Use of clinical characteristics to predict spirometric classification of obstructive lung disease

Background

There is no consensus on how to define patients with symptoms of asthma and chronic obstructive pulmonary disease (COPD). A diagnosis of asthma–COPD overlap (ACO) syndrome has been proposed, but its value is debated. This study (GSK Study 201703 [NCT02302417]) investigated the ability of statistical modeling approaches to define distinct disease groups in patients with obstructive lung disease (OLD) using medical history and spirometric data.

Methods

Patients aged ≥18 years with diagnoses of asthma and/or COPD were categorized into three groups: 1) asthma (nonobstructive; reversible), 2) ACO (obstructive; reversible), and 3) COPD (obstructive; nonreversible). Obstruction was defined as a post-bronchodilator forced expiratory volume in 1 second (FEV₁)/forced vital capacity <0.7, and reversibility as a post-albuterol increase in FEV₁ ≥200 mL and ≥12%. A primary model (PM), based on patients’ responses to a health care practitioner-administered questionnaire, was developed using multinomial logistic regression modeling. Other multivariate statistical analysis models for identifying asthma and COPD as distinct entities were developed and assessed using receiver operating characteristic (ROC) analysis. Partial least squares discriminant analysis (PLS-DA) assessed the degree of overlap between groups.

Results

The PM predicted spirometric classifications with modest sensitivity. Other analysis models performed with high discrimination (area under the ROC curve: asthma model, 0.94; COPD model, 0.87). PLS-DA identified distinct phenotypic groups corresponding to asthma and COPD.

Conclusion

Within the OLD spectrum, patients with asthma or COPD can be identified as two distinct groups with a high degree of precision. Patients outside these classifications do not constitute a homogeneous group.

Presence of sarcopenia in asthma-COPD overlap syndrome may be a risk factor for decreased bone-mineral density, unlike asthma: Korean National Health and Nutrition Examination Survey (KNHANES) IV and V (2008-2011)

Background

Sarcopenia and decreased bone-mineral density (BMD) are common in elderly people, and are major comorbidities of obstructive airway disease (OAD). However, the relationship between sarcopenia and BMD in each OAD phenotype, especially asthma–COPD overlap syndrome (ACOS), is not yet clear. We aimed to evaluate differences in BMD according to the presence of sarcopenia in each OAD phenotype.

Materials and methods

Among the research subjects in KNHANES IV and V (2008–2011), 5,562 were ≥50 years old and underwent qualified spirometry and dual-energy X-ray absorptiometry. A total of 947 subjects were included in the study: 89 had asthma, 748 COPD, and 110 ACOS.

Results

In the COPD and ACOS phenotypes, T-scores were lower in the sarcopenia group than the nonsarcopenia group. Prevalence rates of osteopenia and osteoporosis were higher in the sarcopenia group than the nonsarcopenia group. (P<0.001 and P=0.017, respectively). The sarcopenia group had higher risks of developing osteopenia, osteoporosis, and low BMD than the nonsarcopenia group in the ACOS phenotype (OR 6.620, 95% CI 1.129–38.828 [P=0.036], OR 9.611, 95% CI 1.133–81.544 [P=0.038], and OR 6.935, 95% CI 1.194–40.272 [P=0.031], respectively). However, in the asthma phenotype, the sarcopenia group showed no increased risk compared with the nonsarcopenia group.

Conclusion

In the ACOS phenotype, individuals with sarcopenia had a higher prevalence rate and higher risks of osteopenia and osteoporosis than those without sarcopenia among all OAD phenotypes.

Childhood Lung Function Predicts Adult Chronic Obstructive Pulmonary Disease and Asthma-Chronic Obstructive Pulmonary Disease Overlap Syndrome

RATIONALE

The burden of chronic obstructive pulmonary disease (COPD) is increasing, yet there are limited data on early life risk factors.

OBJECTIVES

To investigate the role of childhood lung function in adult COPD phenotypes.

