Adult Asthma Cohort Research Articles

Examining factors associated with poor metered-dose inhaler technique in a cohort of bronx patients with uncontrolled asthma

Objective Most studies investigating at-risk groups for poor inhaler technique (PT) have been in adolescents. However, evidence suggests older age correlates with PT. This study aimed to correlate patient characteristics with PT in an adult asthma cohort in the Bronx. Methods We categorized 237 patients with uncontrolled asthma by demonstration of good inhaler technique (GT) (n = 112) or PT (n = 58) at their initial visit. Independent variables included age, sex, ethnicity, language, insurance status, BMI, depression severity, and socioeconomic data. Two logistic regression models were created to assess odds of PT among independent variables at initial visit and odds of improvement in technique at follow-up. Results At the initial visit, patients with PT had a mean age of 53.74 (±13.54) versus 45.12 (±13.26) among those with GT (p= <0.001). The PT group also had a lower percentage of patients with private insurance (52.53% versus 71.15%, p = 0.037). When controlling for language, ethnicity, insurance status, and educational attainment, the odds of PT increased with age (OR, 1.051; CI, 1.017-1.087, p = 0.003) and BMI (OR, 1.065; CI, 1.010-1.123, p = 0.020). Males had lower odds of PT (OR, 0.379; CI, 0.144-0.997; p = 0.049). While insurance status did not affect odds of PT, Medicaid users had lower odds of improving technique (OR, 0.184; CI, 0.040-0.854; p = 0.031). Conclusions At baseline, individuals with PT were younger and more likely to be on a public health insurance plan. Increasing age, increasing BMI, and female sex were associated with higher odds of PT at the baseline visit, but were not associated with improvements in technique.

Species-level, metagenomic and proteomic analysis of microbe-immune interactions in severe asthma.

The airway microbiome in severe asthma has not been characterised at species-level by metagenomic sequencing, nor have the relationships between specific species and mucosal immune responses in 'type-2 low', neutrophilic asthma been defined. We performed an integrated species-level metagenomic data with inflammatory mediators to characterise prevalence of dominant potentially pathogenic organisms and host immune responses. Sputum and nasal lavage samples were analysed using long-read metagenomic sequencing with Nanopore and qPCR in two cross-sectional adult severe asthma cohorts, Wessex (n = 66) and Oxford (n = 30). We integrated species-level data with clinical parameters and 39 selected airway proteins measured by immunoassay and O-link. The sputum microbiome in health and mild asthma displayed comparable microbial diversity. By contrast, 23% (19/81) of severe asthma microbiomes were dominated by a single respiratory pathogen, namely H. influenzae (n = 10), M. catarrhalis (n = 4), S. pneumoniae (n = 4) and P. aeruginosa (n = 1). Neutrophilic asthma was associated with H. influenzae, M. catarrhalis, S. pneumoniae and T. whipplei with elevated type-1 cytokines and proteases; eosinophilic asthma with higher M. catarrhalis, but lower H. influenzae, and S. pneumoniae abundance. H. influenzae load correlated with Eosinophil Cationic Protein, elastase and IL-10. R. mucilaginosa associated positively with IL-6 and negatively with FGF. Bayesian network analysis also revealed close and distinct relationships of H. influenzae and M. catarrhalis with type-1 airway inflammation. The microbiomes and cytokine milieu were distinct between upper and lower airways. This species-level integrated analysis reveals central, but distinct associations between potentially pathogenic bacteria and airways inflammation in severe asthma.

Long-term clinical outcomes of aspirin-exacerbated respiratory disease: Real-world data from an adult asthma cohort.

Aspirin-exacerbated respiratory disease (AERD) is a phenotype of severe asthma, but its disease course has not been well documented compared with that of aspirin-tolerant asthma (ATA). This study aimed to investigate the long-term clinical outcomes between AERD and ATA. AERD patients were identified by the diagnostic code and positive bronchoprovocation test in a real-world database. Longitudinal changes in lung function, blood eosinophil/neutrophil counts, and annual numbers of severe asthma exacerbations (AEx) were compared between the AERD and the ATA groups. Within a year after baseline, two or more severe AEx events indicated severe AERD, whereas less than two AEx events indicated nonsevere AERD. Among asthmatics, 353 had AERD in which 166 and 187 patients had severe and nonsevere AERD, respectively, and 717 had ATA. AERD patients had significantly lower FEV1%, higher blood neutrophil counts, and higher sputum eosinophils (%) (all p < .05) as well as higher levels of urinary LTE4 and serum periostin, and lower levels of serum myeloperoxidase and surfactant protein D (all p < .01) than those with ATA. In a 10-year follow-up, the severe AERD group maintained lower FEV1% with more severe AEs than the nonsevere AERD group. We demonstrated that AERD patients presented poorer long-term clinical outcomes than ATA patients in real-world data analyses.

