The current status of asthma in Korea

A genome-wide association study implicates the pleiotropic effect of NMUR2 on asthma and COPD

Asthma and chronic obstructive pulmonary disease (COPD) are two distinct diseases that are associated with chronic inflammation. They share common features in terms of their advanced stages and genetic factors. This study aimed to identify novel genes underlying both asthma and COPD using genome-wide association study (GWAS) to differentiate between the two diseases. We performed a GWAS of asthma and COPD in 7828 Koreans from three hospitals. In addition, we investigated genetic correlations. The UK Biobank dataset was used for the replication studies. We found that rs2961757, located near neuromedin U receptor 2 (NMUR2) on chromosome 5, was genome-wide significant ([Formula: see text] = 0.44, P-value_Asthma-COPD = 3.41 × 10^-8), and significant results were replicated with the UK Biobank data ([Formula: see text] = 0.04, P-value_Asthma-COPD = 0.0431). A positive genetic correlation was observed between asthma and COPD (39.8% in the Korean dataset and 49.8% in the UK Biobank dataset). In this study, 40-45% of the genetic effects were common to asthma and COPD. Moreover, NMUR2 increases the risk of asthma development and suppresses COPD development. This indicates that NMUR2 allows for better differentiation of both diseases, which can facilitate tailored medical therapy.

Risks of infection, hospital and ICU admission, and death from COVID-19 in people with asthma: systematic review and meta-analyses

OBJECTIVES

To determine if and to what degree asthma may predispose to worse COVID-19 outcomes in order to inform treatment and prevention decisions, including shielding and vaccine prioritisation.

DESIGN

Systematic review and meta-analysis.

SETTING

Electronic databases were searched (October 2020) for clinical studies reporting at least one of the following stratified by asthma status: risk of infection with SARS-CoV-2; hospitalisation, intensive care unit (ICU) admission or mortality with COVID-19.

PARTICIPANTS

Adults and children who tested positive for or were suspected to have COVID-19.

MAIN OUTCOME MEASURES

Main outcome measures were the following stratified by asthma status: risk of infection with SARS-CoV-2; hospitalisation, ICU admission or mortality with COVID-19. We pooled odds ratios (ORs) and presented these with 95% confidence intervals (CI). Certainty was assessed using GRADE (Grading of Recommendations, Assessment, Development and Evaluations).

RESULTS

30 (n=112 420) studies were included (12 judged high quality, 15 medium, 3 low). Few provided indication of asthma severity. Point estimates indicated reduced risks in people with asthma for all outcomes, but in all cases the evidence was judged to be of very low certainty and 95% CIs all included no difference and the possibility of increased risk (death: OR 0.90, 95% CI 0.72 to 1.13, I²=58%; hospitalisation: OR 0.95, 95% CI 0.71 to 1.26; ICU admission: OR 0.96, 95% CI 0.75 to 1.24). Findings on hospitalisation are also limited by substantial unexplained statistical heterogeneity. Within people with asthma, allergic asthma was associated with less COVID-19 risk and concurrent chronic obstructive pulmonary disease was associated with increased risk. In some studies, corticosteroids were associated with increased risk, but this may reflect increased risk in people with more severe asthma.

CONCLUSIONS

Though absence of evidence of a clear association between asthma and worse outcomes from COVID-19 should not be interpreted as evidence of absence, the data reviewed indicate that risks from COVID-19 in people with asthma, as a whole, may be less than originally anticipated.

Additive effects of coexisting respiratory comorbidities on overall or respiratory mortality in patients with asthma: a national cohort study

Asthmatic patients are generally considered to have an increased risk of mortality compared with subjects without asthma. However, this issue has been less evaluated using nationally representative data. Moreover, it is unclear whether respiratory comorbidities other than chronic obstructive pulmonary disease (COPD) are associated with increased mortality in asthmatic patients compared with subjects without. Using a nationally representative sample database, we performed a retrospective cohort study of patients with asthma and age-sex-matched control cohort. We estimated the hazard ratio (HR) and stratified the asthma cohort based on respiratory comorbidities. During a median 8.9-year follow-up, the overall mortality rate was higher in the asthma cohort than in the control cohort (p < 0.001). The hazard ratio (HR) for overall mortality in the asthma cohort compared with the control cohort was 1.13. The effects of asthma on overall mortality were more evident in males, patients under medical aid, and subjects with COPD. Respiratory comorbidities were significantly associated with increased risk of overall mortality in asthmatic patients compared with controls (adjusted HRs; 1.48 for COPD, 1.40 for bronchiectasis, 4.08 for lung cancer, and 1.59 for pneumonia). While asthma and lung cancer showed an additive effect only on overall mortality, asthma and other respiratory comorbidities (COPD, pneumonia, and bronchiectasis) had additive effects only on respiratory mortality. Patients with asthma had a higher overall mortality rate compared with subjects without asthma. Respiratory comorbidities showed an additive effect on overall or respiratory mortality in patients with asthma.

Pragmatic Randomized Controlled Trial for Stepping Down Asthma Controller Treatment in Patients Controlled with Low-Dose Inhaled Corticosteroid and Long-Acting β2-Agonist: Step-Down of Intervention and Grade in Moderate Asthma Study

BACKGROUND

Current asthma guidelines recommend stepping down controller treatment when the condition is well-controlled for a certain time. However, the optimal step-down strategy for well-controlled patients receiving a low-dose inhaled corticosteroid (ICS) with a long-acting β₂-agonist (LABA) remains unclear.

OBJECTIVE

This study was a randomized, open-label, three-arm, parallel pragmatic trial comparing two kinds of step-down approaches for maintaining treatment.