METHODS

Prebronchodilator spirometry was performed for a cohort of 7-year-old Tasmanian children (n = 8,583) in 1968 who were resurveyed at 45 years, and a selected subsample (n = 1,389) underwent prebronchodilator and post-bronchodilator spirometry. For this analysis, COPD was spirometrically defined as a post-bronchodilator FEV₁/FVC less than the lower limit of normal. Asthma-COPD overlap syndrome (ACOS) was defined as the coexistence of both COPD and current asthma. Associations between childhood lung function and asthma/COPD/ACOS were examined using multinomial regression.

MEASUREMENTS AND MAIN RESULTS

At 45 years, 959 participants had neither current asthma nor COPD (unaffected), 269 had current asthma alone, 59 had COPD alone, and 68 had ACOS. The reweighted prevalence of asthma alone was 13.5%, COPD alone 4.1%, and ACOS 2.9%. The lowest quartile of FEV₁ at 7 years was associated with ACOS (odds ratio, 2.93; 95% confidence interval, 1.32-6.52), but not COPD or asthma alone. The lowest quartile of FEV₁/FVC ratio at 7 years was associated with ACOS (odds ratio, 16.3; 95% confidence interval, 4.7-55.9) and COPD (odds ratio, 5.76; 95% confidence interval, 1.9-17.4), but not asthma alone.

CONCLUSIONS

Being in the lowest quartile for lung function at age 7 may have long-term consequences for the development of COPD and ACOS by middle age. Screening of lung function in school age children may identify a high-risk group that could be targeted for intervention. Further research is needed to understand possible modifiers of these associations and develop interventions for children with impaired lung function.

Asthma-like Features and Clinical Course of Chronic Obstructive Pulmonary Disease. An Analysis from the Hokkaido COPD Cohort Study

RATIONALE

Some patients with chronic obstructive pulmonary disease (COPD) have asthma-like features, such as significant bronchodilator reversibility, blood eosinophilia, and/or atopy, even if they are not clinically diagnosed as having asthma. However, the clinical significance of asthma-like features overlapping with COPD remains unclear.

OBJECTIVES

The aim of this study was to assess the effect of asthma-like features on the clinical course of patients with COPD who were adequately treated and followed-up over 10 years.

METHODS

A total of 268 patients with COPD who had been clinically considered as not having asthma by respiratory specialists were included in this study. The asthma-like features included in this study were bronchodilator reversibility (ΔFEV₁, ≥12% and ≥200 ml), blood eosinophilia (≥300 cells/μl), and atopy (positive specific IgE for any inhaled antigen). The annual changes in post-bronchodilator FEV₁ and COPD exacerbations were monitored during the first 5 years, and mortality was followed during the entire 10 years of the study.

MEASUREMENTS AND MAIN RESULTS

Fifty-seven subjects (21%) had bronchodilator reversibility, 52 (19%) had blood eosinophilia, and 67 (25%) had atopy. Subjects with blood eosinophilia had significantly slower annual post-bronchodilator FEV₁ decline; bronchodilator reversibility and atopy did not affect the annual post-bronchodilator FEV₁ decline, and none of the asthma-like features was associated with development of COPD exacerbation. Even if subjects had two or more asthma-like features, they displayed annual post-bronchodilator FEV₁ declines and exacerbation rates similar to those of subjects with one or zero asthma-like features, as well as a lower 10-year mortality rate (P = 0.02).

CONCLUSIONS

The presence of asthma-like features was associated with better clinical course in patients with COPD receiving appropriate treatment.

Expression profiling of miRNA-145 and miRNA-338 in serum and sputum of patients with COPD, asthma, and asthma-COPD overlap syndrome phenotype

Background and objectives

A new phenotype with overlapping characteristics between asthma and chronic obstructive pulmonary disease (COPD) called asthma–COPD overlap syndrome (ACOS) is emerging among inflammation diseases. To date, there is no agreement on specific criteria to define this syndrome, and the current guidelines are insufficient to classify the analogy and differences between overlap and COPD or asthma phenotypes. It would be necessary to identify new biomarkers able to identify these diseases clearly. Thus, the aim of this study was to identify a serum and supernatant of sputum microRNA (miRNA) expression profile of miRNA-145 and miRNA-338 in patients with asthma (n=13), COPD (n=31), and ACOS (n=8) and controls (n=7).

