chronic airflow limiting disease.

Results

In asthma group (75 patients), 53.3% (40 patients) were diagnosed as ACO with 3 statistically significant favoring diagnostic criteria; post-BDR test FEV1/FVC < 70%, longer disease duration, and sputum neutrophilia ≥ 57%. While in COPD group (75 patients), 42.7% (32 patients) were diagnosed as ACO with four statistically significant favoring diagnostic criteria; higher BDR, presence of personal history of either asthma or atopy and sputum eosinophils > 1%.

Conclusions

ACO has an underestimated prevalence among those diagnosed with either asthma or COPD. More consensus guidelines are needed to focus on the more effective and the more practical criteria to diagnose such hidden disease.

Long-term Natural History of Severe Asthma Exacerbations and Their Impact on the Disease Course

Rationale

The long-term natural history of asthma in terms of successive severe exacerbations and the influence of each exacerbation on the course of the disease is not well studied.

Objectives

To investigate the long-term natural history of asthma among patients who are hospitalized for asthma for the first time in terms of the risk of future severe exacerbations and heterogeneity in this risk across patients.

Methods

Using the administrative health databases of British Columbia, Canada (January 1, 1997 to March 31, 2016), we created an incident cohort of patients with at least one asthma exacerbation that required inpatient care. We estimated the 5-year cumulative incidence of severe exacerbations after successive numbers of previous events. We used a joint frailty model to investigate the extent of between-individual variability in exacerbation risk and the associations of each exacerbation with the rate of subsequent events. Analyses were conducted separately for pediatric (<14 years old) and adult (⩾14 years old) patients.

Results

Analyses were based on 3,039 pediatric (mean age at baseline, 6.4; 35% female) and 5,442 (mean age at baseline, 50.8; 68% female) adult patients. The 5-year rates of severe exacerbations after the first three events were 0.16, 0.29, and 0.35 for the pediatric group, and 0.14, 0.33, and 0.49 for the adult group. Both groups exhibited substantial variability in patient-specific risks of exacerbation: the mid-95% interval of 5-year risk of experiencing a severe exacerbation ranged from 11% to 24% in pediatric patients and from 8% to 40% in adult patients. After controlling for potential confounders, the first follow-up exacerbation was associated with an increase of 79% (95% confidence interval [CI], 11–189%) in the rate of subsequent events in the pediatric group, whereas this increase was 188% (95% CI, 35–515%) for the adult group. The effects of subsequent exacerbations were not statistically significant.

Conclusions

After the first severe exacerbation, the risk of subsequent events is substantially different among patients. The number of previous severe exacerbations carries nuanced prognostic information about future risk. Our results suggest that severe exacerbations in the early course of asthma detrimentally affect the course of the disease and risk of subsequent exacerbations.

The Value of Impulse Oscillometric Parameters and Quantitative HRCT Parameters in Differentiating Asthma-COPD Overlap from COPD

Purpose

To evaluate the value of impulse oscillometry (IOS) and quantitative HRCT parameters for differentiating asthma-COPD overlap (ACO) in COPD patients.

Patients and Methods

We enrolled 44 controls and 66 COPD patients, divided into the pure COPD group (n=40) and the ACO group (n=26). Spearman correlation analysis was utilized to assess the relationship between the quantitative HRCT and IOS parameters. A binary logistic regression analysis was performed to analyze the associations between the different variables and the risk of ACO. Receiver operating characteristic (ROC) curves were employed to identify the optimal cutoff and assess the diagnostic value of relative volume change -856 HU to -950 HU (RVC_{-856 to -950}), decrease in the resistance from 5 Hz to 20 Hz (R5-R20) and their combination in predicting ACO. Bootstrapping validation was used to evaluate the internal validation. The concordance index (C-index) and calibration plot were calculated to assess the discrimination and calibration of the prediction model.

Results

Binary logistic regression analysis indicated that RVC_{-856 to -950} and the IOS parameters (R5-R20, R5, X5) were independently correlated with a higher risk of developing ACO after adjusting for age, sex, body mass index (BMI), history of smoking, exacerbation and atopy or allergic rhinitis. A correlation analysis showed a good correlation between the pulmonary function parameters and RVC_{-856 to -950}, with a weaker correlation with the % area of low attenuation (LAA%) in ACO patients. Combining RVC_{-856 to -950} and R5-R20 to predict ACO, the AUC was 0.909, and the optimal cutoff value was >-0.62 for RVC_{-856 to -950} and >0.09 for R5-R20. Good calibration and favorable discrimination were displayed with a higher C-index.

Conclusion

More serious small airway impairment exists in ACO patients. The combination of RVC_{-856 to -950} and R5-R20 could be applied to differentiate ACO from COPD patients.

Current Knowledge of Asthma-COPD Overlap (ACO) Genetic Risk Factors, Characteristics, and Prognosis

Asthma-COPD overlap (ACO) is a newly identified phenotype of chronic obstructive airway diseases with shared asthma and COPD features. Patients with ACO are poorly defined, and some evidence suggests that they have worse health outcomes and greater disease burden than patients with COPD or asthma. Generally, there is no evidence-based and universal definition for ACO; several consensus documents have provided various descriptions of the phenotype. In addition, the mechanisms underlying the development of ACO are not fully understood. Whether ACO is a distinct clinical entity with its particular discrete genetic determinant different from asthma and COPD alone or an intermediate phenotype with overlapping genetic markers within asthma and COPD spectrum of obstructive airway disease remains unproven. This review summarizes the current knowledge of the genetic risk factors, characteristics, and prognosis of ACO.

Health expenditures of asthma-COPD overlap in Northern Jordan

Objective

To investigate the characteristics and medical expenditures of patients with Asthma- chronic obstructive pulmonary disease (COPD) overlap (ACO) compared to asthma and COPD patients.

Methods

This was a retrospective cohort study involving patients diagnosed with ACO, asthma or COPD as of January 2016. Medical records for patients attending King Abdullah University Hospital (KAUH), in northern Jordan, during the years 2015–2016 were used to identify eligible patients and all relevant clinical characteristics. Both respiratory and all-cause charges were extracted from KAUH billing system during the year 2016. Total, inpatient, outpatient, and pharmacy charges were described and compared across the three disease categories. Charges were measured in Jordanian Dinar (JOD, equal to 1.41 US Dollar).

