Medical utilization and cost in patients with overlap syndrome of chronic obstructive pulmonary disease and asthma

COPD overlap conditions: Clinical and therapeutic implications

Chronic Obstructive Pulmonary Disease (COPD) is a complex pulmonary condition characterized by chronic airflow limitation. Within the spectrum of COPD, distinct overlap conditions exist, including Asthma-COPD Overlap (ACO), COPD-Obstructive Sleep Apnea (COPD-OSA), Combined Pulmonary Fibrosis and Emphysema (CPFE), and Bronchiectasis-COPD Overlap (BCO). This review provides a comprehensive overview of the clinical and therapeutic implications of these conditions, highlighting the differences in complications compared with COPD alone in addition to the diagnostic challenges of identifying these conditions. Therapeutically tailored approaches are necessary for COPD overlap conditions considering the unique complications that may arise. Optimal pharmacological management, disease-specific interventions, and comprehensive patient-centered care are crucial components of treatment strategies. This review provides insights for healthcare professionals by enhancing their understanding and management of these conditions. This emphasizes the importance of accurate diagnosis and individualized treatment plans, considering the specific complications associated with each COPD overlap condition.

Application research on asthma-COPD overlap using low-dose CT scan and quantitative analysis

PURPOSE

The aim of this study was to assess the proximal airway remodeling, emphysema, and air trapping of asthma-COPD Overlap.

MATERIALS AND METHODS

20 ACO patients, 55 mild to moderate COPD patients and 38 non-severe asthma patients were participated in low-dose dual phase CT scanning and pulmonary function test, comparative analysis was performed to identify differences in CT measurements among three groups.

RESULTS

(Ⅰ) The average age and smoking index of ACO and mild to moderate COPD were both higher than non-severe asthma. ACO and mild to moderate COPD group had a higher proportion of males than non-severe asthma. (Ⅱ) In terms of pulmonary function test, FEV1 (%Pred), FEV1/FVC%, MEF25% (%Pred), MEF 50% (%Pred), MMEF (%Pred), and PEF (%Pred) in ACO were significantly reduced than those in non-severe asthma. (Ⅲ) On proximal airway parameters, ACO exhibited higher WA% and Pi10 compared to mild to moderate COPD. However, there was no statistically significant difference in WA% and Pi10 between ACO and non-severe asthma. (Ⅳ) On CT lung function, the emphysema index VI-910ex of ACO was significantly higher than non-severe asthma.Additionally, ACO demonstrated higher MLDex and VI-856ex compared to non-severe asthma.

CONCLUSIONS

Compared with non-severe asthma, ACO is more common in male patients with older age and a longer history of smoking, which had more severe airflow obstruction and airway dysfunction than non-severe asthma.ACO showed more obvious proximal airway remodeling than mild to moderate COPD, and was more similar to non-severe asthma.The extent of emphysema and air trapping in ACO were more pronounced compared to non-severe asthma.

Sex-Specific Genetic Determinants of Asthma-COPD Phenotype and COPD in Middle-Aged and Older Canadian Adults: An Analysis of CLSA Data

The etiology of sex differences in the risk of asthma-COPD phenotype and COPD is still not completely understood. Genetic and environmental risk factors are commonly believed to play an important role. This study aims to identify sex-specific genetic markers associated with asthma-COPD phenotype and COPD using the Canadian Longitudinal Study on Aging (CLSA) Baseline Comprehensive and Genomic data. There were a total of 1,415 COPD cases. Out of them, 504 asthma-COPD phenotype cases were identified. 20,524 participants without a diagnosis of asthma and COPD served as controls. We performed genome-wide SNP-by-sex interaction analysis. SNPs with an interaction p-value < 10^-5 were included in a sex-stratified multivariable logistic regression for asthma-COPD phenotype and COPD outcomes. 18 and 28 SNPs had a significant interaction term p-value < 10^-5 with sex in the regression analyses of asthma-COPD phenotype and COPD outcomes, respectively. Sex-stratified multivariable analysis of asthma-COPD phenotype showed that 7 SNPs in/near SMYD3, FHIT, ZNF608, RIMBP2, ZNF133, BPIFB1, and S100B loci were significant in males. Sex-stratified multivariable analysis of COPD showed that 8 SNPs in/near MAGI1, COX18, OSTC, ELOVL5, C7orf72 FGF14, and NKAIN4 were significant in males, and 4 SNPs in/near genes CAMTA1, SATB2, PDE10A, and LINC00908 were significant in females. An SNP in the ZPBP gene was associated with COPD in both males and females. Identification of sex-specific loci associated with asthma-COPD phenotype and COPD may offer valuable evidence toward a better understanding of the sex-specific differences in the pathophysiology of the diseases.

Development of a daily predictive model for the exacerbation of chronic obstructive pulmonary disease

Acute exacerbation (AE) of chronic obstructive pulmonary disease (COPD) compromises health status; it increases disease progression and the risk of future exacerbations. We aimed to develop a model to predict COPD exacerbation. We merged the Korean COPD subgroup study (KOCOSS) dataset with nationwide medical claims data, information regarding weather, air pollution, and epidemic respiratory virus data. The Korean National Health and Nutrition Examination Survey (KNHANES) dataset was used for validation. Several machine learning methods were employed to increase the predictive power. The development dataset consisted of 590 COPD patients enrolled in the KOCOSS cohort; these were randomly divided into training and internal validation subsets on the basis of the individual claims data. We selected demographic and spirometry data, medications for COPD and hospital visit for AE, air pollution data and meteorological data, and influenza virus data as contributing factors for the final model. Six machine learning and logistic regression tools were used to evaluate the performance of the model. A light gradient boosted machine (LGBM) afforded the best predictive power with an area under the curve (AUC) of 0.935 and an F1 score of 0.653. Similar favorable predictive performance was observed for the 2151 individuals in the external validation dataset. Daily prediction of the COPD exacerbation risk may help patients to rapidly assess their risk of exacerbation and will guide them to take appropriate intervention in advance. This might lead to reduction of the personal and socioeconomic burdens associated with exacerbation.

GEMA 5.3. Spanish Guideline on the Management of Asthma

The Spanish Guideline on the Management of Asthma, better known by its acronym in Spanish GEMA, has been available for more than 20 years. Twenty-one scientific societies or related groups both from Spain and internationally have participated in the preparation and development of the updated edition of GEMA, which in fact has been currently positioned as the reference guide on asthma in the Spanish language worldwide. Its objective is to prevent and improve the clinical situation of people with asthma by increasing the knowledge of healthcare professionals involved in their care. Its purpose is to convert scientific evidence into simple and easy-to-follow practical recommendations. Therefore, it is not a monograph that brings together all the scientific knowledge about the disease, but rather a brief document with the essentials, designed to be applied quickly in routine clinical practice. The guidelines are necessarily multidisciplinary, developed to be useful and an indispensable tool for physicians of different specialties, as well as nurses and pharmacists. Probably the most outstanding aspects of the guide are the recommendations to: establish the diagnosis of asthma using a sequential algorithm based on objective diagnostic tests; the follow-up of patients, preferably based on the strategy of achieving and maintaining control of the disease; treatment according to the level of severity of asthma, using six steps from least to greatest need of pharmaceutical drugs, and the treatment algorithm for the indication of biologics in patients with severe uncontrolled asthma based on phenotypes. And now, in addition to that, there is a novelty for easy use and follow-up through a computer application based on the chatbot-type conversational artificial intelligence (ia-GEMA).