Obesity associates with increased all-cause and cardiovascular mortality in adults with asthma

BackgroundAsthma and obesity are prevalent conditions that are increasing worldwide. Asthma is characterized by airway inflammation and bronchial variability, while obesity is a complex metabolic disorder that poses significant morbidity and mortality risks. Obesity is a risk factor for asthma and a plethora of other non-communicable diseases. ObjectiveTo compare all-cause and cause-specific mortality between obese, overweight and normal weight adults with asthma in a cohort with long-term follow-up. MethodsIndividuals from a population-based adult asthma cohort recruited in Norrbotten county, Sweden, were clinically examined between 1986 and 2001 and grouped into body mass index (BMI) categories. Underlying causes of death until December 31st, 2020 were categorized as cardiovascular, respiratory, cancer and other mortality by linking cohort data to the Swedish National Board of Health and Welfare's National Cause of Death register. Hazard ratios (HR) with 95% confidence intervals (CI) for all-cause and cause-specific mortality associated with overweight and obesity were calculated via Cox proportional hazard models. ResultsIn total, 940 individuals were normal weight, 689 overweight and 328 obese while only 13 were underweight. Obesity increased the hazard for all-cause (HR 1.26, 95% CI 1.03–1.54) and cardiovascular mortality (HR 1.43, 95% CI 1.03–1.97). Obesity was not significantly associated with respiratory or cancer mortality. Overweight did not increase the hazard of all-cause or any cause-specific mortality category. ConclusionObesity, but not overweight, was significantly associated with increased hazard of all-cause and cardiovascular mortality in adults with asthma. Neither obesity nor overweight were associated with increased hazard of respiratory mortality.

Relationship between aeroallergen sensitization pattern and clinical features in adult asthmatics

BackgroundAsthma can be classified into atopic and non-atopic phenotypes. However, limited data are available on the clinical implications of these two phenotypes in real life. ObjectiveThis study aimed to examine the clinical features as well as control level and disease severity of asthmatic patients with their aeroallergen sensitivity profiles. MethodsBetween 2013 and 2020, adult asthmatic patients who had been followed up regularly at our tertiary healthcare institution for at least one year were included in the study. We collected data retrospectively using manually filled patient files. ResultsThe mean age of 382 asthmatic patients was 46.6 ± 30.0; 77.5% were women and 75.6% had at least one aeroallergen sensitivity. Polysensitized asthmatics had better asthma symptom control and milder asthma severity than monosensitized asthmatics. Asthma symptom control status was well controlled in 67.5% of the patients, and according to asthma severity, 51.3% of the patients were classified as having moderate asthma. There was a negative relation between age (OR:0.95, CI:0.92–0.98) and atopy presence. The presence of atopy was higher in moderate asthmatics than in mild asthmatics (OR:2.02, CI:1.01–4.09). Finally, there was a positive relationship between the percent predicted forced expiratory volume in first second (FEV1%) (OR:1.02, CI:1.009–1.048) and the presence of atopy. The presence of rhinitis (OR:0.44, CI:0.22–0.88) and per 1 unit increase of Tiffeneau index (FEV1/forced vital capacity) (OR:0.94, CI:0.90–0.99) had a negative association, whereas number of medication use for asthma symptoms (OR:1.68, CI:1.18–2.39) and presence of cardiovasculary disease (OR:2.64, CI:1.19–5.84) had a positive association with not well-controlled asthma symptom level. ConclusionAeroallergen sensitivity was associated with asthma severity. However, this was not the case with asthma control levels in this adult asthma cohort. Among the atopic asthmatics polysensitized asthmatics had better asthma symptom control level and milder asthma severity level.

Patient Characteristics Associated with Adequacy of Inhaler Technique in a Severe Asthma Cohort in the Bronx

To date, most studies addressing predictive characteristics of adequate inhaler technique have been in adolescents. However, there is evidence to suggest older age correlates with poor inhaler technique. This study aimed to further investigate this association and correlate other patient characteristics with adequacy of inhaler technique in an adult asthma cohort in the Bronx.