METHODS

Adults with asthma who were aged 18 years or older, and who had been stable with low-dose ICS/LABA for at least 3 months, were enrolled. Subjects (n = 225) were randomly allocated into one of three groups (maintaining low-dose ICS/LABA [G1], discontinuing LABA [G2], and reducing ICS/LABA to once daily [G3]), and were observed for 6 months. The primary end point was a change in Asthma Control Test (ACT) scores between randomization and the final 6-month follow-up.

RESULTS

The change in ACT was analyzed in the per-protocol population; noninferiority was not demonstrated in either step-down group compared with the maintenance group (95% confidence interval of the difference, G2 vs G1 = -1.40-0.55; G3 vs G1 = -1.19-0.77). Although over 90% of patients were fine, higher rates of treatment failure were observed in step-down groups (G1: 0%; G2: 9.46%; and G3: 9.09%; P = .027). There were no significant differences between step-down approaches in terms of ACT change or treatment failure.

CONCLUSIONS

Both step-down methods were not noninferior to maintenance of treatment. Step-down therapy can be attempted when patients are stable, but appropriate monitoring and supervision are necessary with precautions regarding loss of disease control.

Genome-Wide Association Study of Korean Asthmatics: A Comparison With UK Asthmatics

PURPOSE

Although genome-wide association studies (GWASs) represent the most powerful approach for identifying genes that influence asthma, to date, no studies have established genetic susceptibility to asthma in the Korean population. This study aimed to identify genetic variants associated with adult Korean asthmatics and compare them with the significant single nucleotide polymorphisms (SNPs) of UK asthmatics from the UK Biobank.

METHODS

Patients were defined as having asthma if they were diagnosed by a doctor or taking medications for asthma. Controls were defined as individuals without asthma or chronic obstructive pulmonary disease. We performed quality control, genotype imputation, GWAS, and PrediXcan analyses. In the GWAS, a P value of < 5 × 10^-8 was considered significant. We compared significant SNPs between Korean and UK patients with asthma.

RESULTS

A total of 1,386 asthmatic patients and 5,205 controls were analyzed. The SNP rs1770, located near the human leukocyte antigen (HLA)-DQB1, was the most significant SNP (P = 4.5 × 10^-10). In comparison with 24 SNPs in a GWAS of UK asthmatics, six SNPs were significant with the same odds ratio (OR) direction, including signals related to type 2 inflammation (e.g., IL1RL1, TSLP, and GATA3) and mucus plugging (e.g., MUC5AC). HLA-DQA1 showed an opposite OR direction. The HLA-DQB1 gene demonstrated significantly imputed mRNA expression in the lung tissue and whole blood.

CONCLUSIONS

The SNP rs1770 of HLA-DQB1 was the most significant in Korean asthmatics. Similarities and discrepancies were found in the genetic variants between Korean and UK asthmatics. GWAS of Korean asthmatics should be replicated and compared with those of GWAS of other ethnicities.

Assessment of Relative Asthma Risk in Populations Living Near Incineration Facilities in Seoul, Korea

While incineration is among the most commonly used technologies for waste disposal, there is ongoing public concern regarding the adverse health impact. The aim of this study is thus to use health statistics to assess the relative risk of asthma-related hospitalization for those living in close proximity to incineration facilities. We also examine differences in asthma risk related to age demographics. The spatial relationship between incineration facilities and asthma-related hospital admissions in Seoul is analyzed for the period of 2009–2011 using the Rapid Inquiry Facility (RIF) and SaTScan software. The relative risk of asthma-related hospitalization decreased with increasing distance from incinerators, but increased among those living within a 2-km radius. The relative risks of asthma-related hospitalization were 1.13 (95% confidence interval (CI): 1.10–1.17), 1.12 (95% CI: 1.08–1.17), and 1.18 (95% CI: 1.10–1.27) for all ages, those aged below 15 years, and those aged 65 years and older, respectively. This study is the first to observe an increased risk of asthma-related hospitalization in relation to a person’s distance from an incinerator in Seoul, Korea. It is clear that asthma should be considered an adverse health outcome during health impact assessments of incineration plants.

Implementation of Asthma Management Guidelines and Possible Barriers in Korea

BACKGROUND

There could be a gap between asthma management guidelines and current practice. We evaluated the awareness of and compliance with asthma management guidelines, and the internal and external barriers to compliance, for the first time in Korea.

METHODS

From March to September of 2012, 364 physicians treating asthma patients at primary, secondary, and tertiary teaching hospitals were enrolled. They completed a questionnaire on the awareness of and compliance with asthma management guidelines, and the barriers and alternatives to their implementation.

RESULTS

Of the 364 physicians, 79.1% were men and 56.9% were primary care physicians. The mean age was 40.5 ± 11.2 years. Most of them were aware of asthma management guidelines (89.3%). However, only a portion (11.0%) of them complied with the guidelines for asthma. Pulmonary function tests for diagnosis of asthma were performed by 20.1% of all physicians and 9.2% of primary care physicians, and by 9.9% of all physicians and 5.8% of primary care physicians for monitoring. Physicians stated that 'asthma monitoring' was the most difficult part of the guidelines, followed by 'environmental control and risk factors.' Only 39.6% (31.9% of the primary care physicians) prescribed an inhaled corticosteroid (ICS) as the first-line treatment for persistent asthma. The internal barriers were physician's preference for oral medications, difficulty in use even with inhaler training, and concern over ICS side effects. The external barriers were possible rejection of medical reimbursement by health insurance, refusal by the patient, cost, and a poor environment for teaching the patient how to use the inhaler. Alternatives proposed by physicians to implement asthma management guidelines were to improve medical reimbursement policies and the level of awareness of such guidelines.

CONCLUSION

Compliance with the asthma management guidelines, including ICS prescription, is low despite the awareness of the guidelines. It is necessary to develop a strategy to overcome the internal and external barriers.