Increasing the accuracy of the asthma diagnosis using an operational definition for asthma and a machine learning method

INTRODUCTION

Analysis of the National Health Insurance data has been actively carried out for the purpose of academic research and establishing scientific evidences for health care service policy in asthma. However, there has been a limitation for the accuracy of the data extracted through conventional operational definition. In this study, we verified the accuracy of conventional operational definition of asthma, by applying it to a real hospital setting. And by using a machine learning technique, we established an appropriate operational definition that predicts asthma more accurately.

METHODS

We extracted asthma patients using the conventional operational definition of asthma at Seoul St. Mary's hospital and St. Paul's hospital at the Catholic University of Korea between January 2017 and January 2018. Among these extracted patients of asthma, 10% of patients were randomly sampled. We verified the accuracy of the conventional operational definition for asthma by matching actual diagnosis through medical chart review. And then we operated machine learning approaches to predict asthma more accurately.

RESULTS

A total of 4,235 patients with asthma were identified using a conventional asthma definition during the study period. Of these, 353 patients were collected. The patients of asthma were 56% of study population, 44% of patients were not asthma. The use of machine learning techniques improved the overall accuracy. The XGBoost prediction model for asthma diagnosis showed an accuracy of 87.1%, an AUC of 93.0%, sensitivity of 82.5%, and specificity of 97.9%. Major explanatory variable were ICS/LABA,LAMA and LTRA for proper diagnosis of asthma.

CONCLUSIONS

The conventional operational definition of asthma has limitation to extract true asthma patients in real world. Therefore, it is necessary to establish an accurate standardized operational definition of asthma. In this study, machine learning approach could be a good option for building a relevant operational definition in research using claims data.

COPD Patients with Asthma Features in Vietnam: Prevalence and Suitability for Personalized Medicine

COPD patients with asthma features usually benefit from inhaled corticosteroids (ICS)-containing regimens, but their burden and diagnostic criteria remain to be established. The aims of this study were to estimate the proportion of patients with asthma features among patients with physician-diagnosed COPD and to investigate differences in clinical characteristics and current medications between COPD patients with asthma features and patients with COPD alone. A cross-sectional study was conducted at two respiratory out-patient clinics at the University Medical Center in Ho Chi Minh City and Bach Mai Hospital in Ha Noi, Vietnam. COPD patients with asthma features were identified by attending physicians following the approach recommended by the GINA/GOLD joint committee. Of the 332 patients screened, 300 were enrolled in the study. The proportion of COPD patients with asthma features was 27.3% (95% confidence interval (95% CI) 22.6-32.6%). COPD patients with asthma features were younger, with higher FEV₁ values, a greater proportion of positive bronchodilator reversibility tests, higher blood eosinophil count, and were more often treated with ICS/LABA (ICS/long-acting bronchodilator beta-2 agonist) than patients with COPD alone. The prevalence of COPD patients with asthma features is particularly high in Vietnam thus requiring appropriate action plans in clinical practice.

The prevalence of multiple chronic conditions and medical burden in asthma patients

BACKGROUND

The prevalence of multiple chronic conditions (MCC), defined as several coexisting chronic conditions, has increased with the aging of society. MCC is associated with poor outcomes, but most comorbid diseases in asthma patients have been evaluated as asthma-associated diseases. We investigated the morbidity of coexisting chronic diseases in asthma patients and their medical burdens.

METHODS

We analyzed data from the National Health Insurance Service-National Sample Cohort for 2002-2013. We defined MCC with asthma as a group of one or more chronic diseases in addition to asthma. We analyzed 20 chronic conditions, including asthma. Age was categorized into groups 1-5 (< 10, 10-29, 30-44, 45-64, and ≥ 65 years, respectively). The frequency of medical system use and associated costs were analyzed to determine the asthma-related medical burden in patients with MCC.

RESULTS

The prevalence of asthma was 13.01%, and the prevalence of MCC in asthmatic patients was 36.55%. The prevalence of MCC with asthma was higher in females than males and increased with age. The significant comorbidities were hypertension, dyslipidemia, arthritis, and diabetes. Dyslipidemia, arthritis, depression, and osteoporosis were more common in females than males. Hypertension, diabetes, COPD, coronary artery disease, cancer, and hepatitis were more prevalent in males than females. According to age, the most prevalent chronic condition in groups 1 and 2 was depression, dyslipidemia in group 3, and hypertension in groups 4 and 5. Older age, low income, and severe disability were independent risk factors for MCC in patients with asthma. The frequency of asthma-related medical system use and asthma-associated costs increased with increasing numbers of coexisting chronic diseases.

CONCLUSION

Comorbid chronic diseases in asthma patients differed according to age and sex. The asthma-related-medical burdens were highest in patients with five or more chronic conditions and groups 1 and 5.

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.

Increased hospitalizations and economic burden in COPD with bronchiectasis: a nationwide representative study

With the increasing use of computed tomography, bronchiectasis has become a common finding in patients with chronic obstructive pulmonary disease (COPD). However, the clinical aspects and medical utilization of COPD with bronchiectasis (BE) remain unclear. We aimed to investigate the BE effect on prognosis and medical utilization in patients with COPD. Among 263,747 COPD patients, we excluded patients lacking chest X-ray, CT, or pulmonary function test codes and classified 2583 GOLD-C/D patients matched according to age, sex, and medical aid as having COPD-BE (447 [17.3%]) and COPD without BE (2136 [82.7%]). Patients with COPD-BE showed a higher rate of acute exacerbation requiring antibiotics than those without BE. Moreover, multivariable analysis showed that BE co-existence was a crucial factor for moderate-to-severe exacerbation (incidence rate ratio [IRR] 1.071; 95% CI 1.012-1.134; p = 0.019). Patients with COPD-BE had a significantly higher rate of exacerbations requiring antibiotics, as well as treatment cost and duration (meant as number of days using hospitalization plus outpatient appointment), than those with COPD without BE (52.64 ± 65.29 vs. 40.19 ± 50.02 days, p < 0.001; 5984.08 ± 8316.96 vs. 4453.40 ± 7291.03 USD, p < 0.001). Compared with patients with COPD without BE, patients with COPD-BE experienced more exacerbations requiring antibiotics, more hospitalizations, and a higher medical cost.

Short-Term Air Pollution Exposure and Risk of Acute Exacerbation of Chronic Obstructive Pulmonary Disease in Korea: A National Time-Stratified Case-Crossover Study

We investigated the association between short-term exposure to air pollution and the risk of acute exacerbation of chronic obstructive pulmonary disease (AE-COPD) in seven metropolitan cities in Korea. We used national health insurance claims data to identify AE-COPD cases in 2015. We estimated short-term exposure to particulate matter (PM) with a diameter of ≤2.5 μm (PM_2.5), PM with diameters of ≤10 μm (PM₁₀), sulfur dioxide (SO₂), nitrogen dioxide (NO₂), carbon monoxide (CO), and ozone (O₃) obtained from the Ministry of Environment. We conducted a time-stratified, case-crossover study to evaluate the effect of short-term exposure to air pollution on hospital visits for AE-COPD, using a conditional logistic regression model. The risk of hospital visits for AE-COPD was significantly associated with interquartile range increases in PM₁₀ in a cumulative lag model (lag 0–2, 0.35%, 95% confidence interval (CI) 0.06–0.65%; lag 0–3, 0.39%, 95% CI 0.01–0.77%). The associations were higher among patients who were men, aged 40–64 years, with low household income, and with a history of asthma. However, other air pollutants were not significantly associated with the risk of hospital visits for AE-COPD. Short-term exposure to air pollution, especially PM₁₀, increases the risk of hospital visits for AE-COPD.