Body mass index increase: a risk factor for forced expiratory volume in 1 s decline for overweight and obese adults with asthma.

BackgroundWith increasing prevalence of overweight and obesity, it is important to study how body mass index (BMI) change may affect lung function among subjects with asthma. There are few prospective studies on this topic, especially with separate analyses of those with normal and high BMI. The aim of the present study was to prospectively study the association between annual BMI change and annual lung function decline, separately among those with normal initial BMI and overweight/obesity, in an adult asthma cohort.MethodsA population-based adult asthma cohort was examined at study entry between 1986 and 2001 and at follow-up between 2012 and 2014 (n=945). Annual BMI change was analysed in association with annual decline in forced expiratory volume in 1 s (FEV1), forced vital capacity (FVC) and FEV1/FVC separately in those with normal weight (BMI 18.5–24.9) and overweight/obese subjects (BMI ≥25) at study entry. Regression models were used to adjust for sex, age, smoking, inhaled corticosteroids use and occupational exposure to gas, dust or fumes.ResultsOverweight/obese subjects had lower FEV1 and FVC but slower annual FEV1 and FVC decline compared to those with normal weight. After adjustment through regression modelling, the association between BMI change with FEV1 and FVC decline remained significant for both BMI groups, but with stronger associations among the overweight/obese (FEV1 B[Overweight/obese]=−25 mL versus B[normal weight]=−15 mL). However, when including only those with BMI increase during follow-up, the associations remained significant among those with overweight/obesity, but not in the normal-weight group. No associations were seen for FEV1/FVC.ConclusionsBMI increase is associated with faster FEV1 and FVC decline among overweight and obese adults with asthma in comparison with their normal-weight counterparts.

Association Between Clinical Burden and Blood Eosinophil Counts in Asthma: Findings From a Korean Adult Asthma Cohort.

BackgroundSome reports have suggested that the clinical and economic burdens of asthma are associated with blood eosinophil levels. The association between clinical burden and blood eosinophil counts were evaluated in a Korean adult asthma cohort.MethodsClinical information including blood eosinophil counts that were not affected by systemic corticosteroids were extracted from the Cohort for Reality and Evolution of Adult Asthma in Korea database. Clinical burden was defined as 1) asthma control status, 2) medication demand and 3) acute exacerbation (AE) events during 1 consecutive year after enrollment. All patients were divided into atopic and non-atopic asthmatics. The associations between asthma outcomes and the blood eosinophil count were evaluated.ResultsIn total, 302 patients (124 atopic and 178 non-atopic asthmatics) were enrolled. In all asthmatics, the risk of severe AE was higher in patients with blood eosinophil levels < 100 cells/µL than in patients with levels ≥ 100 cells/µL (odds ratio [OR], 5.406; 95% confidence interval [CI], 1.266–23.078; adjusted P = 0.023). Among atopic asthmatics, the risk of moderate AE was higher in patients with blood eosinophil levels ≥ 300 cells/µL than in patients with levels < 300 cells/µL (OR, 3.558; 95% CI, 1.083–11.686; adjusted P = 0.036). Among non-atopic asthmatics, the risk of medication of Global Initiative for Asthma (GINA) steps 4 or 5 was higher in patients with high blood eosinophil levels than in patients with low blood eosinophil levels at cutoffs of 100, 200, 300, 400, and 500 cells/µL.ConclusionThe baseline blood eosinophil count may predict the future clinical burden of asthma.

Remission and Changes in Severity Over 30 Years in an Adult Asthma Cohort

Long-term follow-up studies of adults with well-characterized asthma are sparse. We aimed to examine long-term remission and change in disease severity over 30 years in adults with asthma. A total of 125 individuals diagnosed with asthma between 1974 and 1990 at a Danish respiratory and allergy clinic, based on history and objective assessments, were included. At follow-up (2017-2019), participants completed questionnaires and had spirometry, bronchodilator reversibility, airway responsiveness, and blood biomarkers measured. Based on these assessments, participants were classified as having either active asthma, clinical remission (no symptoms or prescribed asthma medication within the last year), or complete remission (fractional exhaled nitric oxide <50 parts per billion, no bronchodilator reversibility, no airway hyperresponsiveness, and no airflow limitation). Changes in severity were determined according to Global Initiative for Asthma guidelines based on symptom control and currently prescribed medication. At follow-up, 25% (n= 31) and 15% (n= 19), respectively, had clinical and complete remission. Our analyses showed that a longer duration of symptoms before the initial assessment (odds ratio, 0.86; 95% confidence interval, 0.75-0.98) was associated with a lower chance of asthma remission. At follow-up, 30% had well-controlled asthma compared with none at baseline. Female sex, previous severe exacerbation(s), and older age at baseline were associated with uncontrolled asthma at follow-up. Blood-eosinophil count (≥0.3× 109/L) and prescribed inhaled corticosteroid (ICS) at baseline were associated with being prescribed medium/high-dose ICS at follow-up. Despite 30 years of follow-up, asthma rarely remits in adults, especially in individuals with longer duration and presumably more severe disease. Initial signs of pronounced disease activity were associated with uncontrolled asthma at follow-up.