Regional Variation of Hospitalization Rates for Asthma in Korea: Association with Ambient Carbon Monoxide and Health Care Supply

This study was performed to investigate the relationship between the hospitalization rate for asthma and the ambient carbon monoxide (CO) by examining regional variation of the hospitalization rates for asthma in Korea and its factors. The hospital inpatient claims for asthma were acquired from the National Health Insurance database in 2015. A multivariate linear regression was performed with the hospitalization rate for asthma as a dependent variable. The annual ambient concentration of CO showed a negative association with the hospitalization rates for asthma while that of sulfur dioxide showed a positive association. The number of primary care physicians showed a negative association with the hospitalization rates for asthma while the number of beds in hospitals with less than 300 beds showed a positive association. The negative association of the ambient concentration of CO with the hospitalization rates for asthma showed results upon further investigation.

Association between exposure to traffic-related air pollution and pediatric allergic diseases based on modeled air pollution concentrations and traffic measures in Seoul, Korea: a comparative analysis

BACKGROUND

Pediatric allergic diseases are a major public health concern, and previous studies have suggested that exposure to traffic-related air pollution (TRAP) exposure is a risk factor. These studies have typically assessed TRAP exposure using traffic measures, such as distance to major roads, or by modeling air pollutant concentrations; however inconsistent associations with pediatric allergic diseases have often been found. Using road proximity and density, we previously found an association between TRAP and atopic eczema among approximately 15,000 children living in Seoul, Korea, heavily populated and highly polluted city in which traffic is a major emission source. We aimed to conduct a parallel analysis using modeled air pollution concentrations and thus examine the consistency of the association. Specifically, we examined the associations of individual-level annual-average concentrations of NO₂, PM₁₀, and PM_2.5 with symptoms and diagnoses of three pediatric allergic diseases including asthma, allergic rhinitis, and atopic eczema.

METHODS

The study population included 14,614 children from the Seoul Atopy Friendly School Project Survey in Seoul, Korea, in 2010. To assess individual exposures to TRAP among these children, we predicted annual-average concentrations of NO₂, PM₁₀, and PM_2.5 at the children's home addresses in 2010 using universal kriging and land use regression models along with regulatory air quality monitoring data and geographic characteristics. Then, we estimated odds ratios (ORs) of the three allergic diseases for interquartile increases in air pollution concentrations after adjusting for individual risk factors in mixed effects logistic regression.

RESULTS

Symptoms and diagnoses of atopic eczema symptoms showed an association with NO₂ (OR = 1.07, 95% confidence interval = 1.02-1.13; 1.08, 1.03-1.14) and PM₁₀ (1.06, 1.01-1.12; 1.07, 1.01-1.13). ORs of PM_2.5 were positive but not statistically significant (1.01, 0.95-1.07; 1.04, 0.98-1.10). No association was found between asthma and allergic rhinitis, although PM_2.5 showed a marginal association with allergic rhinitis.

CONCLUSIONS

Our consistent findings regarding the association between TRAP and the prevalence of atopic eczema using traffic measures and surrogate air pollutants suggested the effect of TRAP on children's health. Follow-up studies should elucidate the causal link, to support subsequent policy considerations and minimize adverse health effects in children.

Increasing Prevalence and Mortality of Asthma With Age in Korea, 2002-2015: A Nationwide, Population-Based Study

Purpose

The prevalence of asthma is increasing globally as the world population increases; however, and the prevalence and mortality of asthma have not been extensively investigated. Also, the effects of severity and aging on asthma prevalence and mortality are unknown. We aimed to investigate trends of the prevalence and mortality of asthma as well as health care uses and costs over 14 years according to disease severity by using real-world data in Korea.

Methods

Using the National Health Insurance Sharing Service database, we extracted asthmatic patients having diagnosis codes of asthma and prescription records of antiasthmatic medications from 2002 to 2015 and categorized them according to asthma exacerbation and regular treatment. We defined asthma-associated death in terms of patients' prescription records within 3 months before all-cause death, then linked with the Cause of Death Statistics. The annual asthma-related health care uses and costs were analyzed.

Results

The prevalence rates of asthma (1.6% to 2.2%) and severe asthma (SA; 3.5% to 6.1% among total asthmatics) have increased steadily over the decade in Korea, where the proportion of elderly asthmatics having increased. The asthma-related health care uses and costs had increased during the study period with the highest uses/costs in SA. The asthma mortality had a steady rising trend from 16.2 to 28.0 deaths per 100,000 with the highest mortality in SA.

Conclusions

The prevalence and mortality of asthma as well as SA increases along with the burden of health care uses/costs. More active interventions, including changes in health care policies, are needed to reduce the prevalence and mortality of asthma, especially SA.

Association Between Asthma and Depression: A National Cohort Study

BACKGROUND

Patients with asthma often suffer from depression and vice versa. However, the temporal relationship between the 2 diseases has remained elusive.

OBJECTIVE

The aim of this study was to determine the bidirectional relationship between asthma and depression in adults, using national cohort samples in Korea.

METHODS

Using the national cohort from the study by the Korean Health Insurance Review and Assessment Service, patients with asthma and control participants were selected and matched by age group, sex, income group, region of residence, and medical histories. A stratified Cox proportional hazards model was used to analyze the hazard ratio (HR) of asthma with depression (study 1) and depression with asthma (study 2).

RESULTS

In study 1, the HR of depressive disorders was significantly higher in patients with asthma than in patients without asthma (HR, 1.35; 95% CI, 1.31-1.40). In study 2, the HR of asthma in patients with depression was significantly higher than that in patients without depression (HR, 1.25; 95% CI, 1.21-1.29).

CONCLUSION

A bidirectional association between asthma and depression was observed in this study.