Current Status of Studies Investigating Asthma-Chronic Obstructive Pulmonary Disease Overlap in Korea: A Review

There is a considerable number of individuals who exhibit features of both asthma and chronic obstructive pulmonary disease (COPD), defined as asthma-COPD overlap (ACO). Many studies have reported that these patients have a greater burden of symptoms, including cough and dyspnea, and experience more exacerbations and hospitalizations than those with non-ACO COPD or asthma. Although diagnostic criteria for ACO have not yet been clearly established, their clinical significance remains to be determined. As interest in ACO grows, related studies have been conducted in South Korea as well. The present review summarizes ACO-related studies in South Korea to better understand Korean ACO patients and guide further research. Several cohort studies of asthma and COPD and population-based studies for ACO were reviewed and the key results from demographics, clinical features, lung function, biomarkers, treatment, and prognosis were summarized.

Pathogenesis, clinical features of asthma COPD overlap (ACO), and therapeutic modalities

Both asthma and COPD are heterogeneous diseases identified by characteristic symptoms and functional abnormalities, with airway obstruction common in both diseases. Asthma COPD overlap (ACO) does not define a single disease but is a descriptive term for clinical use that includes several overlapping clinical phenotypes of chronic airways disease with different underlying mechanisms. This literature review was initiated to describe published studies, identify gaps in knowledge, and propose future research goals regarding the disease pathology of ACO, especially the airway remodelling changes and inflammation aspects. Airway remodelling occurs in asthma and COPD, but there are differences in the structures affected and the prime anatomic site at which they occur. Reticular basement membrane thickening and cellular infiltration with eosinophils and T-helper (CD4+) lymphocytes are prominent features of asthma. Epithelial squamous metaplasia, airway wall fibrosis, emphysema, bronchoalveolar lavage (BAL) neutrophilia and (CD8+) T-cytotoxic lymphocyte infiltrations in the airway wall are features of COPD. There is no universally accepted definition of ACO, nor are there clearly defined pathological characteristics to differentiate from asthma and COPD. Understanding etiological concepts within the purview of inflammation and airway remodelling changes in ACO would allow better management of these patients.

Asthma-COPD Overlap: What Are the Important Questions?

Asthma-COPD overlap (ACO) is a heterogeneous condition that describes patients who show persistent airflow limitation with clinical features that support both asthma and COPD. Although no single consensus definition exists to diagnose this entity, common major criteria include a strong bronchodilator reversibility or bronchial hyperreactivity, a physician diagnosis of asthma, and a ≥ 10-pack-year cigarette smoking history. The prevalence of ACO ranges from 0.9% to 11.1% in the general population, depending on the diagnostic definition used. Notably, patients with ACO experience greater symptom burden, worse quality of life, and more frequent and severe respiratory exacerbations than those with asthma or COPD. The underlying pathophysiologic features of ACO have been debated. Although emerging evidence supports the role of environmental and inhalational exposures in its pathogenesis among patients with a pre-existing airway disease, biomarker profiling and genetic analyses suggest that ACO may be a heterogeneous condition, but with definable characteristics. Early-life factors including childhood-onset asthma and cigarette smoking may interact to increase the risk of airflow obstruction later in life. For treatment options, the population with ACO historically has been excluded from therapeutic trials; therefore strong, evidence-based recommendations are lacking beyond first-line inhaler therapies. Advanced therapies in patients with ACO are selected according to disease phenotypes and are based on extrapolated data from asthma and COPD. Research focused on defining biomarkers and evidence-based treatment options for ACO is needed urgently.

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.

Eosinophilia and fractional exhaled nitric oxide levels in chronic obstructive lung disease

Introduction

COPD is a heterogeneous disorder with varied phenotypes. We aimed to determine the prevalence of asthma history, peripheral eosinophilia and elevated FeNO levels along with the diagnostic utility of peripheral eosinophilia in identifying airway eosinophilic inflammation.

Methods

National Health and Nutrition Examination Survey data were analysed for the study period 2007–2010. Subjects aged ≥40 years with postbronchodilator FEV₁/FVC ratio <0.70 were included. Receiver operator curve analysis was performed for sensitivity analysis. A p value of <0.001 is considered statistically significant.

Results

A total of 3 110 617 weighted COPD cases were identified; predominantly male (64.4%) and non-Hispanic whites (86.1%). Among our COPD subjects, 14.6% had a history of doctor diagnosed asthma, highest among females and other race Americans. The overall prevalence of peripheral eosinophilia is 36%, 38.3% among COPD subjects with asthma history, and 35.6% among COPD without asthma history. The overall prevalence of elevated FeNO ≥25 ppb is 14.3%; 28.7% among COPD subjects with asthma history and 13.0% among COPD without asthma history.

Discussion

The prevalence of FeNO levels ≥25 ppb and peripheral eosinophilia was significantly higher among COPD subjects with asthma compared with COPD without asthma history. Not all COPD subjects with peripheral eosinophilia and elevated FeNO levels have a reported history of asthma. Our study supports clinically phenotyping COPD subjects with eosinophilic inflammation be independent of their asthma history and peripheral eosinophilia can be used as a surrogate marker in resource-limited settings.

Update on Asthma-COPD Overlap (ACO): A Narrative Review

Although chronic obstructive pulmonary disease (COPD) and asthma are well-characterized diseases, they can coexist in a given patient. The term asthma-COPD overlap (ACO) was introduced to describe patients that have clinical features of both diseases and may represent around 25% of COPD patients and around 20% of asthma patients. Despite the increasing interest in ACO, there are still substantial controversies regarding its definition and its position within clinical guidelines for patients with obstructive lung disease. In general, most definitions indicate that ACO patients must present with non-reversible airflow limitation, significant exposure to smoking or other noxious particles or gases, together with features of asthma. In patients with a primary diagnosis of COPD, the identification of ACO has therapeutic implication because the asthmatic component should be treated with inhaled corticosteroids and some studies suggest that the most severe patients may respond to biological agents indicated for severe asthma. This manuscript aims to summarize the current state-of-the-art of ACO. The definitions, prevalence, and clinical manifestations will be reviewed and some innovative aspects, such as genetics, epigenetics, and biomarkers will be addressed. Lastly, the management and prognosis will be outlined as well as the position of ACO in the COPD and asthma guidelines.

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.