Results

Of a total of 761, 87 ACO patients, 494 asthmatic patients and 180 COPD patients were identified and included in this study. The average total respiratory-related charges were significantly higher in patients with ACO compared to patients with asthma (601.4 versus 354.3 JODs; P value < 0.001). Average all-cause charges were higher in case of ACO and COPD compared to patients with asthma (1830.8 and 1705.4 versus 1251.7 JODs; P value < 0.001). ACO was a significant predictor of higher respiratory and all-cause related charges. Respiratory charges were also higher in older patients and those with higher disease severity.

Conclusions

ACO is a risk factor for incurring higher health expenditures in Jordan. Higher respiratory expenditures are also associated with older ages and higher disease severity.

Concurrent asthma and chronic obstructive pulmonary disease in adult ED patients: A national perspective

OBJECTIVES

Emergency department (ED) visits for Asthma and Chronic Obstructive Pulmonary Disease (COPD) are common. The designation of Asthma-COPD overlap (ACO) has been used to describe patients with features of both diseases. Studies show that ACO patients may be at increased risk of poor outcomes relative to patients with either disease alone. We sought to characterize ED visits and ED-related outcomes of patients with ACO compared to patients with Asthma or COPD alone.

METHODS

We conducted a secondary analysis of the National Hospital Ambulatory Medical Care Survey (NHAMCS, 2005-2018) characterizing ED visits in patients ≥35 years of age with Asthma Only, COPD Only or ACO. We performed univariable and multivariable analyses adjusting for demographics to assess relevant ED outcome variables.

RESULTS

From 2005 to 2018, there were an estimated 8.15, 17.78 and 0.56 million ED visits for Asthma Only, COPD Only and ACO, respectively. ACO patients were younger than COPD Only patients (mean age 50.18 versus 61.79; p < 0.001). ACO patients differed in terms of sex, race and ethnicity from patients with either disease alone. When triaged, Asthma Only (adjusted odds ratio (aOR) = 11.45; 95% confidence interval (CI), 1.20-109.38) patients were more likely to require immediate care than ACO patients. Although admission rates were comparable between groups, ACO patients had a decreased mean length of ED visit compared to both Asthma Only (p < 0.001) and COPD Only (p < 0.05) patients. COPD Only patients were less likely than ACO patients to be seen in the ED in the last 72 h (aOR = 0.22; 95% CI, 0.056-0.89), receive nebulizer therapy (aOR = 0.55; 95% CI, 0.31-0.97), bronchodilators (aOR = 0.24; 95% CI, 0.12-0.48) and systemic corticosteroids (aOR = 0.18; 95% CI, 0.091-0.35). Asthma Only patients were less likely than ACO patients to undergo any imaging (aOR = 0.55; 95% CI, 0.31-0.96) and receive antibiotics (aOR = 0.46; 95% CI, 0.23-0.93).

CONCLUSIONS

ACO patients appear to differ demographically from patients with either disease alone in the ED. After adjustment for these demographic differences, ACO patients appear to differ with respect to several ED variables, notably respiratory therapies; however, clinical outcomes including admission and mortality rates appear to be comparable between groups.

Biologic Treatments for Asthma and Chronic Obstructive Pulmonary Disorder

The global COVID-19 pandemic has brought respiratory disease to the forefront of public health, but asthma prevalence has been rising globally for decades. Asthma is mediated by errant immune activation and airway remodeling, but the influences of environment, nutrition, and comorbidities (e.g., asthma-chronic obstructive pulmonary disorder-overlap [ACO]) are still poorly understood. Even as a new generation of biologic-based treatments offer better airway control and reductions in mortality, a lack of prophylactic treatments and mechanistic understanding complicates efforts to prevent pathogenesis. This review will explicate and synthesize current knowledge on the effect of ACO and biologics (omalizumab, mepolizumab, reslizumab, benralizumab, and dupilumab) on pathogenesis, treatment, and prognosis.

Asthma and Chronic Obstructive Pulmonary Disease Overlap According to the Japanese Respiratory Society Diagnostic Criteria: The Prospective, Observational ACO Japan Cohort Study

INTRODUCTION

Patients with asthma-chronic obstructive pulmonary disease (COPD) overlap (ACO) present with chronic respiratory symptoms with features of both asthma and COPD. New ACO diagnostic criteria (2018) were suggested by the Japanese Respiratory Society (JRS). This prospective, multicenter, observational cohort study was conducted to investigate the proportion of patients who meet the JRS ACO diagnostic criteria among COPD patients in clinical practice.

METHODS

This 2-year ongoing study enrolled consecutive outpatients aged ≥ 40 years with COPD who visited one of 27 Japanese centers at which the medical examinations/tests required for ACO diagnosis were routinely conducted. At registration, the proportion of ACO or non-ACO patients was determined using the JRS diagnostic criteria, and the characteristics of the two groups were compared using analysis of variance and chi-square test.

RESULTS

Of 708 COPD patients analyzed at registration, 396 (55.9%) had the data necessary for ACO diagnosis to be conducted, and 312 (44.1%) were lacking these data. Of the 396 patients who had the data necessary for ACO diagnosis, 101 (25.5%) met the diagnostic criteria for ACO, and 295 (74.5%) did not (non-ACO patients). ACO patients were younger, had a greater rate of asthma based on a physician's diagnosis, and used more medications, including inhaled corticosteroids (p < 0.05), compared with non-ACO patients.

CONCLUSIONS

We have determined the proportion of patients with the data necessary to diagnose ACO using the JRS criteria, and the proportion of these who met the ACO criteria among the COPD population at the time of registration. Patients, including those lacking necessary examination/test data at registration, will continue to undergo follow-up to explore changes in their testing and ACO diagnostic status over time. Analyses of study data over 2 years will provide relevant information on the ACO symptoms, clinical course, and real-world treatment patterns.

TRIAL REGISTRATION

ClinicalTrials.gov identifier, NCT03577795.