The virtual asthma guideline e-learning program: learning effectiveness and user satisfaction

BACKGROUND/AIMS

Effective educational tools are important for increasing adherence to asthma guidelines and clinical improvement of asthma patients. We developed a computer-based interactive education program for asthma guideline named the Virtual Learning Center for Asthma Management (VLCAM). We evaluated the usefulness of program in terms of its effects on user awareness of asthma guideline and level of satisfaction.

METHODS

Physicians-in-training at tertiary hospitals in Korea were enrolled in a cross-sectional questionnaire survey. The e-learning program on asthma guideline was conducted over a 2-week period. We investigated changes in the awareness of asthma guideline using 35-item self-administered questionnaire aiming at assessing physicians' knowledge, attitude, and practice. Satisfaction with the program was scored on 4-point Likert scales.

RESULTS

A total of 158 physicians-in-training at six tertiary hospitals completed the survey. Compared with baseline, the overall awareness obtained from the scores of knowledge, attitude, and practice was improved significantly. Participants were satisfied with the VLCAM program in the following aspects: helpfulness, convenience, motivation, effectiveness, physicians' confidence, improvement of asthma management, and willingness to recommend. All items in user satisfaction questionnaires received high scores over 3 points. Moreover, the problem-based learning with a virtual patient received the highest user satisfaction among all parts of the program.

CONCLUSIONS

Our computer-based e-learning program is useful for improving awareness of asthma management. It could improve adherence to asthma guidelines and enhance the quality of asthma care.

Risk factors of asthma exacerbation based on asthma severity: a nationwide population-based observational study in South Korea

OBJECTIVES

Asthma exacerbation, associated with many risks factors, can reflect management failure. However, little is known about how risk factors are associated with exacerbation, according to asthma severity. We aimed to investigate differences in risk factors in patients with different asthma severity and evaluate whether risk factors differed between frequent exacerbators and patients with single exacerbation.

DESIGN

Nationwide population-based observational study.

SETTING

Korean National Sample Cohort database.

PARTICIPANTS

We included 22 130 adults with asthma diagnoses more than twice (ICD-10 (International Classification of Diseases, Tenth revision) codes J45 and J46) and one prescription for asthma medication from 2010 to 2011.

OUTCOME MEASURES

Asthma exacerbation was defined as having a corticosteroid (CS) burst characterised by a prescription of high-dose oral CS for ≥3 days or one systemic CS injection, hospitalisation or emergency department visit.

RESULTS

Among severities, history of CS bursts was significantly associated with exacerbation. In mild and moderate asthma, exacerbation was significantly associated with age ≥45 years, being female, gastro-oesophageal reflux disease and chronic rhinitis. High medication possession ratio (MPR≥50%), compared with low MPR (<20%) showed adjusted ORs of 0.828 (95% CI 0.707 to 0.971) and 0.362 (0.185 to 0.708) in moderate and severe asthma, respectively. In severe asthma, compared with mild asthma, only allergic rhinitis and history of hospitalisation were strongly associated with exacerbation. When comparing frequent exacerbators to patients with single exacerbation, age ≥45 years, atopic dermatitis, anxiety and history of CS burst were significant risk factors in mild and moderate asthma, whereas no risk factors were significant in severe asthma.

CONCLUSIONS

Different associations between risk factors and asthma exacerbations based on asthma severity suggest that patients with mild asthma require greater attention to their age and comorbidities, whereas those with severe asthma require greater attention to hospitalisation history and drug adherence.

Gene editing as a promising approach for respiratory diseases

Respiratory diseases, which are leading causes of mortality and morbidity in the world, are dysfunctions of the nasopharynx, the trachea, the bronchus, the lung and the pleural cavity. Symptoms of chronic respiratory diseases, such as cough, sneezing and difficulty breathing, may seriously affect the productivity, sleep quality and physical and mental well-being of patients, and patients with acute respiratory diseases may have difficulty breathing, anoxia and even life-threatening respiratory failure. Respiratory diseases are generally heterogeneous, with multifaceted causes including smoking, ageing, air pollution, infection and gene mutations. Clinically, a single pulmonary disease can exhibit more than one phenotype or coexist with multiple organ disorders. To correct abnormal function or repair injured respiratory tissues, one of the most promising techniques is to correct mutated genes by gene editing, as some gene mutations have been clearly demonstrated to be associated with genetic or heterogeneous respiratory diseases. Zinc finger nucleases (ZFN), transcription activator-like effector nucleases (TALEN) and clustered regulatory interspaced short palindromic repeats/CRISPR-associated protein 9 (CRISPR/Cas9) systems are three innovative gene editing technologies developed recently. In this short review, we have summarised the structure and operating principles of the ZFNs, TALENs and CRISPR/Cas9 systems and their preclinical and clinical applications in respiratory diseases.

Are sleep disorders associated with increased mortality in asthma patients?

BACKGROUND

South Korea has experienced problems regarding poor management of symptoms of asthma patients and remarkable increases in sleep disorders. However, few studies have investigated these issues. We examined the relationship between sleep disorders and mortality in asthma patients to suggest effective alternatives from a novel perspective.

METHODS

We used data from the National Health Insurance Service (NHIS) National Sample Cohort 2004-2013, which included medical claims filed for 186,491 patients who were newly diagnosed with asthma during the study period. We performed survival analyses using a Cox proportional hazards model with time-dependent covariates to examine the relationship between sleep disorders and mortality in asthma patients.

RESULTS

There were 5179 (2.78%) patients who died during the study period. Sleep disorders in patients previously diagnosed with asthma were associated with a higher risk of mortality (hazard ratio [HR]: 1.451, 95% confidence interval [CI]: 1.253-1.681). In addition, significant interaction was found between sleep disorders and Charlson comorbidity index.