FEV1 decline in relation to blood eosinophils and neutrophils in a population-based asthma cohort

BackgroundThe relationship between lung function decline and eosinophils and neutrophils has important therapeutic implications among asthmatics, but it has rarely been studied in large cohort studies. ObjectiveThe aim is to study the relationship between blood eosinophils and neutrophils and FEV1 decline in a long-term follow-up of a population-based adult asthma cohort. MethodsIn 2012–2014, an adult asthma cohort was invited to a follow-up including spirometry, blood sampling, and structured interviews, and n = 892 participated (55% women, mean age 59 y, 32–92 y). Blood eosinophils, neutrophils and FEV 1 decline were analyzed both as continuous variables and divided into categories with different cut-offs. Regression models adjusted for smoking, exposure to vapors, gas, dust, or fumes (VGDF), use of inhaled and oral corticosteroids, and other possible confounders were utilized to analyze the relationship between eosinophils and neutrophils at follow-up and FEV1 decline. ResultsThe mean follow-up time was 18 years, and the mean FEV 1 decline was 27 ml/year. The annual FEV1 decline was related to higher levels of both blood eosinophils and neutrophils at follow-up, but only the association with eosinophils remained when adjusted for confounders. Further, the association between FEV1 decline and eosinophils was stronger among those using ICS. With EOS <0.3 × 109/L as reference, a more rapid decline in FEV1 was independently related to EOS ≥0.4 × 109/L in adjusted analyses. Conclusions and clinical relevanceBesides emphasizing the importance of smoking cessation and reduction of other harmful exposures, our real-world results indicate that there is an independent relationship between blood eosinophils and FEV1 decline among adults with asthma.

Uncontrolled asthma occurs in all GINA treatment steps and is associated with worse physical health – a report from the OLIN adult asthma cohort

Objective: To study asthma exacerbations, healthcare utilization and health status among subjects with asthma with different treatment regimens and levels of asthma control.Methods: In 2012–2014, n = 1425 adults from a population-based asthma cohort within the OLIN studies (Obstructive Lung disease in Northern Sweden) were invited to a follow-up including spirometry and a structured interview, n = 1006 participated. Asthma Control Test (ACT) was used to detect uncontrolled asthma, and physical and mental dimensions of health were measured with SF-8. Pharmacological treatment use was classified by Global Initiative for Asthma treatment steps. Out of n = 830 with current asthma, n = 714 answered ACT (57% women, 32–92 years) and were included in the study.Results: Uncontrolled asthma increased per treatment step (no treatment 9.9%, treatment step 1–3 24.1%, and treatment steps 4–5 39.9%, p < 0.001). A higher proportion of subjects with uncontrolled asthma reported exacerbations, healthcare utilization, and worse health status than those with controlled asthma. The proportion of subjects reporting exacerbations, healthcare visits, emergency room visits and regular follow-up visits increased per treatment step. Worse health was associated with uncontrolled asthma, but not with the level of treatment. A higher proportion of women than men reported exacerbations, any healthcare visits, and lower health. Regular follow-up visits to a physician were uncommon (women 21.2% vs. men 14.6%, p = 0.022).Conclusions: Uncontrolled asthma is common in all treatment steps, and is associated with worse health status. However, health status did not differ by treatment steps. Identifying subjects with uncontrolled asthma regardless of treatment regimens should be a priority, thus follow-up visits are important.

Risk Factors for Acute Exacerbations in Elderly Asthma: What Makes Asthma in Older Adults Distinctive?