A Patient Charter for Chronic Obstructive Pulmonary Disease

Chronic obstructive pulmonary disease (COPD) has a profound impact on people living with the disease and has a high global economic and social burden. Often, people with COPD are undiagnosed, while those diagnosed are undertreated and undereducated on different aspects of COPD care. Although there are many published evidence-based treatment guidelines from different expert groups and societies, they are frequently not adhered to, which results in significant gaps in care. In particular, 'flare-ups' (known as exacerbations of COPD), which accelerate disease progression, are often under-reported, despite guidelines recommending an escalation of maintenance treatment to prevent subsequent flare-ups. Management of COPD should be proactive to prevent worsening of symptoms and to reduce the risk of future flare-ups and premature death, rather than a secondary reaction to a worsening health status. Key to this is patient access to accurate diagnosis, effective treatment and specialist care, which can vary widely due to socioeconomic differences, geographical locations and poor guideline implementation. In addition, the stigma associated with COPD can act as a barrier, which can result in people being reluctant to access treatment or clinicians being nihilistic. As global patient advocates, we have co-developed this patient charter to set a standard of care that people living with COPD should expect, raising awareness and understanding of the causes and consequences of COPD as well as the potential to improve patient care. Patients with COPD should be empowered to live the highest quality of life possible with the least number of flare-ups. We set out six principles in line with current COPD guideline recommendations, that should be implemented by governments, healthcare providers, policymakers, lung health industry partners and patients/caregivers to drive meaningful change in COPD care.

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.

Asthma-COPD overlap in World Trade Center Health Registry enrollees, 2015-2016

INTRODUCTION

Asthma-chronic obstructive pulmonary disease (COPD) overlap (ACO) is a newly redefined form of chronic airway disease and has not been well studied among 9/11-exposed populations with increased prevalence of asthma. We assessed the prevalence and risk factors associated with ACO in an exposure cohort of World Trade Center Health Registry (WTCHR) enrollees.

METHODS

This is a longitudinal study, including enrollees with complete data on 9/11/01 exposure at enrollment (2003-2004, Wave 1), asthma and COPD diagnoses and at least 25 years of age at the time of the 2015-2016 (Wave 4) WTCHR survey. Probable ACO was defined as self-reported post-9/11 physician-diagnosed asthma and either emphysema, chronic bronchitis, or COPD. We evaluated whether probable ACO was associated with World Trade Center (WTC)-related exposures, using multivariable logistic regression.

RESULTS

Of 36,864 Wave 4 participants, 29,911 were eligible for this analysis, and 1,495 (5.0%) had self-reported post-9/11 probable ACO. After adjusting for demographics and smoking status, we found 38% increased odds of having ACO in enrollees with exposure to the dust cloud, and up to 3.39 times the odds in those with ≥3 injuries sustained on 9/11. Among rescue/recovery workers, ever working on the pile, on the pile on 9/11 or 9/12/01, or working on the WTC site for >7 days showed increased odds ratios of having ACO.

CONCLUSION

Probable ACO is associated with WTC exposures. Further study of ACO is needed to understand the development of this and other environmentally or occupationally-related airway diseases, and how to prevent these in disasters like 9/11.

Coexisting COPD Increases Mortality in Patients With Corticosteroid-Dependent Asthma: A Nationwide Population-Based Study

PURPOSE

Chronic corticosteroid (CS) use is a risk factor for long-term mortality in asthmatic patients, and the presence of coexisting chronic obstructive pulmonary disease (COPD) is associated with a severe presentation and poor prognosis. However, the impact of coexisting COPD on long-term mortality in patients with CS-dependent asthma has not been well elucidated. This study aimed to determine the impact of coexisting COPD on long-term mortality in patients with CS-dependent asthma.

METHODS

A retrospective cohort of patients with CS-dependent asthma aged 40 years or older was established using records from the Korean National Health Insurance Service database for 2005 to 2015. We classified the subjects into 2 groups according to the presence of COPD and evaluated the hazard ratio (HR) for all-cause mortality in patients with COPD relative to those without COPD.

RESULTS

Of 8,021 patients with CS-dependent asthma, 3,121 (38.9%) had COPD. All-cause mortality was significantly greater in patients with CS-dependent asthma and COPD than in those without COPD (9,955/100,000 person-years vs. 5,585/100,100 person-years, P < 0.001). The adjusted HRs were 1.29 (95% confidence interval [CI], 1.21-1.38), and the associations were especially significant for chronic lower respiratory diseases (subdistribution HR, 2.30; 95% CI, 2.06-2.57) and lung cancer (subdistribution HR, 1.34; 95% CI, 1.02-1.78).

CONCLUSIONS

In this population-based retrospective cohort study, the presence of physician-recognized COPD was associated with greater all-cause mortality and greater risk of mortality due to chronic lower respiratory diseases and lung cancer in patients with CS-dependent asthma. Early recognition and appropriate management of COPD can improve treatment outcomes in patients with CS-dependent asthma.

Triple Therapy with Budesonide/Glycopyrrolate/Formoterol Fumarate Improves Inspiratory Capacity in Patients with Asthma-Chronic Obstructive Pulmonary Disease Overlap

Purpose

Asthma-chronic obstructive pulmonary disease overlap (ACO), characterized by airway limitation, is an important condition with high incidence and mortality. Although some guidelines recommend triple therapy with inhaled corticosteroids/long-acting muscarinic antagonists/long-acting β2 agonists, this treatment approach is based on the extrapolation of data from studies of asthma or chronic obstructive pulmonary disease (COPD) alone.

Methods

A 12-week, randomized, open-label cross-over pilot study was conducted in 19 patients with ACO to investigate the effect of triple therapy with glycopyrrolate (GLY) 50 µg/day on budesonide/formoterol fumarate (BUD/FORM) 640/18 µg/day. The study period included a 4-week wash-out, 4-week run-in, and 4-week treatment period. Respiratory function tests, fractional exhaled nitric oxide (FeNO), a COPD assessment test (CAT) and an asthma control questionnaire (ACQ) were carried out 0, 4, and 8 weeks after randomization.

Results

A total of 19 patients with stable ACO (19 males and no females) with a mean age of 70.7 ± 7.6 years (± standard deviation, SD; range 55-83 years) participated in this study. All patients were ex-smokers with a smoking history of 63.1 ± 41.1 pack-years (± SD). Mean values for inspiratory capacity (IC), an index of hyperinflation of the lung that causes exertional dyspnea and reduced exercise, were 1.93 L (± 0.47 L) after the run-in, 1.85 L (± 0.51 L) after the BUD/FORM dual therapy period and 2.11 L (± 0.58 L) after the BUD/GLY/FORM triple therapy period. IC values after the BUD/GLY/FORM triple therapy were significantly higher than those after the run-in (p < 0.02). FeNO values, ACQ, and CAT scores were not significantly different among the run-in, wash-out, and triple-therapy periods.