CONCLUSIONS

Our findings suggest that an increased prevalence of sleep disorders in asthma patients increases the risk of mortality. Considering the worsening status of asthma management and the rapid growth of sleep disorders in South Korea, clinicians and health policymakers should work to develop interventions to address these issues.

Effects of Educational Interventions for Chronic Airway Disease on Primary Care

Education has been known to essential for management of chronic airway diseases. However the real benefits remain unclear. We evaluated the effectiveness of an organized educational intervention for chronic airway diseases directed at primary care physicians and patients. The intervention was a 1-month education program of three visits, during which subjects were taught about their disease, an action plan in acute exacerbation and inhaler technique. Asthma control tests (ACT) for asthma and, chronic obstructive pulmonary disease (COPD) assessment tests (CAT) for COPD subjects were compared before and after education as an index of quality of life. Educational effectiveness was also measured associated with improvement of their knowledge for chronic airway disease itself, proper use of inhaler technique, and satisfaction of the subjects and clinicians before and after education. Among the 285 participants, 60.7% (n = 173) were men and the mean age was 62.2 ± 14.7. ACT for asthma and CAT in COPD patients were significantly improved by 49.7% (n = 79) and 51.2% (n = 65) more than MCID respectively after education (P < 0.05). In all individual items, knowledge about their disease, inhaler use and satisfaction of the patients and clinicians were also improved after education (P < 0.05). This study demonstrates the well-organized education program for primary care physicians and patients is a crucial process for management of chronic airway diseases.

Korean Asthma Guideline 2014: Summary of Major Updates to the Korean Asthma Guideline 2014

Asthma is a prevalent and serious health problem in Korea. Recently, the Korean Asthma Guideline has been updated by The Korean Academy of Tuberculosis and Respiratory Diseases (KATRD) in an effort to improve the clinical management of asthma. This guideline focuses on adult patients with asthma and aims to deliver up to date scientific evidence and recommendations to general physicians for the management of asthma. For this purpose, this guideline was updated following systematic review and meta-analysis of recent studies and adapting some points of international guidelines (Global Initiative for Asthma [GINA] report 2014, National Asthma Education and Prevention Program [NAEPP] 2007, British Thoracic Society [BTS/SIGN] asthma guideline 2012, and Canadian asthma guideline 2012). Updated issues include recommendations derived using the population, intervention, comparison, and outcomes (PICO) model, which produced 20 clinical questions on the management of asthma. It also covers a new definition of asthma, the importance of confirming various airflow limitations with spirometry, the epidemiology and the diagnostic flow of asthma in Korea, the importance and evidence for inhaled corticosteroids (ICS) and ICS/formoterol as a single maintenance and acute therapy in the stepwise management of asthma, assessment of severity of asthma and management of exacerbation, and an action plan to cope with exacerbation. This guideline includes clinical assessments, and treatment of asthma–chronic obstructive pulmonary disease overlap syndrome, management of asthma in specific conditions including severe asthma, elderly asthma, cough variant asthma, exercise-induced bronchial contraction, etc. The revised Korean Asthma Guideline is expected to be a useful resource in the management of asthma.

Does urban land-use increase risk of asthma symptoms?

BACKGROUND

Global urbanization is increasing rapidly, especially in Asian countries. The health impacts of this unprecedented rate of urbanization are not well understood. Prevalence of asthma is also increasing, especially in cities.

METHODS

We explored the effects of urbanicity, based on urban land-use and traffic-related air pollutants (NO2, PM10), on asthma symptoms and diagnosis at a nationally representative level, using individual-level data from the 2008-2010 Community Health Survey data in Korea. We applied logistic regression, adjusting for sex, age, education, smoking status, and household income. To investigate whether different levels of urban intensity (i.e., degree of urbanization) affected the association, we stratified analysis by urban intensity for the subject's residential district: high (≥30% urban), medium (10-30%), and low intensity (<10%).

RESULTS

Increased urban land-use was significantly associated with increased risk of asthma symptoms and diagnosis. A 10% increase of urban land-use of a subject's residential district was associated with an odds ratio (OR) of 1.03 (95% CI: 1.02, 1.04) for self-reported physician-diagnosed asthma. However, increased urbanicity is associated with higher risk of asthma in areas with a baseline of low urbanicity, but not in areas with a baseline of high urbanicity. Significant positive associations were also observed for air pollution (PM10 and NO2) with asthma symptoms and diagnosis.

CONCLUSIONS

Our findings suggest that increases in urbanicity or air pollution are associated with increased risk of asthma, and that the level of urban intensity affected the associations.

The Effect of Asthma Clinical Guideline for Adults on Inhaled Corticosteroids PrescriptionTrend: A Quasi-Experimental Study

In order to increase inhaled corticosteroid (ICS) use and to reduce hospitalization, emergency department visits and ultimately the economic burden of asthma, "Korean Asthma Management Guideline for Adults 2007" was developed. To assess the guideline effects on physician's ICS prescription for asthma, we conducted segmented regression and multilevel logistic regression using National Health Insurance claims database of outpatient visits from 2003 to 2010. We set each quarter of a year as a time unit and compared ICS prescription between before and after guideline dissemination. A total of 624,309 quarterly visits for asthma was observed. The ICS prescription rate before and after guideline dissemination was 13.3% and 16.4% respectively (P < 0.001). In the segmented regression, there was no significant guideline effect on overall ICS prescription rate. In multilevel logistic regression analyses, the effect of guideline on overall ICS prescription was not significant (odds ratio, 1.03; 95% CI, 1.00-1.06). In subgroup analysis, ICS prescription increased in secondary care hospitals (odds ratio, 1.15; 95% CI, 1.02-1.30) and in general hospitals (odds ratio, 1.10; 95% CI, 1.04-1.16). However, in primary clinics, which covered 81.7% of asthma cases, there was no significant change (odds ratio, 0.98; 95% CI, 0.94-1.02). From the in-depth interview, we could identify that the reimbursement criteria of the Health Insurance Review and Assessment Service and patient's preference for oral drug were barriers for the ICS prescription. The domestic asthma clinical guideline have no significant effect on ICS prescription, especially in primary clinics.