Methods

The expression was evaluated using quantitative real-time polymerase chain reaction (qRT-PCR). For statistical analysis, the ANOVA test, Kruskal–Wallis test, Mann–Whitney U-test, and Spearman’s rank correlation were used.

Results

The main finding of this work is that the expression of miRNA-338 is higher in the supernatant of different obstructive diseases than in peripheral blood, while miRNA-145 is higher only in the supernatant of asthma patients. The expression of both selected miRNAs is higher in the supernatant of asthma and COPD patients than in controls.

Conclusion

Differences in sputum miRNA expression profile were observed between patients with ACOS and asthma or COPD, which underline the potential role of miRNA as a biomarker that is able to discriminate patients with ACOS, asthma, and COPD.

Treatment trends in patients with asthma-COPD overlap syndrome in a COPD cohort: findings from a real-world survey

BACKGROUND

Asthma and chronic obstructive pulmonary disease (COPD) overlap syndrome (ACOS) is an increasingly recognized phenotype. Few randomized clinical trials have been conducted in patients with ACOS; therefore, scientific evidence concerning ACOS is scarce and a therapeutic approach remains unclear. The aim of this study was to evaluate current treatment trends for patients with ACOS, identified as those with a dual definition of asthma and COPD, in a real-world COPD cohort.

METHODS

Data were analyzed from patients with asthma and COPD in the USA, France, Germany, Italy, Spain, and the UK who participated in the 2012 and 2013 Adelphi Respiratory Disease Specific Programmes (DSPs). Patients with ACOS were identified in the COPD population; these patients had a physician-confirmed, concomitant asthma diagnosis. Physicians completed a patient record form providing information on patient and disease characteristics including prescribed respiratory treatment. Pairwise comparisons were made between the ACOS, asthma, and COPD populations using χ² tests.

RESULTS

In total, 9,042 patients with asthma-only, 7,119 patients with COPD-only, and 523 patients with ACOS (a dual diagnosis of asthma and COPD) participated in the study. The most commonly prescribed regimens were inhaled corticosteroid/long-acting β₂-agonist (ICS/LABA) + long-acting muscarinic antagonist (LAMA); (ACOS 30%, asthma 1.4%, and COPD 32%), ICS/LABA (19%, 41.5%, and 17%, respectively), and LAMA (6%, 0.4%, and 19%, respectively); 18% of patients with ACOS were not prescribed an ICS. Patients with ACOS had a significantly higher incidence of gastroesophageal reflux disease, diabetes, and obesity and experienced more exacerbations in the past year than those with COPD or asthma.

CONCLUSIONS

The majority of patients with ACOS, as defined in this research, were prescribed similar treatment to those with COPD. There is a need, however, for better treatment for patients with ACOS, as indicated by symptoms and exacerbation levels. A clearer therapeutic approach for patients with ACOS is required.

Fractional exhaled nitric oxide levels in asthma-COPD overlap syndrome: analysis of the National Health and Nutrition Examination Survey, 2007-2012

Purpose

Recent studies propose T_H2-mediated inflammation in patients with asthma–chronic obstructive pulmonary disease (COPD) overlap syndrome (ACOS). However, little is known about whether fractional exhaled nitric oxide (FeNO) differs between patients with ACOS and those with COPD alone. To address this knowledge gap, a nationally representative sample was analyzed to determine the difference in FeNO levels between patients with ACOS and those with COPD alone in the US population.

Patients and methods

This is a cross-sectional analysis of the National Health and Nutrition Examination Survey from 2007 through 2012. All subjects aged ≥40 years with COPD were identified. ACOS was defined as self-reported wheezing in past 12 months plus bronchodilator response (forced expiratory volume increase of >200 mL and >12%) or self-reported physician diagnosis of asthma.