Conclusion

The present pilot study showed that triple therapy with BUD/GLY/FORM results in an improvement in lung function parameters including IC, indicating the potential value of triple therapy as standard treatment for ACO.

Managing the overlap of asthma and chronic obstructive pulmonary disease

Approximately 20% of patients with obstructive lung disease have features of both asthma and chronic obstructive pulmonary disease

These patients have a higher burden of disease and increased exacerbations compared to those with asthma or chronic obstructive pulmonary disease alone

Management should address dominant clinical features in each individual patient, and comorbidities should be considered

There are several interventions that are useful in the management of both asthma and chronic obstructive pulmonary disease

As inhaled corticosteroids are key to the management of asthma, they are recommended in patients with overlapping chronic obstructive pulmonary disease

Asthma-COPD Overlap and Chronic Airflow Obstruction: Definitions, Management, and Unanswered Questions

Asthma-chronic obstructive pulmonary disease (COPD) overlap (ACO) is a common clinical presentation of chronic airways disease in which patients show some features usually associated with asthma, and some usually associated with COPD. There is ongoing debate over whether ACO is a discrete clinical entity, or if it is part of a continuum of airways disease. Furthermore, there is considerable variation among current definitions of ACO, which makes diagnosis potentially challenging for clinicians. Treating ACO may be equally challenging because ACO is an understudied population, and the evidence base for its management comes largely from asthma and COPD studies, the relevance of which deserves careful consideration. In this review, we synthesize the various approaches to ACO diagnosis and evaluate the role of currently available diagnostic tests. We describe the potential benefits of existing asthma and COPD therapies in treating patients with ACO, and the value of a "treatable traits" approach to ACO management. Throughout the review, we highlight some of the pressing, unanswered questions surrounding ACO that are relevant to the clinical community. Ultimately, addressing these questions is necessary if we are to improve clinical outcomes for this complex and heterogeneous patient population.

Global prevalence of asthma-COPD overlap (ACO) in the general population: a systematic review and meta-analysis

Background

Asthma-COPD overlap (ACO) is a term that encompasses patients with features of both asthma and COPD. To date, the global prevalence of ACO in the general population remains unknown. The objective of this study was to estimate the prevalence of ACO in the general population using a systematic review and meta-analysis.

Methods

A systematic search of ISI Web of Knowledge, MEDLINE/PubMed, and Scopus was performed up to May 2019 to identify studies reporting the prevalence of ACO. Reference lists from identified studies and relevant review articles were also searched. Eligibility criteria were studies reporting the prevalence of ACO, performed in general population, and published in English language. Pooled prevalence of ACO with 95% confidence interval (CI) was calculated using random effects Meta-analysis.

Results

A total of 27 studies were included in this meta-analysis. The Cochran Q test and I² statistics revealed substantial heterogeneity among studies. Based on the random-effects model, the pooled prevalence of ACO was 2.0% (95% CI: 1.4–2.6%) in the general population, 26.5% (95% CI: 19.5–33.6%) among patients with asthma, and 29.6% (95% CI: 19.3–39.9%) among patients with COPD. In addition, for included studies, the global prevalence of asthma-only was 6.2% (95% CI: 5.0–7.4%) and COPD-only was 4.9% (95% CI: 4.3–5.5%).

Conclusion

We estimated the global prevalence of ACO based on population-based studies and found that 2.0% of the general population is affected. However, the prevalence of ACO depends on its diagnostic criteria. Therefore, there is a vital need to better define the ACO diagnostic criteria, management and treatment. It is worth noting that the limitations of the present study include lack of studies in some region of the world and small number of studies included in the subgroup analyses.

Effect of triple therapy in patients with asthma-COPD overlap

OBJECTIVE

Asthma-chronic obstructive pulmonary disease (COPD) overlap (ACO) is of increasing interest because ACO patients have significantly worse outcomes, leading to greater social and economic burdens compared with asthma or COPD alone. Some guidelines for ACO recommend triple therapy with inhaled corticosteroids, long-acting β2 agonists, and long-acting muscarinic antagonists. However, this approach is based on extrapolating data from patients with asthma or COPD alone. Therapeutic studies for ACO have not previously been conducted.

MATERIALS AND METHODS

A 12-week, randomized, open-label cross-over pilot study was conducted in 17 ACO patients to evaluate the effect of umeclidinium (UMEC) 62.5 µg once-daily added to fluticasone furoate/vilanterol (FF/VI) 200/25 µg once-daily. A 4-week run-in, a first and a second 4-week treatment period were included. Respiratory function, respiratory impedance, fractional exhaled nitric oxide, COPD assessment test, and asthma control test scores were evaluated 0, 4, and 8 weeks after randomization.

RESULTS

Mean values of post-bronchodilator forced expiratory volume in 1 second as a percentage of the predicted value (%FEV1), after UMEC was added to FF/VI, were significantly higher than after the run-in (p < 0.01). Mean values of resonant frequency during inspiration (Fres), after UMEC was added to FF/VI, were significantly lower than after the run-in (p < 0.01).

CONCLUSION

Adding UMEC to FF/VI provides greater improvement in lung function, indicating that triple therapy is a suitable regular treatment for ACO.

Management of asthma COPD overlap

OBJECTIVE

To review the latest literature on management approaches to patients with asthma chronic obstructive pulmonary disease (COPD) overlap (ACO).

DATA SOURCES

Studies and reports were identified from the databases of PubMed/Medline and ClinicalTrials.gov from the US National Institutes of Health and the Cochrane Register of Controlled Trials.

STUDY SELECTIONS

Studies on the management of asthma, COPD, and ACO were included in this review.