Urban microbiomes and urban ecology: how do microbes in the built environment affect human sustainability in cities?

Humans increasingly occupy cities. Globally, about 50% of the total human population lives in urban environments, and in spite of some trends for deurbanization, the transition from rural to urban life is expected to accelerate in the future, especially in developing nations and regions. The Republic of Korea, for example, has witnessed a dramatic rise in its urban population, which now accounts for nearly 90% of all residents; the increase from about 29% in 1955 has been attributed to multiple factors, but has clearly been driven by extraordinary growth in the gross domestic product accompanying industrialization. While industrialization and urbanization have unarguably led to major improvements in quality of life indices in Korea and elsewhere, numerous serious problems have also been acknowledged, including concerns about resource availability, water quality, amplification of global warming and new threats to health. Questions about sustainability have therefore led Koreans and others to consider deurbanization as a management policy. Whether this offers any realistic prospects for a sustainable future remains to be seen. In the interim, it has become increasingly clear that built environments are no less complex than natural environments, and that they depend on a variety of internal and external connections involving microbes and the processes for which microbes are responsible. I provide here a definition of the urban microbiome, and through examples indicate its centrality to human function and wellbeing in urban systems. I also identify important knowledge gaps and unanswered questions about urban microbiomes that must be addressed to develop a robust, predictive and general understanding of urban biology and ecology that can be used to inform policy-making for sustainable systems.

Physician-prescribed Asthma Treatment Regimen does not differ Between Smoking and Non-smoking Patients With Asthma in Seoul and Gyunggi province of Korea

Purpose

Smoking has detrimental effects on asthma symptom control and response to treatment and is prevalent among asthma patients in South Korea. The aim of this study is to determine the prevalence of smoking among asthma patients in South Korea and to compare the medication regimens of asthma patients who do and do not smoke.

Methods

A cross-sectional survey was conducted from August 2010 to January 2011. Participating physicians (N=25) recorded demographic and clinical data on all asthma patients presenting during the study period (N=2,032), and then recruited a subset of patients (N=500) for the survey such that half were self-reported current smokers. Recruited patients were between the ages of 18 and 60.

Results

Among presenting asthma patients, 17.3% were current smokers, 19.2% were former smokers, and 63.5% had never smoked. Within the analyzable study population (N=471), 212 patients reported smoking currently, 79 smoking formerly, and 180 never smoking. Among current and former smokers, 79.7% and 81.0%, respectively, were men, while women represented 80.5% of patients who had never smoked. Agreement was strong between physician-determined smoking status and patient-reported smoking status (κ=0.82; P<0.001). However, asthma medication regimens examined according to GINA treatment steps did not differ by smoking status. In addition, mean quality of life scores and level of asthma control did not differ by smoking status.

Conclusions

In South Korea, physicians are well aware of the smoking status of their patients. However, smoking status did not affect the prescribed medication regimens of this population of asthma patients.

Effects of Air Pollution on Asthma Hospitalization Rates in Different Age Groups in Metropolitan Cities of Korea

Many studies have shown associations between air pollution and asthma admissions in Korea, but have not reported whether these effects differ by age classification. The purpose of this study was to determine whether air pollution effects on asthmatic hospital admissions are different by three age groups (years): children (less than 15), adults (15-64; reference group), and the elderly (over 65). Daily time-series data from seven metropolitan cities in South Korea were analyzed in two stages. In the first stage, relative asthma morbidity rates associated with air pollution were estimated for each city and age group, using semi-parametric log-linear regression. In the second stage, estimates from all seven cities were combined by age group using Bayesian hierarchical modeling. The effects of exposure to particulate matter <10 micrometers in aerodynamic diameter (PM₁₀), carbon monoxide (CO) and nitrogen dioxide (NO₂) varied significantly by age groups. Using adults as the referent, the relative rate (RR) of asthma admissions with 10μg/m³ increase of PM10 is 1.5% (95%CI: 0.1-2.8%) lower for children, and 1.3% (95% CI: 0.7-1.9%) higher for the elderly; RR with 1ppm increase of CO is 1.9% (95% CI: 0.3-3.8%) lower for children; RR with 1ppb increase of NO₂(1ppb) is 0.5% (95% CI: 0.3-0.7%) higher for the elderly. No significant age group difference in relative rate was found for ozone or sulfur dioxide.

Allergic diseases in preschoolers are associated with psychological and behavioural problems

Purpose

The aim of the present study was to investigate the relationship between three major allergic diseases, asthma, allergic rhinitis (AR), and atopic dermatitis (AD), and psychological and behavioural problems in preschoolers based on a community survey.

Methods

A cross-sectional survey was conducted using a modified International Study of Asthma and Allergies in Childhood questionnaire to determine the prevalence of symptoms and diagnosed allergic diseases, and a Korean version of the Child Behaviour Checklist to assess internalizing, externalizing, and sleep problems among 780 preschoolers. Five-hundred and seventy-five preschoolers with valid data were included in this study.

Results

The prevalence of lifetime diagnosis and treatment in the past 12 months was 8.7% and 4.4% for asthma, 24.4% and 19.2% for AR, and 35.1% and 16.6% for AD, respectively. Scores for internalizing and sleep problems were significantly higher in those diagnosed with AR. Preschoolers who had been treated for AD in the past 12 months had higher attention problem and attention-deficit/hyperactivity disorder scores. Sleep problems were more severe in moderate to severe AD compared to control and mild AD groups, categorised according to SCOring index of AD. The severity of sleep problems correlated positively with the percentage of eosinophils in peripheral blood.