PurposeAsthma in the elderly (EA; ≥ 65 years of age) is increasing, adding a heavy socioeconomic burden to the healthcare system. However, little is known about risk factors associated with acute exacerbations in EA patients. The objective of this study was to investigate risk factors for acute exacerbation in EA compared to non-elderly asthma (NEA).MethodsWe combined data from 3 adult asthma cohorts under a unified protocol and database. Asthmatic patients with regular follow-up during a 1-year period were selected from the cohorts to identify the risk factors predicting acute exacerbations in EA compared to NEA.ResultsWe selected a total of 1,086 patients from the merged cohort. During the observation period, 503 and 583 patients were assigned to the EA and NEA groups, respectively. The exacerbation rate was 31.0% in the EA and 33.2% in the NEA group. Multivariate logistic regression analysis revealed fixed airway obstruction, chronic rhinosinusitis (CRS), and male sex as independent risk factors for exacerbation in the EA group. In the NEA group, exacerbation increased along with an increase in eosinophil count. Bayesian analysis of the interactions among clinical factors revealed that forced expiratory volume in 1 second/forced vital capacity was directly related to exacerbation in the EA group, and eosinophil count was related to exacerbation in the NEA group.ConclusionsWe suggest that fixed airway obstruction and CRS as the important clinical factors predicting acute exacerbations in EA, whereas in NEA, eosinophil count was the strong predictor of exacerbation.

Longitudinal analysis to better characterize Asthma-COPD overlap syndrome: Findings from an adult asthma cohort in Korea (COREA).

Asthma-chronic obstructive pulmonary disease (COPD) overlap syndrome (ACOS), which has received much attention, has not been unanimously defined. In this study, we tried to demonstrate that longitudinally defined ACOS is more useful in the real world than blending patients with asthma and COPD. The study patients had undergone two consecutive pulmonary function tests measured at least 3months apart (n=1889). We selected the patients who had positive bronchodilator response or methacholine provocation tests (n=959). Next, we defined ACOS as a patient with a persistent airflow obstruction [forced expiratory volume in 1second (FEV1)/forced vital capacity <0.7] that was identified twice consecutively by an interval of at least 3months (n=228). The proportions of patients who were older, male and smokers were significantly higher, and baseline lung function was lower in patients with ACOS. In the longitudinal analysis, the mean change in lung function was high, and a greater decline in FEV1 was observed in patients with ACOS. In addition, we compared ACOS and severe asthma, and we also performed a cluster analysis and compared the results with our definition of ACOS. According to our definition, ACOS is an independent subtype with distinctive characteristics. Finally, a genome-wide association study (GWAS) was performed to identify genetic variations associated with ACOS, but no significant single nucleotide polymorphisms were identified. Our findings suggest that ACOS should be defined longitudinally and considered as an independent subgroup distinguished by inherited environmental factors rather than as a genetically distinct independent group.

Sex-Specific Asthma Phenotypes, Inflammatory Patterns, and Asthma Control in a Cluster Analysis

Asthma is a heterogeneous disease with complex mechanisms and involves many risk factors and invivo cellular molecules. It is notable that sex differences may have a potential effect on asthma phenotype. To identify sex-specific phenotypes and health outcomes of asthma. We conducted the Taiwanese Adult Asthma Cohorts study to enroll female (n= 421) and male (n= 299) adult patients with stable asthma. Eight variables were selected by a factor analysis. We further performed a 2-step sensitivity cluster analysis to classify asthma clusters. The risks of asthma-related outcomes among the clusters were assessed using simple logistic regressions. Three different clusters were identified in males and females. In the female clusters, atopy/eosinophil-predominant (cluster 2), and obesity/neutrophil-predominant pattern (cluster 3) had more than a 2-fold risk of asthma exacerbations (odds ratio, 2.51; 95% CI, 1.12-5.59 and odds ratio, 2.22; 95% CI, 1.01-4.93). In the male clusters, current smoker/neutrophilic atopic cluster (cluster 5) and ex-smoker/eosinophil-predominant or mixed inflammatory pattern (cluster 6) also had a higher risk of asthma exacerbations. This study identified heterogeneous characteristics between sexes. In females, the analysis showed atopy with eosinophil-predominant and obese with neutrophil-predominant inflammation. Two distinct asthma phenotypes were found in current and ex-smokers in males. Understanding asthma phenotypes and explaining the potentially biological pathways have become important.

Chronic airway obstruction in a population-based adult asthma cohort: Prevalence, incidence and prognostic factors.