RESULTS

Patients with asthma COPD overlap tend to have greater morbidity than those with asthma or COPD alone, but the information on the best therapeutic approach to this group of patients is still limited. Current treatment recommendations rely on expert opinions, roundtable discussions, and strategy documents, because most clinical studies in asthma and COPD have excluded patients with ACO. Because of the potential risk described in patients with asthma with the use of long-acting 2 agonist monotherapy, initial therapy for patients with ACO is recommended to include a long-acting bronchodilator in conjunction with inhaled corticosteroids. Long-acting muscarinic antagonists are effective in both asthma and COPD and should be considered in ACO as an add-on treatment. If inhaler therapy is not effective, advanced therapies based on phenotyping and identification of treatable traits may be considered.

CONCLUSION

Few studies have evaluated prospectively therapies in the ACO population, and future studies need to determine best strategies for the treatment of these patients, focusing on targeting its different phenotypes and its treatable traits.

Asthma progression and mortality: the role of inhaled corticosteroids

Overall, asthma mortality rates have declined dramatically in the last 30 years, due to improved diagnosis and to better treatment, particularly in the 1990s following the more widespread use of inhaled corticosteroids (ICSs). The impact of ICS on other long-term outcomes, such as lung function decline, is less certain, in part because the factors associated with these outcomes are incompletely understood. The purpose of this review is to evaluate the effect of pharmacological interventions, particularly ICS, on asthma progression and mortality. Furthermore, we review the potential mechanisms of action of pharmacotherapy on asthma progression and mortality, the effects of ICS on long-term changes in lung function, and the role of ICS in various asthma phenotypes.

Overall, there is compelling evidence of the value of ICS in improving asthma control, as measured by improved symptoms, pulmonary function and reduced exacerbations. There is, however, less convincing evidence that ICS prevents the decline in pulmonary function that occurs in some, although not all, patients with asthma. Severe exacerbations are associated with a more rapid decline in pulmonary function, and by reducing the risk of severe exacerbations, it is likely that ICS will, at least partially, prevent this decline. Studies using administrative databases also support an important role for ICS in reducing asthma mortality, but the fact that asthma mortality is, fortunately, an uncommon event makes it highly improbable that this will be demonstrated in prospective trials.

There is compelling evidence of the value of ICS in improving asthma control and indirect evidence that ICS prevents lung function decline by preventing severe exacerbations. Registry-based studies support the role of ICS in reducing asthma mortality.http://bit.ly/2VcNjaz

Association between asthma/chronic obstructive pulmonary disease overlap syndrome and healthcare utilization among the US adult population

Objectives: Asthma/chronic obstructive pulmonary disease (COPD) overlap (ACO) is a recently described phenomenon defined as the coexistence of both asthma and COPD. Both asthma and COPD are known to result in increased emergency department (ED) visits and hospitalizations, but it is unclear how the ACO population utilizes these same healthcare resources. The objective of this study was to compare healthcare utilization in the ACO population versus the general population, the asthma population and the COPD population. Methods: We conducted a pooled cross-sectional statistical analysis using the 2012-2015 National Health Interview Survey (NHIS) data. We focused on adults 18 years of age and older and excluded pregnant women. We employed an adjusted logit regression model, where the primary outcomes were dichotomous indicators on healthcare utilizations including ED visits and hospital stays. A key covariate was a four-category variable: 1) no asthma or COPD; 2) asthma only; 3) COPD only; and 4) ACO. Other covariates included age, sex, race, education level, marital status, household income level, medical insurance status, smoking status, body mass index (BMI) category, region, year and comorbidities (cancer, diabetes, hypertension, coronary heart disease and ulcer). Results: Adults with ACO were 134%, 53% and 21% more likely to have ED visits than the general population, asthma group and COPD group, respectively. For hospital stay, the ACO group was 120% and 86% more likely to be hospitalized than the general population and the asthma group respectively. In addition, adults with ACO were 61% and 130% more likely to have asthma exacerbations and asthma-related ED visits than the asthma group. Conclusions: ACO is a considerable risk factor for healthcare utilization versus the general population, the asthma population and the COPD population. Future focus should be placed on the ACO population to identify ways to reduce their healthcare utilization.

Prevalence and features of asthma-COPD overlap in the United States 2007-2012

BACKGROUND

Perceived to be distinct, asthma and chronic obstructive pulmonary disease (COPD) can co-exist and potentially have a worse prognosis than the separate diseases. Yet, little is known about the exact prevalence and the characteristics of the Asthma-COPD overlap (ACO) in the US population.

AIMS

To determine ACO prevalence in the United States, identify ACO predictors, examine ACO association with asthma and COPD severity, and describe distinctive spirometry and laboratory features of ACO.

METHODS

Data on adult participants to the National Health and Nutrition Examination Surveys conducted from 2007 to 2012 was analyzed. ACO was defined as current asthma and post-bronchodilator forced expiratory volume in 1 second/forced vital capacity (FEV1/FVC) <0.7.

RESULTS

Overall, 7,570 participants representing 98.58 million Americans were included in our study. From 2007 to 2012, the crude and age-standardized ACO prevalence were, respectively, 0.96% (95% CI: 0.65%-1.26%) and 1.05% (0.74%-1.37%). In asthma, ACO predictors included older age, male gender, and smoking. In COPD, ACO predictors were non-Hispanic Black race/ethnicity and obesity. ACO was associated with increased ER visits for asthma (OR = 3.46, 95% CI: 1.48-8.06]) and oxygen therapy in COPD (OR = 11.17, 95% CI: 5.17-24.12]). In spirometry, FEV1 and peak expiratory flow were lower in ACO than in asthma or COPD alone.

CONCLUSION

Age-adjusted prevalence of ACO in the United States was 1.05% in 2007-2012, representing 0.94 (95% CI: 0.62-1.26) million Americans. It is much lower than previously reported. The overlap was associated with higher asthma and COPD severity as well as decreased lung function compared with COPD or asthma alone.