Conclusions

Psychological and behavioural problems differed among the three major allergic diseases, weaker association for asthma and stronger association for AR and AD. The results of this study may lead to the identification of potential underlying shared mechanisms common to allergic diseases and psychological and behavioural problems.

New insight into the assessment of asthma using xenon ventilation computed tomography

BACKGROUND

Image analyses include computed tomography (CT), magnetic resonance imaging, and xenon ventilation CT, which is new modality to evaluate pulmonary functional imaging.

OBJECTIVE

To examine the usefulness of dual-energy xenon ventilation CT in asthmatic patients.

METHODS

A total of 43 patients 18 years or older who were nonsmokers were included in the study. Xenon CT images in wash-in and wash-out phases were obtained at baseline and after inhalation of methacholine and salbutamol. The degrees of ventilation defects and xenon trappings were evaluated through visual analysis.

RESULTS

Ventilation defects and xenon trapping were significantly increased and decreased after methacholine challenge and salbutamol inhalation, respectively (P < .005). The ventilation abnormalities were not significantly related to the percentage of forced expiratory volume in 1 second (FEV1) or the ratio of FEV1 to forced vital capacity. Xenon trappings after salbutamol inhalation were negatively related to the scores of the asthma control test, wheezing, or night symptoms, with statistical significance (P < .05), whereas, FEV1 showed no significant correlation with symptom scores. Baseline FEV1 was significantly lower and dyspnea and wheezing were more severe in the non-full reversal group than in the full reversal group after salbutamol inhalation in xenon CT (P < .05). The degree of ventilation defects were positively correlated with FEV1 improvement after 3 months of treatment (P = .02).

CONCLUSION

The results of this study suggest that xenon ventilation CT can be used as a new method to assess ventilation abnormalities in asthma, and these ventilation abnormalities can be used as novel parameters that reflect the status of asthma control and symptom severity.

Immunopathogenesis of allergic asthma: more than the th2 hypothesis

Asthma is a chronic obstructive airway disease that involves inflammation of the respiratory tract. Biological contaminants in indoor air can induce innate and adaptive immune responses and inflammation, resulting in asthma pathology. Epidemiologic surveys indicate that the prevalence of asthma is higher in developed countries than in developing countries. The prevalence of asthma in Korea has increased during the last several decades. This increase may be related to changes in housing styles, which result in increased levels of indoor biological contaminants, such as house dust mite-derived allergens and bacterial products such as endotoxin. Different types of inflammation are observed in those suffering from mild-to-moderate asthma compared to those experiencing severe asthma, involving markedly different patterns of inflammatory cells and mediators. As described in this review, these inflammatory profiles are largely determined by the involvement of different T helper cell subsets, which orchestrate the recruitment and activation of inflammatory cells. It is becoming clear that T helper cells other than Th2 cells are involved in the pathogenesis of asthma; specifically, both Th1 and Th17 cells are crucial for the development of neutrophilic inflammation in the airways, which is related to corticosteroid resistance. Development of therapeutics that suppress these immune and inflammatory cells may provide useful asthma treatments in the future.

Clonorchis sinensis infection is positively associated with atopy in endemic area

BACKGROUND

Epidemiologic studies have suggested that helminth infections play a protective role against allergy; this inverse association, however, has not been consistent. Clonorchis sinensis, the liver fluke of human, is prevalent in the Far East. The association between C. sinensis infection and allergy has not yet been reported.

OBJECTIVE

We evaluated the association between clonorchiasis and atopy or allergic diseases in adults in endemic areas of clonorchiasis.

METHODS

A total of 1116 subjects (males 419, females 697; age range, 30-86; mean age=61 years) were recruited from two endemic areas of C. sinensis in Korea. Clonorchiasis was confirmed by stool examination. Allergic symptoms were evaluated with a modified ISAAC questionnaire, and atopy was defined by skin prick test for common inhalant allergens. Total serum IgE and C. sinensis-specific IgE level was measured by ELISA and methacholine bronchial provocation test was performed to evaluate airway hyperresponsiveness (AHR).

RESULTS

Clonorchiasis was positively associated with atopy [odds ratio (OR), 1.856; 95% confidence interval (CI), 1.199-2.873] and high levels of total serum IgE (OR, 1.455; 95% CI, 1.050-2.016). Higher association with clonorchiasis was shown in subjects who showed both atopy and high total serum IgE levels (OR, 2.540; 95% CI, 1.448-4.455). Clonorchiasis had no association with wheezing, AHR, asthma or allergic rhinitis.

CONCLUSION AND CLINICAL RELEVANCE

Clonorchiasis was positively associated with atopy in adults in endemic area.

Ambient air pollution and allergic diseases in children

The prevalence of allergic diseases has increased worldwide, a phenomenon that can be largely attributed to environmental effects. Among environmental factors, air pollution due to traffic is thought to be a major threat to childhood health. Residing near busy roadways is associated with increased asthma hospitalization, decreased lung function, and increased prevalence and severity of wheezing and allergic rhinitis. Recently, prospective cohort studies using more accurate measurements of individual exposure to air pollution have been conducted and have provided definitive evidence of the impact of air pollution on allergic diseases. Particulate matter and ground-level ozone are the most frequent air pollutants that cause harmful effects, and the mechanisms underlying these effects may be related to oxidative stress. The reactive oxidative species produced in response to air pollutants can overwhelm the redox system and damage the cell wall, lipids, proteins, and DNA, leading to airway inflammation and hyper-reactivity. Pollutants may also cause harmful effects via epigenetic mechanisms, which control the expression of genes without changing the DNA sequence itself. These mechanisms are likely to be a target for the prevention of allergies. Further studies are necessary to identify children at risk and understand how these mechanisms regulate gene-environment interactions. This review provides an update of the current understanding on the impact of air pollution on allergic diseases in children and facilitates the integration of issues regarding air pollution and allergies into pediatric practices, with the goal of improving pediatric health.