Asthma and COPD may overlap (ACO) but information about incidence and risk factors are lacking. This study aimed to estimate prevalence, incidence and risk factors of chronic airway obstruction (CAO) in a population-based adult asthma cohort. During 1986-2001 a large population-based asthma cohort was identified (n = 2055, 19-72y). Subsamples have participated in clinical follow-ups during the subsequent years. The entire cohort was invited to a clinical follow-up including interview, spirometry, and blood sampling in 2012-2014 when n = 983 subjects performed adequate spirometry. CAO was defined as post-bronchodilator FEV1/FVC<0.7. At study entry, asthmatics with prevalent CAO (11.4%) reported more respiratory symptoms, asthma medication use, and ischemic heart disease than asthmatics without CAO (asthma only). Subjects who developed CAO during follow-up (17.6%; incidence rate of 16/1000/year) had a more rapid FEV1 decline and higher levels of neutrophils than asthma only. Smoking, older age and male sex were independently associated with increased risk for both prevalent and incident CAO, while obesity had a protective effect. In this prospective adult asthma cohort, the majority did not develop CAO. Smoking, older age and male sex were risk factors for prevalent and incident CAO, similar to risk factors described for COPD in the general population.

Type 2 Biomarkers and Prediction of Future Exacerbations and Lung Function Decline in Adult Asthma

Type 2 biomarkers that predict both likelihood of future severe exacerbations and response to mAb therapy in asthma would be useful clinically in identifying patients both at greater risk of hospitalization and most likely to benefit from mAb therapy. To describe the association between type 2 biomarkers, blood eosinophils, fractional exhaled nitric oxide (Feno), serum periostin, and serum IgE, and time to severe exacerbation in a broad asthma population. Participants from 2 adult asthma cohorts with baseline measurements of blood eosinophils, Feno, serum periostin, and serum IgE were reviewed after at least 12 months to obtain an exacerbation history, corroborated with general practitioner and hospital medical records. The association between baseline type 2 biomarkers and time to exacerbation was described by Cox proportional hazard ratios (HRs) using multivariate models. A total of 212 participants were followed for a median (range) 3.8 (1.1-5.3) years; 67 of 212 (32%) had at least 1 severe exacerbation. The HRs (95% CI) of baseline type 2 biomarkers and time to exacerbation were as follows: blood eosinophils per 0.1× 109/L increase, 0.89 (0.76-1.05), P= .17; log Feno per 0.693 increase, 0.65 (0.52-0.81), P < .001; log serum periostin per 0.693 increase, 0.62 (0.35-1.09), P= .10; log serum IgE per 0.693 increase, 0.89 (0.80-1.00), P= .05. The positive association between type 2 biomarkers and risk of severe exacerbations in populations with severe refractory asthma does not extend to mild and moderate asthma. Non-type 2 asthma may represent a phenotype associated with an increased risk of severe exacerbations in a broad asthma population.

High Prevalence of Asthma in Elderly Women: Findings From a Korean National Health Database and Adult Asthma Cohort.

PurposeThe prevalence and burden of asthma is increasing worldwide. In this study, we analyzed 3 different Korean national health survey datasets to determine the general features of adult asthma in Korea and to obtain basic information that would support future strategies for better management of adult asthma.MethodsThe surveys used in this study included the Korea National Health and Nutrition Examination Survey (KNHANES), Korea Community Health Survey (KCHS) and National Health Insurance Service-National Sample Cohort (NHIS-NSC). We investigated annual asthma prevalence, evaluating the rate and risk factors of asthma exacerbation by age and sex, and clinical data of 1,832 patients with asthma who were registered in the Cohort for Reality and Evolution of Adult Asthma in Korea (COREA) were analyzed to elucidate risk factors for asthma exacerbation. We also analyzed another asthma cohort and added it as replication data.ResultsIn the KNHANES database, annual asthma prevalence rates varied from 1.2% to 3.1%. In the KCHS database, overall prevalence increased, with significant regional differences (1.6%–2.1%). The NHIS-NSC indicated a gradual increase in annual asthma prevalence from 4.5% to 6.2%. Interestingly, all 3 surveys indicated the highest prevalence of asthma among elderly women. In addition, elderly women with asthma had a significantly higher risk of asthma exacerbation (odds ratio [OR], 1.87; 95% confidence interval [CI], 1.19–2.93; P=0.006). Approximately 11% of patients were classified as having severe asthma. An asthma cohort analysis identified female sex, low baseline pulmonary function, longer treatment duration, high variability in pulmonary function and significant changes in Asthma Control Test scores as risk factors for asthma exacerbation.ConclusionsThe prevalence of asthma in Korea is consistently high among elderly and female populations. These results should lay the foundation for strategies for effective asthma prevention and management; elderly female patients with asthma should receive particular attention.