Microbiological features of bronchial asthma and chronic obstructive pulmonary disease during remission

Background: Bronchial asthma and chronic obstructive pulmonary disease are currently the fifth leading cause of death in the world. The combination of bronchial asthma and chronic obstructive pulmonary disease seems to be a unique disease resulting from the interaction of genetic, pathological and functional factors. Aim: Study of clinical and functional parameters, bacterial spectrum in patients with combination of asthma and chronic obstructive pulmonary diseases bronchitis and non-bronchitis types. Methods: Clinical and functional examination of 69 patients with obstructive respiratory diseases, of which 49 patients with asthma combined with chronic obstructive pulmonary disease of bronchitis and non-bronchitis types. The microbiological spectrum of nasal pharynx induced by sputum was studied. Results: The following microorganisms were isolated: Staphylococcus (S. aureus, S. epidermidis), Neisseria subflava, Streptococcus (α-haemolyticus, β-haemolyticus), Streptococcus pneumoniae, Pseudomonas aeruginosa, Escherichia coli, Klebsiella pneumoniae, Branhamella catarrhalis, Enterococcus, Haemophilus influenzae, Candida albicans, Aspergillus spp., Actinomyces spp., Cladosporium, Penicillium, and others. Conclusion: A more pronounced quantitative content and a more diverse microbial landscape leads to a more severe course of the disease asthma combined withchronic obstructive pulmonary disease especially of the bronchitis type.

Mortality in Asthma-Chronic Obstructive Pulmonary Disease Overlap in the United States

OBJECTIVES

Asthma-chronic obstructive pulmonary disease (COPD) overlap (ACO) is recognized increasingly as a distinct clinical entity and is associated with higher comorbidities compared with patients with asthma and COPD alone. Little is known about the leading causes of death related to ACO in the US general population, however. Our aim was to define the causes of mortality among patients with ACO compared with asthma and COPD in the US population.

METHODS

We examined questions using the National Health and Nutrition Examination Survey III database linked to the National Death Index. The data from 4434 participants were stratified into 4 groups, those with asthma, COPD, ACO, and those without any obstructive lung disease. We examined baseline demographics and used multivariate logistic regression to model the impact of demographics, smoking, and self-reported, physician-diagnosed lung disease on mortality generating odds ratios (ORs) and confidence intervals (CIs).

RESULTS

Among 4434 participants, 120 (2.7%), 340 (7.6%), and 126 (2.8%) participants self-reported diagnoses of asthma, COPD, and ACO syndrome, respectively. Patients with COPD were older (69.7 ± 10.9 years) than other groups. Cardiovascular disease, malignancy, and chronic lower respiratory disease were frequent causes of death. The mortality rates for cardiovascular disease and malignancy were not significantly different among respiratory disease categories. Deaths resulting from chronic respiratory disease were higher in the ACO group (OR 4.9, 95% CI 2.5-9.4) and the COPD group (OR 2.9, 95% CI 1.5-5.4) when compared with those without obstructive lung disease (P < 0.0001).

CONCLUSIONS

Although cardiovascular- and malignancy-related deaths are common, a higher proportion of mortality in ACO and COPD is attributed to chronic lung disease.

Asthma COPD overlap: Impact of associated comorbidities

Asthma and chronic obstructive pulmonary disease (COPD) are common chronic pulmonary conditions worldwide which often coexist. Patients with asthma COPD overlap (ACO) may have worse outcomes than those with either disease alone, for example, more respiratory symptoms and frequent exacerbations, and worse lung function. Additionally, there is a growing interest in factors that affect the disease including comorbid conditions. Indeed, recent studies have demonstrated higher rates of comorbid conditions in the ACO population, but the mechanisms behind these observations remain unclear. The objective of this review is to describe current knowledge and clinical implications of the overlapping features of asthma and COPD, and discuss the prevalence and impact of comorbidities, such as osteoporosis, cardiovascular disease, gastroesophageal reflux disease, and depression, in this subgroup of patients.

Clinical Approach to the Therapy of Asthma-COPD Overlap

Over the last few years, there has been a renewed interest in patients with characteristics of both asthma and COPD. Although the precise definition of asthma-COPD overlap (ACO) is still controversial, patients with overlapping features are frequently encountered in clinical practice, and may indeed have worse clinical outcomes and increased health-care utilization than those with asthma or COPD. Therefore, there is a critical need to set a framework for the therapeutic approach of such patients. There are key distinctions in the therapy between asthma and COPD, particularly regarding the initial choice of therapy. However, there is considerable overlap in the use of existing medications for both diseases. Furthermore, novel therapies approved for asthma, such as monoclonal antibodies, may have a role in patients with COPD and ACO. The use of biomarkers, such as peripheral blood eosinophils, exhaled nitric oxide, and serum IgE, may help in selecting appropriate therapies for ACO. In this review, we provide an overview of available treatments for both asthma and COPD and explore their potential role in the treatment of patients with ACO.

COPD phenotypes: differences in survival

Background

The aim of the study was to analyze the characteristics and survival of a group of patients with COPD according to their clinical phenotype.

Patients and methods

The study population was selected from patients undergoing scheduled spirometry between January 1, 2011 and June 30, 2011 at the respiratory function laboratory of a teaching hospital and comprised those with a previous and confirmed diagnosis of COPD and forced expiratory volume in the first second (FEV₁) of <70%. The patients selected were classified into 4 groups: positive bronchodilator response, non-exacerbator, exacerbator with emphysema, and exacerbator with chronic bronchitis. Patients were followed up until April 2017.

Results

We recruited 273 patients, of whom 89% were men. The distribution by phenotype was as follows: non-exacerbator, 47.2%; positive bronchodilator response, 25.8%; exacerbator with chronic bronchitis, 13.8%; and exacerbator with emphysema, 13.0%. A total of 90 patients died during follow-up (32.9%). Taking patients with a positive bronchodilator response as the reference category, the risk factors that were independently associated with death were older age (HR, 1.06; 95% CI, 1.03-1.09), lower FEV₁ (HR, 0.98; 95% CI, 0.96-0.99), and exacerbator with chronic bronchitis phenotype (HR, 3.28; 95% CI, 1.53-7.03).

Conclusion

Classification of COPD patients by phenotype makes it possible to identify subgroups with different prognoses. Thus, mortality was greater in exacerbators with chronic bronchitis and lower in those with a positive bronchodilator response.

Higher mortality of adults with asthma: A 15-year follow-up of a population-based cohort

BACKGROUND

Higher all-cause mortality in asthmatics has been shown previously. Polysensitization is associated with higher morbidity among asthmatic children, and allergic rhinitis and/or allergic conjunctivitis (AR/AC) are associated with higher morbidity in adult asthmatics. Little is known about the effect of AR/AC and other factors on mortality among adult asthmatics. The aim was to study mortality and its risk factors in adults with and without asthma.