Results

A total of 197 subjects with COPD were identified in the National Health and Nutrition Examination Survey. Of these, 23% met the criteria of ACOS. The FeNO level was higher in subjects with ACOS compared with those with COPD alone in both unadjusted (mean 21.2 ppb vs 13.0 ppb; difference, 8.2 [95% CI, 0.2 to 16.2]; P=0.045) and adjusted (difference, 8.2 [95% CI, 0.9 to 15.5]; P=0.03) analyses. Although there was no significant difference among current smokers, the FeNO level was significantly higher in non-current smokers with ACOS than nonsmokers with COPD alone (mean 31.9 ppb vs 20.3 ppb; adjusted difference, 20.5 [95% CI, 4.4 to 36.6]; P=0.02). In a sensitivity analysis using an alternative definition of ACOS, the results did not change materially. The diagnostic value of FeNO to discriminate ACOS from COPD alone was not sufficient, with the area under the curve of 0.63 (95% CI, 0.54 to 0.72).

Conclusion

By using nationally representative US data, it was found that 23% of COPD subjects met the ACOS criteria and also that the FeNO level was higher in subjects with ACOS compared with those with COPD alone, particularly in non-current smokers.

Analysis of Asthma-Chronic Obstructive Pulmonary Disease Overlap Syndrome Defined on the Basis of Bronchodilator Response and Degree of Emphysema

RATIONALE

Despite the increasing recognition of asthma-chronic obstructive pulmonary disease overlap syndrome (ACOS) as a clinical entity, it remains poorly characterized due to a lack of agreement on its definition and diagnostic criteria.

OBJECTIVES

The aim of this study was to use spirometry and computed tomography (CT) to help better define ACOS as well as to classify subjects with ACOS based on Global Initiative for Chronic Obstructive Lung Disease (GOLD) letter grade.

METHODS

We analyzed 10,192 subjects enrolled in the COPDGene Study. Subjects were non-Hispanic white or African American current or former smokers aged 45-80 years with at least a 10-pack-year smoking history. Subjects were categorized as having either ACOS with a bronchodilator response or chronic obstructive pulmonary disease with emphysema on the basis of spirometry, high-resolution CT, and a history of asthma or hay fever.

MEASUREMENTS AND MAIN RESULTS

Subjects with ACOS were younger (60.6 vs. 65.9 years old; P < 0.0001), more likely to be African American (26.8% vs. 14.4%; P < 0.0001), had a higher body mass index (29.6 vs. 25.1 kg/m(2); P < 0.0001), and were more likely to be current smokers (50.9% vs. 20.7%; P < 0.0001). The majority of subjects with ACOS were categorized as GOLD grade B. Despite less severe spirometry and CT findings in subjects with ACOS, there was no significant difference in severe or frequent exacerbations.

CONCLUSIONS

Bronchodilator responsiveness and degree of emphysema can help define ACOS. When defined on the basis of bronchodilator responsiveness and degree of emphysema, patients with ACOS represent a unique and high-risk group with distinct clinical features.