A population-based cohort of adults with asthma: mortality and participation in a long-term follow-up

ABSTRACT Background and objective: Asthma is a major public health concern. The aim of this study was to characterize a large population-based cohort of adults with asthma, and to study factors associated with all-cause mortality and non-participation in a long-term follow-up. Design: Random and stratified samples from five population-based cohorts were clinically examined during 1986–2001, and all subjects with asthma were included in the study (n = 2055, age 19–72 years, 55% women). Independent associations between different risk factors and (i) mortality and (ii) non-participation in a clinical follow-up in 2012–2014 were estimated. Results: In 1986–2001, 95% reported any wheeze and/or attacks of shortness of breath in the past 12 months, and/or asthma medication use. Over the up to 28 years of follow-up time, the cumulative mortality was 22.7%. Male gender, current smoking, and lower forced expiratory volume in 1 sec of predicted (FEV1% of predicted) were independent risk factors for mortality, while obesity was associated with non-participation in the follow-up. Older ages, ischemic heart disease, and low socioeconomic status were associated with both mortality and non-participation. Conclusions: The risk factors associated with mortality in this adult population-based asthma cohort were similar to those commonly identified in general population samples, i.e. male gender, current smoking, and lower FEV1% of predicted, while obesity was associated with non-participation in a long-term follow-up. Ischemic heart disease, low socioeconomic status, and older ages were associated with both mortality and non-participation.

Clinical and inflammatory characteristics of the European U-BIOPRED adult severe asthma cohort.

U-BIOPRED is a European Union consortium of 20 academic institutions, 11 pharmaceutical companies and six patient organisations with the objective of improving the understanding of asthma disease mechanisms using a systems biology approach.This cross-sectional assessment of adults with severe asthma, mild/moderate asthma and healthy controls from 11 European countries consisted of analyses of patient-reported outcomes, lung function, blood and airway inflammatory measurements.Patients with severe asthma (nonsmokers, n=311; smokers/ex-smokers, n=110) had more symptoms and exacerbations compared to patients with mild/moderate disease (n=88) (2.5 exacerbations versus 0.4 in the preceding 12 months; p<0.001), with worse quality of life, and higher levels of anxiety and depression. They also had a higher incidence of nasal polyps and gastro-oesophageal reflux with lower lung function. Sputum eosinophil count was higher in severe asthma compared to mild/moderate asthma (median count 2.99% versus 1.05%; p=0.004) despite treatment with higher doses of inhaled and/or oral corticosteroids.Consistent with other severe asthma cohorts, U-BIOPRED is characterised by poor symptom control, increased comorbidity and airway inflammation, despite high levels of treatment. It is well suited to identify asthma phenotypes using the array of "omic" datasets that are at the core of this systems medicine approach.

Short-term reproducibility of the inflammatory phenotype in different subgroups of adult asthma cohort.

Inflammatory phenotype classification using induced sputum appears attractive as it can be applied to inflammation-based management of the patients with asthma. The aim of the study was to determine the reproducibility of inflammatory phenotype over time in patients with asthma. In 66 adults asthma was categorized as steroid-naïve (SN, n = 17), mild to moderate (MMA, n = 33), and refractory treated with oral corticosteroids (RA, n = 16). Clinical assessment, skin prick testing, spirometry, and two sputum inductions in 4–6-week interval were done. Inflammatory phenotypes were classified as eosinophilic (EA), consisting of eosinophilic and mixed granulocytic phenotypes, and noneosinophilic (NEA) consisting of paucigranulocytic and neutrophilic phenotypes. During study asthma treatment remained constant. In SN group 25% of patients changed phenotype from EA to NEA and 44% changed phenotype from NEA to EA. In MMA group 26% of patients changed phenotype from EA to NEA and 50% changed phenotype from NEA to EA. In 29% of RA patients inflammatory phenotype changed from EA to NEA and in 22% it changed from NEA to EA. Inflammatory classification, using induced sputum, is not fully reproducible in adults with asthma in short-term evaluation. EA seems to be more stable phenotype across all subgroups whereas NEA remained stable only in RA group.