METHODS

We randomly selected 1648 asthmatics with age over 30 years from national registers and matched the asthma sample with one or two controls. Baseline information was obtained by a questionnaire in 1997, and the study population was linked with the death certificate information of Statistics Finland from 1997 to 2013. Overall and cause-specific survival between the groups was compared in several adjusted models.

RESULTS

During a mean follow-up period of 15.6 years, 221 deaths among 1052 asthma patients and 335 deaths among 1889 nonasthmatics were observed. Cardiovascular diseases were the main cause of death in both groups. Asthma was associated with increased all-cause mortality (adjusted HR 1.25; 95% CI 1.05-1.49, P = .011) as well as mortality from chronic obstructive pulmonary disease (HR 12.0, 4.18-34.2, P < .001) and malignant neoplasms of respiratory organs (HR 2.33, 1.25-4.42, P = .008). Among asthmatics, smoking was associated with increased all-cause mortality, and self-reported AR/AC was associated with decreased mortality. Among nonasthmatics, smoking, and obesity were associated with increased all-cause mortality, whereas female gender showed an association with a decreased risk.

CONCLUSIONS

Increased mortality among adult asthmatics was largely explained by the development of COPD, malignant respiratory tract neoplasms, and cardiovascular diseases. Smoking cessation is important for reduction in total mortality in both asthmatic and nonasthmatic adults. AR/AC was associated with decreased mortality only in asthmatics. Thus, studies in other populations of larger size are needed to explore further the nature of this association.

Asthma and COPD overlap (ACO) is related to a high burden of sleep disturbance and respiratory symptoms: Results from the RHINE and Swedish GA2LEN surveys

Background

The term Asthma and COPD Overlap (ACO) describes a condition where asthma and COPD overlap. We aimed to investigate associations between ACO and insomnia and respiratory symptoms, and to investigate the prevalence of ACO and the characteristics of subjects with ACO in two Northern European population studies.

Methods

The study comprised 25 429 subjects aged ≥ 40 years who participated in one of two Northern European general population surveys. Both surveys included questions on asthma, COPD, respiratory and sleep-related symptoms, including difficulty initiating sleep, difficulty maintaining sleep, early-morning awakening, and excessive daytime sleepiness. ACO was defined as having both self-reported asthma and COPD.

Results

The prevalence of ACO was 1.0%. The group with ACO had a higher prevalence of both insomnia and respiratory symptoms than subjects with only asthma or COPD. Having ACO was independently associated with a 2–3 times higher probability of having sleep-related symptoms as compared with the group without asthma or COPD, after adjustment for age, sex, BMI, smoking history and educational level (adjusted odds ratio 2.14–3.36, 95% CI).

Conclusion

Subjects with ACO have a high prevalence of insomnia and respiratory symptoms. To our knowledge, this is the first study to assess the association between sleep-related symptoms and ACO.

Epidemiology of asthma-chronic obstructive pulmonary disease overlap (ACO)

The term "asthma-COPD overlap" (ACO) has been applied to the condition in which a person has persistent airflow limitation with clinical features of both asthma and COPD. The certain definition and diagnostic criteria for ACO have not yet been established, and ACO prevalence has varied widely in studies: from 0.9% to 11.1% in the general population, from 11.1% to 61.0% in asthma patients, and from 4.2% to 66.0% in COPD patients. Furthermore, the frequency of exacerbations and prognosis in ACO patients have not been clearly demonstrated. Although ACO consists with several subgroups of patients with distinct clinical and pathophysiological features, it would be important to propose a standardized definition of and/or diagnostic criteria for ACO based on biomarkers and objective measures, even if it is tentative. It may lead cohort studies with large population or clinical trials around the world.

Definition and diagnosis of asthma-COPD overlap (ACO)

It is now widely recognized that asthma and COPD can coexist as asthma-COPD overlap (ACO), but the preliminary attempts at providing universal guidelines for the diagnosis of ACO still need to be improved. We believe that a case can be made for devising guidelines for the diagnosis of this increasingly common disease that are specific to Japan. In this paper, we present our consensus-based description of ACO which we believe is realistic for use in our country. In addition, we cite the scientific evidence for our own "objective" features used to develop the criteria for COPD and asthma diagnosis. We acknowledge that they will need to be validated and updated over time, but hope the results will encourage further research on the characteristics and treatment of this commonly encountered clinical problem.

Redefining the overlap of asthma and COPD

The term asthma-COPD overlap (ACO) has been suggested for people with chronic airflow obstruction that has features characteristic of both asthma and chronic obstructive pulmonary disease (COPD).¹ People with clinical features of asthma and COPD tend to have worse outcomes than those with either asthma or COPD alone, yet their clinical management has remained unclear. UK guidelines currently do not specifically address this issue,^2,3 but the Global Initiative for Asthma (GINA) and the Global Initiative for Chronic Obstructive Lung Disease (GOLD) have published a consensus-based report on the diagnosis and treatment of people with asthma, COPD and ACO.¹ Although 'asthma-COPD overlap syndrome' (ACOS) was briefly used, some thought that it gave the unhelpful impression that it referred to a single disease entity. Here, we consider some of the challenges in managing this heterogeneous group of patients.

Burden of asthma and COPD overlap (ACO) in Taiwan: a nationwide population-based study

BACKGROUND

Patients with symptoms of both asthma and chronic obstructive pulmonary disease (COPD) may be classified with the term asthma-COPD overlap (ACO). ACO is of considerable interest as it is currently poorly characterised and has been associated with worse health outcomes and higher healthcare costs compared with COPD or asthma alone. Patients with ACO in Asia remain poorly described, and there is limited information regarding their resource utilisation compared with patients with asthma or COPD only. This study investigated the characteristics, disease burden and medical resource utilisation of patients with ACO in Taiwan.

METHODS

This was a retrospective cohort study of patients identified from National Health Insurance (NHI) claims data in Taiwan in 2009-2011. Patients were classified into incident ACO, COPD or asthma cohorts according to International Classification of Disease, ninth revision, clinical modification codes in claims. Eligible patients were ≥40 years of age with 12 months' continuous enrolment in the NHI programme pre- and post-index date (date of the first relevant medical claim).