Osteoporosis and fracture risk associated with inhaled corticosteroid use among Swedish COPD patients: the ARCTIC study

The effect of inhaled corticosteroids (ICS) on the risk of osteoporosis and fracture in patients with chronic obstructive pulmonary disease (COPD) remains uncertain. The aim of this study was to assess this risk in patients with COPD.Electronic medical record data linked to National Health Registries were collected from COPD patients and matched reference controls at 52 Swedish primary care centres from 2000 to 2014. The outcomes analysed were the effect of ICS on all fractures, fractures typically related to osteoporosis, recorded osteoporosis diagnosis, prescriptions of drugs for osteoporosis and a combined measure of any osteoporosis-related event. The COPD patients were stratified by the level of ICS exposure.A total of 9651 patients with COPD and 59 454 matched reference controls were analysed. During the follow-up, 19.9% of COPD patients had at least one osteoporosis-related event compared with 12.9% of reference controls (p<0.0001). Multivariate analysis in the COPD population demonstrated a dose-effect relationship, with high-dose ICS being significantly associated with any osteoporosis-related event (risk ratio 1.52 (95% CI 1.24-1.62)), while the corresponding estimate for low-dose ICS was 1.27 (95% CI 1.13-1.56) compared with COPD patients not using ICS. A similar dose-related adverse effect was found for all four of the specific osteoporosis-related events: all fractures, fractures typically related to osteoporosis, prescriptions of drugs for osteoporosis and diagnosis of osteoporosis.We conclude that patients with COPD have a greater risk of bone fractures and osteoporosis, and high-dose ICS use increased this risk further.

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.

Nationwide quality assessment of treatment for chronic obstructive pulmonary disease

Background

Chronic obstructive pulmonary disease (COPD) requires careful ambulatory care. If treatment is effective, exacerbation and hospitalization can be preventable. Appropriate management is important; the disease prevalence is high, as is the demand on healthcare resources. Here, we have reported the results of nationwide quality assessment performed with the aims of improving patient management, reducing progression to severe status, and minimizing medical care expenses.

Methods

The Health Insurance Review and Assessment Service (HIRA) engaged in quality assessment three times from May 2014 to April 2017. Medical care institutions were evaluated in terms of the pulmonary function test (PFT), patient revisit, and inhaled bronchodilator prescription rates.

Results

The numbers of patients assessed were 141,782, 142,790, and 143,339 in years 1, 2, and 3, respectively; the numbers of medical care institutions assessed were 6,691, 6,722, and 6,470, respectively. The PFT implementation rates were 58.7%, 62.5%, and 67.9% for years 1, 2, and 3, respectively; these rates were highest for tertiary hospitals, followed by general and local hospitals, as well as primary healthcare clinics. The repeat visit rates were 85.5%, 92.1%, and 85.0% for years 1, 2, and 3, respectively; these rates were highest for general hospitals, followed by local and tertiary hospitals, and primary healthcare clinics. The inhaled bronchodilator prescription rates were 67.9%, 71.2%, and 76.9% for years 1, 2, and 3, respectively; these rates increased with increasing hospital grade.

Conclusions

The PFT and inhaled bronchodilator prescription rates improved over the 3-year nationwide quality assessment period.

Chronic obstructive pulmonary disease research by using big data

As the information technology develops, large amount of data has been stored. The digitalisation of the health-care system enables researchers to use big data easily. Big data have been utilised for valuable source for chronic obstructive pulmonary disease (COPD) research. Various sources of data are now available including nationwide claim data and primary care database. Recently, web data are also used in COPD research. Each different data source has strengths and weaknesses. Merging different data can overcome the limitation of big data research. Future direction of big data research is to integrate multiple big data.

Prescribing Pathways to Triple Therapy: A Multi-Country, Retrospective Observational Study of Adult Patients with Chronic Obstructive Pulmonary Disease

Introduction

Maintenance treatment strategies in COPD recommend inhaled corticosteroid (ICS) + long-acting muscarinic antagonist (LAMA) + long-acting β₂-agonist (LABA) triple therapy after initial dual therapy. Little is known about how treatment pathways to triple therapy vary across countries in clinical practice.

Methods

This multi-country, retrospective cohort study (conducted 1 January 2005–1 May 2016) included patients with a COPD diagnosis, and (UK only) evidence of smoking history, or (France, Italy, Germany, and Australia) an indicator confirming COPD diagnosis, a first instance of triple therapy recorded during the study period and ≥ 12 months of data prior to this date. Treatment pathways to triple therapy were analyzed in patients whose first instance of triple therapy was on or after the initial COPD diagnosis. The proportion of patients who initiated triple therapy prior to initial COPD diagnosis was also estimated. Meta-analyses of the main results were performed.

Results

In 130,729 patients across all countries, mean age (standard deviation) ranged from 63.4 (10.4) years (Germany) to 69.8 (9.9) years (Italy), and median time (interquartile range) from initial COPD diagnosis to first prescription of triple therapy ranged from 16.9 (5.7–36.2) months (Australia) to 42.5 (13.9–87.4) months (UK). ICS + LABA was the most common treatment pathway prior to triple therapy in the UK, Germany, and Italy (27.3%–31.6%); no previous maintenance therapy prior to triple therapy was the most common pathway in France and Australia (32.5% and 37.9%, respectively). Meta-analyses provided a pooled estimate of 20.4% (95% confidence interval: 13.8%–29.1%) for the proportion of patients initiating triple therapy at or before initial COPD diagnosis.

Conclusions

In this retrospective cohort study, treatment pathways to triple therapy were diverse within and between countries. The differing impact of treatments may affect quality of life and disease control in patients with COPD. Further analyses should investigate factors influencing pathways to triple therapy.

Acute exacerbations of COPD and risk of lung cancer in COPD patients with and without a history of asthma

Rationale

There is limited knowledge on the effect of acute exacerbations in chronic obstructive pulmonary disease (AECOPD) on lung cancer risk in COPD patients with and without a history of asthma. This study aims to examine whether AECOPD is associated with risk of lung cancer, and whether the effect depends on a history of asthma.

Methods

In the GenKOLS study of 2003–2005, 852 subjects with COPD performed spirometry, and filled out questionnaires on smoking habits, symptoms and disease history. These data were linked to lung cancer data from the Cancer Registry of Norway through 2013. AECOPD, measured at baseline was the main predictor. To quantify differences in lung cancer risk, we performed Cox-proportional hazards regression. We adjusted for sex, age, smoking variables, body mass index, and lung function.

Measurements and results

During follow-up, 8.8% of the subjects with, and 5.9% of the subjects without exacerbations were diagnosed with lung cancer. Cox regression showed a significant increased risk of lung cancer with one or more exacerbations in COPD patients without a history of asthma, HRR = 2.77 (95% CI 1.39–5.52). We found a significant interaction between a history of asthma and AECOPD on lung cancer.

Conclusions

AECOPD is associated with an increased risk of lung cancer in COPD patients without a history of asthma.