The objective evaluation of obstructive pulmonary diseases with spirometry

Airway obstruction is variable in asthma, while it is progressive and persistent in chronic bronchitis and emphysema. However, some of the patients presenting with symptoms of chronic airway diseases have clinical features of both asthma and COPD. The group with “Asthma–COPD Overlap Syndrome” (ACOS) phenotype was characterized by definitely irreversible airway obstruction accompanied by symptoms and signs of reversibility. In this study, we aimed to classify obstructive airway diseases by clinical, radiological, and pulmonary function tests. Patients at Samsun Medical Park Hospital Chest Diseases outpatient clinic were evaluated between January 2013 and April 2016, and a total of 235 patients were included in this study. Mean age of the patients was 55.3±14.5 (15–88) years, and the male/female ratio was 45/190. The baseline pulmonary function test results of the patients were as follows: mean forced vital capacity (FVC) values 2,825±1,108 (710–6,870) mL and 74.3±22.4 (24–155)%, forced expiratory volume in 1 second (FEV₁) values 1,789±774 (480–4,810) mL and 58.1±20.0 (20–130)%, FEV₁/FVC values 62.5±6.8 (39–70)%. Reversibility criteria following bronchodilator treatment were present in 107 (45.5%) patients. We specified five subgroups for patients according to their clinical, radiological, and pulmonary test findings, namely Group 1 (asthma), Group 2 (ACOS), Group 3 (chronic bronchitis), and Group 4 (emphysema). Additionally, a group of patients who had clinical and spirometric features of both asthma and chronic bronchitis in association with underlying emphysema (emphysema with chronic bronchitis and emphysema with asthma) was defined as the undifferentiated obstruction (UNDO) group. Number and percentage distribution of patients by groups were 58 (24.7%) in the asthma group, 70 (29.8%) in the ACOS group, 61 (26%) in the chronic bronchitis group, 32 (13.6%) in the emphysema group, and 14 (6%) in the UNDO group. In conclusion, in our study, the types of obstructive airway diseases could be classified based on clinical, radiological, and pulmonary function test findings into five groups, including asthma, ACOS, chronic bronchitis, emphysema, and both asthma and chronic bronchitis in association with underlying emphysema (emphysema with chronic bronchitis and emphysema with asthma) or the so-called undifferentiated obstruction. We suggest that these patient groups can be determined more accurately by studies that evaluate the association between spirometric FEV₁, FEV₁/FVC values, and reversibility ratios.

Omalizumab (anti-IgE) therapy in the asthma-COPD overlap syndrome (ACOS) and its effects on circulating cytokine levels

CONTEXT

The term "asthma-chronic obstructive pulmonary disease (COPD) overlap syndrome" (ACOS) has been applied to the condition, in which a person has clinical features of both asthma and COPD.

METHODS

The patients (N = 10) were presented to our clinic with low lung function, limited reversibility of airway obstruction, hyperinflation, abnormal body composition, dyspnea and episodic wheezing. Based on the clinical and laboratory findings, the patients were diagnosed with ACOS. Patients' serum IL-2 (sIL-2), sIL-4 sIL-6, sIL-10, sIL-17, sTNF-α and sIFN-γ levels were investigated as an apoptotic marker and a marker for inflammation.

RESULTS

Having undergone omalizumab treatment and a long-term (12 months) later, patients had a decreased IgE, fractional exhaled nitric oxide concentrations (FENO), eosinophil, neutrophils, macrophages, eosinophil cationic peptide (ECP) and sIL-4 levels.

CONCLUSION

To our knowledge, this is the first documentation of omalizumab use in ACOS. We demonstrated decreased IL-4, allergic pulmonary symptoms (dyspnea, wheezing, bronchial hyper responsiveness) and migraine attacks in the patients.

COPD assessment test and severity of airflow limitation in patients with asthma, COPD, and asthma-COPD overlap syndrome

OBJECTIVE

The COPD assessment test (CAT) consists of eight nonspecific scores of quality of life. The aim of this study was to compare the health-related quality of life and severity of airflow limitation in patients with asthma, COPD, and asthma-COPD overlap syndrome (ACOS) using the CAT.

METHODS

We examined CAT and lung functions in 138 patients with asthma, 99 patients with COPD, 51 patients with ACOS, and 44 patients with chronic cough as a control. The CAT score was recorded in all subjects, and the asthma control test was also administered to patients with asthma and ACOS. The CAT scores were compared, and the relationships between the scores and lung function parameters were analyzed.

RESULTS

The total CAT scores and scores for cough, phlegm, and dyspnea were higher in patients with ACOS than in patients with asthma and COPD. The total CAT scores were correlated with the percent predicted forced expiratory volume in 1 second only in patients with COPD. The total CAT scores and dyspnea scores adjusted by the percent predicted forced expiratory volume in 1 second were higher in patients with ACOS than in patients with COPD and asthma. The CAT scores and asthma control test scores were more closely correlated in patients with ACOS than in patients with asthma.

CONCLUSION

Patients with ACOS have higher disease impacts and dyspnea sensation unproportional to the severity of airflow limitation.