RESULTS

Patients with ACO (N = 22,328) and COPD (N = 69,648) were older and more likely to be male than those with asthma (N = 50,293). Patients with ACO had more comorbidities and exacerbations, with higher medication use: short-acting β2-agonist prescriptions ranged from 30.4% of patients (asthma cohort) to 43.6% (ACO cohort), and inhaled corticosteroid/long-acting β2-agonist combination prescriptions ranged from 11.1% (COPD cohort) to 35.0% (ACO cohort) in the 12 months following index. Patients with ACO generally had the highest medication costs of any cohort (long-acting muscarinic antagonist costs ranged from $227/patient [asthma cohort] to $349/patient [ACO cohort]); they also experienced more respiratory-related hospital visits than patients with asthma or COPD (mean outpatient/inpatient visits per patient post-index: 9.1/1.9 [ACO cohort] vs 5.7/1.4 [asthma cohort] and 6.4/1.7 [COPD cohort]).

CONCLUSIONS

Patients with ACO in Taiwan experience a greater disease burden with greater healthcare resource utilisation, and higher costs, than patients with asthma or COPD alone.

Perceptions of Severe Asthma and Asthma-COPD Overlap Syndrome Among Specialists: A Questionnaire Survey

Purpose

Severe asthma and asthma-chronic obstructive pulmonary disease (COPD) overlap syndrome (ACOS) are difficult to control and are often associated with poor clinical outcomes. However, much is not understood regarding the diagnosis and treatment of severe asthma and ACOS. To evaluate the current perceptions of severe asthma and COPD among asthma and COPD specialists, we designed an e-mail and internet-based questionnaire survey.

Methods

Subjects were selected based on clinical specialty from among the members of the Korean Academy of Asthma, Allergy and Clinical Immunology and the Korean Academy of Tuberculosis and Respiratory Diseases. Of 432 subjects who received an e-mail invitation to the survey, 95 subjects, including 58 allergists and 37 pulmonologists, responded and submitted their answers online.

Results

The specialists estimated that the percentage of severe cases among total asthma patients in their practice was 13.9%±11.0%. Asthma aggravation by stepping down treatment was the most common subtype, followed by frequent exacerbation, uncontrolled asthma despite higher treatment steps, and serious exacerbation. ACOS was estimated to account for 20.7% of asthma, 38.0% of severe asthma, and 30.1% of COPD cases. A history of smoking, persistently low forced expiratory volume in 1 second (FEV1), and low FEV1 variation were most frequently classified as the major criteria for the diagnosis of ACOS among asthma patients. Among COPD patients, the highly selected major criteria for ACOS were high FEV1 variation, positive bronchodilator response, a personal history of allergies and positive airway hyperresponsiveness. Allergists and pulmonologists showed different assessments and opinions on asthma phenotyping, percentage, and diagnostic criteria for ACOS.

Conclusions

Specialists had diverse perceptions and clinical practices regarding severe asthma and ACOS patients. This heterogeneity must be considered in future studies and strategy development for severe asthma and ACOS.

The Prevalence and Symptom Profile of Asthma-COPD Overlap: The HUNT Study

The concept of asthma and COPD as separate conditions has been questioned, and the term asthma-COPD overlap syndrome has been introduced. We assessed the prevalence, symptoms, and lifestyle factors of asthma-COPD overlap (ACO) in a large Norwegian population-based study. From 2006 to 2008, a total of 50,777 residents of Nord-Trøndelag participated in the Nord-Trøndelag Health Study, Norway. They completed questionnaires regarding respiratory symptoms, disease status, and medication use. We estimated the prevalence and 95% confidence intervals of ACO. Additionally, spirometry was used to estimate the prevalence of ACO in a subgroup. The prevalence of self-reported ACO was 1.9%, and in age groups <40, 40-60 and ≥60 years it was 0.7%, 1.4%, and 3.2%, respectively. Among those reporting COPD, the proportion of ACO was 0.56. In the spirometry subgroup when ACO was defined as doctor diagnosed asthma ever and FEV₁/FVC < 0.70, the prevalence of ACO was 2.0%. All respiratory symptoms, separately or in combination, as well as medication use were reported most frequently in those with ACO compared to the other groups. Strikingly, we observed a two-fold higher proportion of allergic rhinitis in ACO compared to COPD only. In this Norwegian population, the prevalence of self-reported ACO was 1.9%, and the corresponding proportion of ACO among those with COPD was 0.56. Participants with ACO generally had the highest proportions of respiratory symptoms compared to asthma or COPD.

Clinical characteristics of patients with chronic obstructive pulmonary disease overlapped with bronchial asthma

BACKGROUND

The clinical characteristics of patients with chronic obstructive pulmonary disease overlapped with bronchial asthma (COPD-BA) have not been discussed thoroughly.

OBJECTIVE

To reveal the clinical features of patients with COPD-BA, to evaluate the risk factors of COPD-BA, and to provide suggestions for COPD individualized therapy.

METHODS

A retrospective observational study was performed. A total of 182 patients with COPD (90 with COPD-BA and 92 with pure COPD) were recruited in the study. Information on the following items was collected: demographics, clinical manifestations, complications, laboratory findings, other histories, and inpatient treatments during exacerbation.

RESULTS

A total of 182 patients were diagnosed with COPD, with 90 (49.45%) being classified as having COPD-BA. Patients with COPD-BA were more likely to be female (P = .004) and experienced more severe respiratory exacerbations (P = .04) despite being younger (P = .008). Those patients at onset of recurrent cough and sputum production were younger (P = .001). Significantly, a positive asthmatic family history (P = .03) was observed. Patients with COPD-BA usually had higher level of total serum IgE (although no differences were observed), had higher positive rates of the serum specific IgE (P = .004), and were more like to have an allergic history (P = .003). Allergic factor was the risk factor of COPD-BA (odds ratio, 4.477). During hospitalization, patients with COPD-BA tended to be treated with systemic corticosteroids (P = .008).

CONCLUSION

Patients with COPD-BA were characterized by persistent airflow limitation with unique clinical features. Allergic factor was associated with the presence of asthmatic characteristics in patients with COPD. When hospitalized for exacerbation, the individualized therapy for COPD-BA might include the use of corticosteroids systemically.