Fractional Exhaled Nitric Oxide as an Inflammatory Biomarker in Chronic Obstructive Pulmonary Disease (COPD) with or without Concurrent Diagnosis of Asthma: The Canadian Cohort Obstructive Lung Disease (CanCOLD)

We studied whether fractional exhaled nitric oxide (F _ENO) can differentiate chronic obstructive pulmonary disease (COPD) with concurrent diagnosis of asthma from COPD-only as well as its ability to predict disease severity and progression. This study was embedded in the Canadian Cohort Obstructive Lung Disease (CanCOLD). Subjects of ≥40 years old completed F _ENO measurements were subdivided into four groups, including COPD (N = 86 [COPD-only (N = 35) and COPD with concurrent diagnosis of asthma (N = 51)], healthy (N = 72), and at risk (N = 151). Three of the most common clinical definitions were used for characterizing COPD with concurrent diagnosis of asthma: 1) atopy and self-reported physician diagnosis of asthma, 2) ≥12% and ≥200 ml post-bronchodilator FEV1; 3) self-reported physician diagnosis of asthma. F _ENO values were classified using quartiles and the American Thoracic Society (ATS) guideline 2011. Compared to COPD-only, more COPD with concurrent diagnosis of asthma had a significant F _ENO50 level of [Formula: see text] 33.5 ppb (fourth quartile) than COPD-only (p = 0.045, 0.011, and 0.006, for definition 1, 2, and 3, respectively). Considering the ATS guideline 2011, fewer COPD with concurrent diagnosis of asthma had F _ENO50 < 25 than COPD-only, which was statistically significant with definition 1 and 3 (p = 0.038 and 0.026, respectively). F _ENO as a biomarker has the potential to be used as a complementary value for differentiating COPD with concurrent diagnosis of asthma from COPD-only. Further studies should be conducted on validated definitions of COPD with concurrent diagnosis of asthma, which may include a reference to the type of airway inflammation in addition to the clinical definition.

Relationship Between Changes in Inhalation Treatment Level and Exacerbation of Chronic Obstructive Pulmonary Disease: Nationwide the Health Insurance and Assessment Service Database

Background and Objective

Maintaining adequacy in chronic obstructive pulmonary disease (COPD) care is essential to sustain an adequate level of care. We aimed to assess the current status of COPD quality control and the influence of inhaler changes on disease-related health care utilization.

Methods

The Health Insurance Review and Assessment Service (HIRA) nationwide database for reimbursed insurance claims from all medical institutions in South Korea from May 2014 to April 2017 was investigated. COPD care quality was assessed by the performance rate of spirometry, the percentage of persistent visit patients and patients prescribed a bronchodilator. The number of severe exacerbations was evaluated.

Results

A total of 68,942 COPD patients were included for 3 years of longitudinal analyses. The overall spirometry enforcement rate was just over 50%, the percentage of regular follow-up patients was over 85%, and bronchodilators were prescribed to over 80% of the patients. COPD-related hospitalization or ER visit rates were 16.6%, 15.3%, and 17.8% for three consequent assessments, respectively. Inhaler changes were analyzed between the first and second assessments: 57.1% were maintained, 0.4% were changed to another class, 9% were escalated, and 5.2% were de-escalated. Only in the escalated group, especially those who changed from the mono to dual inhaler and dual to triple inhaler, had fewer hospitalizations or ER visits.

Conclusion

Adequacy of COPD care status was not that high considering the low-enforcement rate of spirometry, but most patients were prescribed a bronchodilator and regularly followed up. Those who escalated inhaler treatment experienced less health care utilization.

Identification and definition of asthma-COPD overlap: The CanCOLD study

BACKGROUND AND OBJECTIVE

Lack of consensus on diagnosis of ACO limits our understanding of the impact, management and outcomes of ACO. The present observational study aims to describe the prevalence, clinical characteristics and course of individuals with ACO based on various definitions used in clinical practice.

METHODS

We included individuals with COPD from the prospective, multisite CanCOLD study and defined subjects with ACO using seven definitions commonly used in the literature.

RESULTS

Data including questionnaires, lung function and CT scans were analysed from 522 individuals with COPD who were randomly recruited from the population. Among them, 264 fulfilled at least one of the seven definitions of ACO. Prevalence of ACO varied from 3.8% to 31%. Regardless of the definition, individuals with ACO had worse outcomes (lung function and higher percentage of fast decliners, symptoms and exacerbations, health-related quality of life and comorbidities) than the remaining patients with COPD. Conversely, patients with non-ACO had higher emphysema and bronchiolitis scores. The three definitions that included atopy and/or physician diagnosis of asthma identified subjects who differed significantly from patients with COPD. The two ACO definitions with post-bronchodilator reversibility were concordant with COPD and were the least stable, with less than 50% of the patients from each group maintaining reversibility over visits.

CONCLUSION

Atopy and physician-diagnosed asthma are more distinguishing characteristics to identify ACO. This finding needs to be validated using measures of airway inflammation and other specific biomarkers.

Effects of PM10 on mortality in pure COPD and asthma-COPD overlap: difference in exposure duration, gender, and smoking status

We investigated the effects of particulate matter (PM) on mortality in patients diagnosed with asthma-COPD overlap (ACO) or ‘pure COPD’. Subjects from the National Health Insurance Service–National Sample Cohort of Korea, who were aged 40 years or above and had newly diagnosed COPD since 2009 were selected. Finally, 6,313 patients were enrolled and divided into ‘pure COPD’ and ACO groups. Average PM₁₀ exposure data were obtained using Kriging interpolation from 2001 to 2013. Hazard ratios(HR) were estimated using a time-varying Cox regression model. Exposure to PM₁₀ for 1, 3, and 6 months was associated with an increase in non-accidental mortality in the entire COPD group, especially the ACO group. When a stratified analysis of 3-month exposure was performed by sex, the highest HR was found in women with ACO (HR = 1.153; 95% confidence intervals [CI]: 1.121, 1.185). A stratified analysis according to smoking status showed that ACO patients had the highest HR among never smokers (HR = 1.151; 95% CI; 1.124, 1.178). Average exposure to PM₁₀ was associated with non-accidental mortality in patients with COPD, especially those diagnosed with ACO. In addition, the adverse effects of PM₁₀ exposure are more severe in women and never-smokers.

Effect of Inhaled Corticosteroids on Exacerbation of Asthma-COPD Overlap According to Different Diagnostic Criteria

BACKGROUND

Few reports have investigated the efficacy of using inhaled corticosteroid (ICS)-containing inhalers to treat patients with asthma-chronic obstructive pulmonary disease (COPD) overlap (ACO).

OBJECTIVE

To investigate the effect of ICS treatment on patients with ACO using 5 sets of diagnostic criteria.

METHODS

Patients with stable COPD enrolled in the Korean COPD subgroup study cohort were assessed for asthma overlap. Patients who were prospectively followed up for 1 year were included in an exacerbation analysis.

RESULTS

Among 1067 patients with COPD, 138 (12.9%), 32 (3.0%), 171 (16%), 221 (20.7%), and 264 (24.7%) were classified as having ACO by the Global Initiative for Asthma (GINA)/Global Initiative for Chronic Obstructive Lung Disease (GOLD) criteria, the American Thoracic Society roundtable criteria, the modified Spanish criteria, the updated Spanish criteria, and specialists' diagnoses, respectively. According to the specialists' diagnoses, the ACO exacerbation rate was higher than that for COPD alone (incidence rate ratio [IRR] = 1.65; P < .01), even after adjustment for covariates. Patients with ACO who used ICSs experienced less exacerbation, according to the specialists' diagnoses and the GINA/GOLD criteria (IRR = 0.55, P = .026; IRR = 0.69, P = .046, respectively). The only factor associated with a decrease in ACO exacerbation after ICS use was a blood eosinophil count of ≥300 cells/μL (IRR = 0.52, P = .03) irrespective of the diagnosis of ACO by any set of criteria.

CONCLUSIONS

This study suggests that ICS treatment can decrease the risk of exacerbation in patients with ACO, and that a blood eosinophil count of ≥300 cells/μL can predict the response to ICS treatment.

Clinical Characteristics Of Patients With Asthma COPD Overlap (ACO) In Australian Primary Care

Purpose

Many older adults with a history of smoking and asthma develop clinical features of both asthma and COPD, an entity sometimes called asthma-COPD overlap (ACO). Patients with ACO may be at higher risk of poor health outcomes than those with asthma or COPD alone. However, understanding of ACO is limited in the primary care setting and more information is needed to better inform patient management. We aimed to compare the characteristics of patients with ACO or COPD in Australian general practices.

Patients and methods

Data were from the RADICALS (Review of Airway Dysfunction and Interdisciplinary Community-based care of Adult Long-term Smokers) trial, an intervention study of an interdisciplinary community-based model of care. Baseline demographic and clinical characteristics, pre- and post-bronchodilator spirometry, dyspnoea and St. George’s Respiratory Questionnaire scores were compared between 60 ACO patients and 212 with COPD alone.

Results

Pre-bronchodilator Forced Expiratory Volume in 1 second (mean±SD 58.4±14.3 vs 67.5±20.1% predicted) and Forced Vital Capacity (mean 82.1±16.9 v 91.9±17.2% predicted) were significantly lower in the ACO group (p<0.001), but no difference was found in post-bronchodilator spirometry. Demographic and clinical characteristics, dyspnoea, quality of life, comorbidities and treatment prescribed did not differ significantly between groups.

Conclusion

This is the first study describing the clinical characteristics of ACO patients in Australian general practices. Our finding of lower pre-bronchodilator lung function in the ACO group compared to those with COPD reinforces the importance of spirometry in primary care to inform management.

Trial registration

Australian New Zealand Clinical Trials Registry ACTRN12614001155684.

Mortality of patients with chronic obstructive pulmonary disease: a nationwide populationbased cohort study

BACKGROUND/AIMS

Chronic obstructive pulmonary disease (COPD) is a major cause of mortality in the world. There are no population-based studies on longterm mortality in COPD patients in Korea.

METHODS

Using the large, population-based, National Health Insurance Service- National Sample Cohort (NHIS-NSC), we identified COPD patients using the International Classification of Disease-Tenth Revision (ICD-10) and prescription details in the NHIS-NSC during 2003 to 2013. We analyzed the survival curves of COPD patients by sex, age, and cause of death.

RESULTS

A total of 14,127 individuals older than 40 years were diagnosed with COPD. There were a total of 3,695 deaths (26.2%) in COPD patients during the study period. The 5-year mortality of COPD patients was 25.4% (29.9% in males and 19.1% in females). The mortality rate increased rapidly with age. The most common cause of death in COPD was chronic lower respiratory disease.

CONCLUSION

This study described long-term mortality in COPD patients in Korea. Higher mortality was observed in males, and it was closely related to age.

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.

Asthma-COPD Overlap-A Discordance Between Patient Populations Defined by Different Diagnostic Criteria

BACKGROUND

The concordance between asthma-chronic obstructive pulmonary disease overlap (ACO) defined according to Global Inititative for Asthma (GINA)/Global Initiative for Chronic Obstructive Lung Disease (GOLD) and other diagnostic criteria is unknown.

OBJECTIVE

To assess the concordance between different ACO definitions and to estimate the definition-based ACO prevalence and characteristics.

METHODS

A prospective, real-life study based on a 32-item data set was performed in a mixed population of patients with asthma and chronic obstructive pulmonary disease (COPD). Five different definitions of ACO, including the GINA/GOLD criteria, were analyzed.

RESULTS

A total of 1609 patients were included in the final analysis. Application of Venn diagram for ACO populations resulted in 31 ACO subpopulations, which were further reduced to 6 separate populations by introducing a rank order for the analyzed definitions to classify patients from intersecting groups. Overall, the level of agreement between different ACO definitions was poor. Cohen kappa coefficient for the agreement between ACO GINA/GOLD definition and other ACO definitions varied from 0.06 to 0.21. Only 2 patients (0.12%) met all the ACO definitions. Definition-based ACO prevalence ranged between 3.8% (Spanish criteria) and 18.4% (clinician's diagnosis). A total of 573 (33.4%) patients met the criteria from at least 1 ACO definition. Patients who could not be classified as suffering from "pure" asthma, "pure" COPD, or ACO accounted for as much as 27.5% of the whole investigated group. The most severe symptoms were observed in patients with ACO defined as COPD and asthma diagnosed at age less than 40 years.

CONCLUSIONS

The current ACO definitions identify distinct populations that share only a small number of common features and present with different disease phenotypes. ACO prevalence is highly variable, depending on the definition applied.

Controversies in Allergy: Is Asthma Chronic Obstructive Pulmonary Disease Overlap a Distinct Syndrome That Changes Treatment and Patient Outcomes?

While asthma/COPD overlap (ACO), like both asthma and COPD alone, is not a distinct syndrome, nonetheless it does have features that distinguish it from asthma and COPD only. Similar to the latter obstructive pulmonary disorders, it most likely represents a complex spectrum of diseases comprising several different phenotypes and underlying pathophysiologies. It also not yet clear how ACO is best defined, i.e., by clinical features (age, physiology, bronchodilator responsiveness, symptom variability, history of asthma), biomarkers or a combination of these features. The lack of generally agreed-on diagnostic criteria probably accounts for the marked heterogeneity of the results of published surveys of its prevalence. Until a true consensus is achieved regarding the definition of ACO, it will not be possible to determine with confidence not only its prevalence, but also its natural history (outcomes), its underlying biology or its optimal treatment based on findings from randomized controlled clinical trials focused specifically on patients with well-defined ACO.

The Economic Effect of Early Management in Patients with Early Chronic Obstructive Pulmonary Disease: Results from a Population-Based Nationwide Survey

PURPOSE

The economic effect of regular follow-up and early management in patients with early chronic obstructive pulmonary disease (COPD) has not yet been clarified. Therefore, this study aimed to estimate the economic effect of regular follow-up and early management in these patients.

METHODS

Patients with early COPD were identified from the Korea National Health and Nutrition Examination Survey. We analyzed medical utilization and cost for 2 years without any missing data by using the Korean National Health Insurance data. Patients with routine healthcare maintenance were defined as, after diagnosis, those with regular visits to the hospital and receiving early management of COPD.

RESULTS

Among 1204 patients with early COPD, the patients who were classified as the group with routine healthcare maintenance (69/146; 47.3%) and the group with intermittent healthcare user (79/1058; 7.5%) visited to hospital for the next 2 years. The patients with routine healthcare maintenance had lower cost of inpatient service and frequencies of emergency room (ER) visit and intensive care unit (ICU) admission than intermittent healthcare users (cost of inpatient service, $4595 vs. $4953 per person; ER visit, 7.2 vs. 11.5; ICU admission, 4.3 vs. 7.7). Even in patients with COPD and FEV₁ ≥ 80, early intervention through follow-up reduced the cost of inpatient service because these patients could have had less severe acute exacerbations than intermittent healthcare users.

CONCLUSION

Patients with early COPD, even those with FEV₁ ≥ 80, need regular follow-up for early management and disease control as well as for reducing the socioeconomic burden of the disease.

Longitudinal comparison of outcomes in patients with smoking-related asthma-COPD overlap and in non-smoking asthmatics with incomplete reversibility of airway obstruction

Background

There is a need to characterize the impact of the smoking status on the clinical course of asthmatics with incomplete reversibility of airway obstruction (IRAO).

Objective

To compare longitudinal health care use, symptom control, and medication needs between smoking and non-smoking asthmatics with IRAO.

Materials and methods

This was a 12-month follow-up of a cross-sectional study comparing asthmatics with IRAO according to their tobacco exposure. One group had a tobacco exposure ≥20 pack-years and was considered to have asthma-COPD overlap (ACO) and the second with a past tobacco exposure <5 pack-years was considered as non-smokers with IRAO (NS-IRAO). Study participants were contacted by telephone every 3 months to document exacerbation events and symptom control.

Results

A total of 111 patients completed all follow-up telephone calls: 71 ACO and 40 NS-IRAO. The number of exacerbations per patient over the 12-month follow-up was similar in both groups. However, ACO reported worse symptom control throughout the follow-up as compared to NS-IRAO, although no significant variations within a group were observed over the study period.

Conclusion

Although asthma control scores were poorer in ACO patients over 1 year compared to NS-IRAO, exacerbation rate was similar and low in both groups of asthmatics. These observations suggest that poorer asthma control in ACO was not driven by the number of exacerbations but may reflect the influence of chronic airway changes related to the COPD component.

Nonallergic Triggers and Comorbidities in Asthma Exacerbations and Disease Severity

Asthma triggers are exogenous or endogenous factors that could worsen asthma acutely to cause an exacerbation, or perpetuate chronic symptoms and airflow limitation. Because it is well known that recent asthma exacerbations and poor symptom control are strong predictors of future disease activity, it is not surprising that the number of (allergic or nonallergic) asthma triggers in the environment correlates with the disease-related quality of life. There is a need to identify and avoid specific triggers as the centerpiece of disease management, especially in those with heightened sensitivity to certain factors.

Association between continuity of care and emergency department visits and hospitalization in senior adults with asthma-COPD overlap

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COC enables healthcare more effectively and improves clinical outcomes.

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COC is also important for elderly ACO patients.

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Increasing COC is beneficial for elderly patients with ACO in disease management.

Objective

To investigate associations between continuity of care (COC) and emergency department (ED) visits and hospitalization for chronic obstructive pulmonary disease (COPD) or asthma among elderly adults with asthma-COPD overlap (ACO).

Methods

A retrospective cohort study was performed using the Taiwan National Health Insurance research database. A total of 1141 ACO patients aged ≥65 years during 2005–2011 were observed and followed for 2 years. The Bice and Boxerman COC index (COCI) was used to evaluate COC by considering ambulatory care visits duo to COPD or asthma in the first year; ED visits and hospitalization for COPD or asthma were identified in the subsequent year, respectively. The COCI was divided into three levels (COCI < 0.3= low, 0.3 ≤ COCI<1=medium, COCI = 1=high). The Cox model was used to estimate the hazard ratio (HR) for ED visits and hospital admissions due to COPD or asthma.

Results

The average COCI was 0.55. 21.3% patients received outpatient care from a single physician. Compared to patients with high COC, those with low and medium COC had a higher risk of ED visits (aHR = 2.80 and 2.69, P < .01) and admissions (aHR = 1.80 and 1.72, P < .05).

Conclusion

Increasing COC is beneficial for elderly patients with ACO in disease management. Policymakers could create effective pay-for-performance programs for the elderly ACO population to enhance COC and improve care outcomes.

Direct and Indirect Costs of Chronic Obstructive Pulmonary Disease in Korea

Background

Understanding the burden of disease is important to establish cost-effective treatment strategies and to allocate healthcare resources appropriately. However, little reliable information is available regarding the overall economic burden imposed by chronic obstructive pulmonary disease (COPD) in Korea.

Methods

This study is a multicenter observational research on the COPD burden in Korea. Total COPD costs were comprised of three categories: direct medical, direct non-medical, and indirect costs. For direct medical costs, institutional investigation was performed at 13 medical facilities mainly based on the claims data. For direct non-medical and indirect costs, site-based surveys were administered to the COPD patients during routine visits. Total costs were estimated using the COPD population defined in the recent report.

Results

The estimated total costs were approximately 1,245 million US dollar (1,408 billion Korean won). Direct medical costs comprised approximately 20% of the total estimated costs. Of these, formal medical costs held more than 80%. As direct non-medical costs, nursing costs made up the largest percentage (39%) of the total estimated costs. Costs for COPD-related loss of productivity formed four fifths of indirect costs, and accounted for up to 33% of the total costs.

Conclusion

This study shows for the first time the direct and indirect costs of COPD in Korea. The total costs were enormous, and the costs of nursing and lost productivity comprised approximately 70% of total costs. The results provide insight for an effective allocation of healthcare resources and to inform establishment of strategies to reduce national burden of COPD.

Determinants of incident asthma-COPD overlap: a prospective study of 55,110 middle-aged adults

Background and aim

Knowledge of the impact of social determinants driving asthma– chronic obstructive pulmonary disease overlap (ACO) is lacking. Our objective was to identify determinants of incident ACO.

Methods

A total of 55,053 adults (50–64 years) enrolled in the Danish Diet, Cancer, and Health cohort (1993–97) was followed in the National Patient Registry for admissions for asthma (DJ45–46) and chronic obstructive pulmonary disease (COPD; DJ40–44) and vital status. Incident ACO was defined as at least one hospital admission for both asthma and COPD (different time points, one after baseline). Detailed case history was obtained at baseline. Cox proportional hazards model was used to examine associations between possible determinants and incident ACO, in terms of hazard ratio (HR) and 95% confidence interval (CI).

Results

During follow-up, 561 incident cases of ACO were identified. Age (HR 4.4, 95% CI 3.3–5.9, age group 60–65 years), current smoking (HR 3.6, 95% CI 2.8–4.6), unemployment (HR 1.5, 95% CI 1.2–1.8), and being divorced (HR 1.5, 95% CI 1.2–1.9) determined a higher risk of incident ACO, whereas the opposite was found for leisure-time physical activity (HR 0.7, 95% CI 0.6–0.8) and high educational level (HR 0.7, 95% CI 0.5–0.9). In contrast to ACO, preexisting myocardial infarction (MI; HR 1.5, 95% CI 1.2–1.8) and stroke (HR 1.5, 95% CI 1.2–1.9) were associated with a higher risk of COPD.

Conclusion

Incident ACO is to a large extent determined by factors related to lifestyle and socioeconomic status.

Blood eosinophils and inhaled corticosteroids in patients with COPD: systematic review and meta-analysis

Background

COPD is a highly heterogeneous disease. Potential biomarkers to identify patients with COPD who will derive the greatest benefit from inhaled corticosteroid (ICS) treatment are needed. Blood eosinophil count can serve as a predictive biomarker for the efficacy of ICS treatment. The aim of this systematic review and meta-analysis was to assess whether a blood eosinophil count of ≥2% in patients undergoing ICS therapy was associated with a greater reduction in COPD exacerbation rate and pneumonia incidence.

Materials and methods

An electronic search was performed using the keywords "COPD", "eosinophil", and "clinical trial" in the PubMed and EMBASE databases to retrieve articles, up to 2017, relevant to our focus. Data were extracted, and a meta-analysis was conducted using RevMan 5 (version 5.3.5).

Results

Five studies comprising 12,496 patients with moderate-to-very severe COPD were included. At baseline, 60% of the patients had ≥2% blood eosinophils. Our meta-analysis showed a 17% reduction in exacerbation of moderate/severe COPD in patients with ≥2% blood eosinophils undergoing ICS therapy compared to the non-ICS/ICS withdrawal/placebo group. The difference between the two types of treatment was significant (risk ratio [RR], 0.816; 95% CI, 0.67-0.99; P=0.03). Furthermore, the risk of pneumonia-related events was significantly increased in the subgroup with eosinophil count ≥2% undergoing ICS-containing treatments (RR, 1.969; 95% CI, 1.369-2.833; P<0.001). There was no significant difference in the subgroup with eosinophil count <2% (RR, 1.29; 95% CI, 0.888-1.879; P<0.181).

Conclusion

The results of our meta-analysis suggest that the 2% threshold for blood eosinophils could accurately predict ICS treatment response in patients with COPD, but increased the risk of pneumonia.

Differences in prevalence of asthma-COPD overlap according to different criteria

Asthma and chronic obstructive pulmonary disease (COPD) are common chronic airway diseases. Overlap in the clinical features of these 2 diseases is observed in many cases, and thus, the concept of asthma-COPD overlap (ACO) has recently been proposed. However, the definition of ACO and the clinical significance remains to be determined.We evaluated the prevalence and risk of acute exacerbation in ACO among Korean COPD patients as defined by modified Spanish criteria and American Thoracic Society (ATS) Roundtable criteria.The prevalence of ACO was 47.7% (660/1383) by modified Spanish criteria and 1.9% (26/1383) by ATS Roundtable criteria. ACO, regardless of criteria, did not significant affect the exacerbation risk during at least 1-year follow-up period.Substantial discrepancies were found in the prevalence and outcome of ACO according to different diagnostic criteria, which would compromise implementation of ACO before the definition is established.

Nationwide use of inhaled corticosteroids by South Korean asthma patients: an examination of the Health Insurance Review and Service database

BACKGROUND

Previous studies have found that the prescription rates of inhaled corticosteroid (ICS) were considerably low although it is recommended as the optimal asthma treatment. The aim of this study was to analyze the current status of ICS prescription for asthma patients in the South Korea.

METHODS

We evaluated quality assessment data based on nationwide Health Insurance Review and Service (HIRA) database from July 2013 to June 2014. ICS prescription rates in asthma patients were analyzed by types and specialty of medical institutions. Also, we graded medical institutions by their ICS prescription rate. In addition, ICS prescription rates were calculated by patient gender, age, and insurance type.

RESULTS

This study included 831,613 patients and 16,804 institutions in the analysis. The overall mean ICS prescription rate was 22.58%. Tertiary hospitals had the highest mean prescription rate (84.16%) whereas primary healthcare clinics had the lowest (20.71%). By specialty, internal medicine physicians prescribed ICS more frequently compared to other specialists. Of all, 47.17% of medical institutions prescribed ICS to <10% of asthma patients, while less than 6% of institutions prescribed ICS to >80% of asthma patients. Also, we found that female and patients with age >90 or <20 years exhibited lower ICS prescription rate.

CONCLUSIONS

The ICS prescription rate was found to be inadequate, given the importance of ICS as an asthma treatment. The prescription rates were especially low in primary healthcare clinics, and by specialists in fields other than internal medicine.

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.

Overlap of Asthma and Chronic Obstructive Pulmonary Disease in Patients in the United States: Analysis of Prevalence, Features, and Subtypes

Background

Although asthma and chronic obstructive pulmonary disease (COPD) are clinically distinct diseases, they represent biologically diverse and overlapping clinical entities and it has been observed that they often co-occur. Some research and theorizing suggest there is a common comorbid condition termed asthma-chronic obstructive pulmonary disease overlap (ACO). However, the existence of ACO is controversial.

Objective

The objective of this study is to describe patient characteristics and estimate prevalence, health care utilization, and costs of ACO using claims-based diagnoses confirmed with medical record information.

Methods

Eligible patients were commercial US health plan enrollees; ≥40 years; had asthma, COPD, or ACO; ≥3 prescription fills for asthma/COPD medications; and ≥2 spirometry tests. Records for a random sample of 5000 patients with ACO were reviewed to validate claims-based diagnoses.

Results

The estimated ACO prevalence was 6% (estimated 10,250/183,521) among 183,521 full study patients. In the claims-based cohorts, the comorbidity burden for ACO was greater versus asthma but similar to COPD cohorts. Medication utilization was higher in ACO versus asthma and COPD. Mean total health care costs were significantly higher for ACO versus asthma but similar to COPD. In confirmed diagnoses cohorts, mean total health care costs (medical plus pharmacy) were lower for ACO versus COPD but similar to asthma (US $20,035; P=.56). Among confirmed cases, where there was medical record evidence, smoking history was higher in ACO (300/343, 87.5%) versus asthma cohorts (100/181, 55.2%) but similar to COPD (68/84, 81%).

Conclusions

ACO had more comorbidities, medication utilization, and costs than patients with asthma or COPD but differences were not seen after confirmation with medical records.

Neutrophil gelatinase-associated lipocalin as a complementary biomarker for the asthma-chronic obstructive pulmonary disease overlap

Background

There is no standardized definition of the asthma-chronic obstructive pulmonary disease (COPD) overlap (ACO). Although the blood eosinophil count is regarded as a biomarker for identifying ACO, it has no distinct value. This study aimed to measure plasma levels of neutrophil gelatinase-associated lipocalin (NGAL), a potential biomarker for distinguishing between ACO and non-ACO COPD.

Methods

We used the Korean cohort in the COPD in dusty area (CODA) study which included 137 subjects with COPD confirmed by spirometry. We defined ACO by a positive bronchodilator response (forced expiratory volume in 1 s, FEV₁ >12% and >200 mL from baseline) or based on a previous history of asthma. Plasma levels of NGAL were determined by enzyme immunoassay.

Results

Among the 137 subjects, 77 were ACO and 60 were non-ACO COPD. Overall, the plasma NGAL levels were 15.9±7.9 and 15.6±6.6 ng/mL for non-ACO and ACO subjects respectively, and not significantly different. However, NGAL levels were significantly higher in female subjects with ACO (17.0±6.4 vs. 11.1±4.5, P=0.01). In female subjects, NGAL levels showed a good predictive ability to discriminate between ACO and non-ACO COPD [area under the receiver operating characteristic curve (AUROC), 0.77]; the predictive ability was similar to that of the blood eosinophil count (AUROC, 0.79). There was a higher probability of discriminating ACO from non-ACO among subjects in the highest tertile of NGAL levels (odds ratio, 1.72; 95% confidence interval, 0.69-4.28; P for trend =0.01).

Conclusions

NGAL levels were significantly higher in ACO compared to non-ACO COPD in female subjects. After adjusting for gender as a confounding factor, the ability to distinguish ACO was better at higher levels of NGAL.