Economic costs for adult asthmatics according to severity and control status in Korean tertiary hospitals

OBJECTIVE

The prevalence of asthma is increasing, and asthma causes considerable socioeconomic burden worldwide. Few studies have been conducted to evaluate the risk factors associated with economic cost of asthma in Korea. This study evaluated asthma cost according to severity, control, and patient factors in Korean tertiary hospitals.

METHODS

Direct and indirect costs were assessed in physician-diagnosed adult asthmatics recruited from eight tertiary hospitals in Korea. Official direct medical costs were derived from the analysis of 1-year expenditures related to hospital care utilization and asthma medication. Nonofficial medical costs, nonmedical direct costs, and indirect costs were investigated using a questionnaire designed specifically for the study.

RESULTS

A total of 314 patients with persistent asthma were recruited. Both direct and indirect costs were significantly higher for patients with severe persistent asthma than for those with mild and moderate persistent asthma ($2214 vs. $871 and $978, p < .001; $2927 vs. $490 and $443, p < .001, respectively). Costs of asthma increased significantly in poorly controlled compared with somewhat controlled and well-controlled asthma ($7009.8 vs. $2725.3 vs. $1517.3, respectively; p < .001). After stratification for severity, a significant cost increase in the poorly controlled asthma group was observed only for indirect costs and not for direct costs. A multivariate analysis showed that female gender was a risk factor for increased indirect costs.

CONCLUSION

The burden of asthma was higher both for patients with severe persistent asthma and for patients with poorly controlled asthma. More effective strategies are needed to improve control status, particularly targeting patients with severe asthma.

Residential environmental risk factors for childhood asthma prevalence in metropolitan and semirural cities in Korea

To identify the association between residential environmental risk factors and the prevalence of childhood asthma, the authors surveyed the prevalence of asthma, the residential environmental risk factors of 1819 elementary school students, and air pollution in metropolitan (Seongbuk), and semirural (Andong) areas. Although there was no significant difference in the prevalence of self-reported asthma (SA) between the 2 geographic areas (12.8% vs 13.6%), the prevalence of physician-diagnosed asthma (PDA) in Andong (15.0%) was significantly higher than that in Seongbuk (6.8%). After adjusting for confounding factors, logistic regression suggested that there were significant differences in size of the house (adjusted odds ratio [aOR] = 1.82), medical insurance (aOR = 2.59), and number of residents in the household (aOR = 1.54) between the SA and non-SA groups. There was a significant difference in the area of residence (aOR = 2.12) between the PDA and non-PDA groups. In conclusion, residential environmental risk factors and the area of residence affect the prevalence of childhood asthma.

Effect of an individualised education programme on asthma control, inhaler use skill, asthma knowledge and health-related quality of life among poorly compliant Korean adult patients with asthma

AIMS AND OBJECTIVES

This study assessed the effect of an individualised education programme on asthma control, inhaler use, asthma knowledge and health-related quality of life among poorly compliant adult Korean patients with asthma.

BACKGROUND

Previous studies show that proper educational strategies are necessary to increase asthma knowledge and skills to improve patients' self-management and health-related quality of life.

DESIGN

A one-group quasi-experimental design with repeated measurements.

METHODS

Adult patients with asthma (n = 101) were recruited from University hospital located in K City, Korea. Three interventions consisting of 30-minute sessions of individualised education were provided by an education team. Peak expiratory flow rate (PEFR), daily record card (DRC) scores, skill scores for use of metered dose inhaler, level of asthma knowledge and health-related quality of life scores were obtained before the intervention and 2-4 and 4-8 weeks after the intervention. One-way repeated measures analysis of variance was used to identify the effect of the education programme on the dependent variables.

RESULTS

Peak expiratory flow rate, DRC scores, inhaler using skill scores and health-related quality of life scores benefitted from intervention, whereas knowledge score did not. The effect on the PEFR and DRC score was sustained, with that of inhaler use skill increased over time from 4-8 weeks. However, the health-related quality of life effect was not sustained for 4-8 weeks after the intervention.

CONCLUSIONS

Repetitive education and innovative education methods may be needed to improve and to maintain pulmonary function, symptom control, asthma knowledge and health-related quality of life of poorly compliant adult Korean patients with asthma.

RELEVANCE TO CLINICAL PRACTICE

This study confirmed the importance of education for patients suffering from asthma in managing their symptoms and promoting their quality of life.

Physicians' preferences for asthma guidelines implementation

Purpose

Patient care based on asthma guidelines is cost-effective and leads to improved treatment outcomes. However, ineffective implementation strategies interfere with the use of these recommendations in clinical practice. This study investigated physicians' preferences for asthma guidelines, including content, supporting evidence, learning strategies, format, and placement in the clinical workplace.

Methods

We obtained information through a questionnaire survey. The questionnaire was distributed to physicians attending continuing medical education courses and sent to other physicians by airmail, e-mail, and facsimile.

Results

A total of 183 physicians responded (male to female ratio, 2.3:1; mean age, 40.4±9.9 years); 89.9% of respondents were internists or pediatricians, and 51.7% were primary care physicians. Physicians preferred information that described asthma medications, classified the disease according to severity and level of control, and provided methods of evaluation/treatment/monitoring and management of acute exacerbation. The most effective strategies for encouraging the use of the guidelines were through continuing medical education and discussions with colleagues. Physicians required supporting evidence in the form of randomized controlled trials and expert consensus. They preferred that the guidelines be presented as algorithms or flow charts/flow diagrams on plastic sheets, pocket cards, or in electronic medical records.

Conclusions

This study identified the items of the asthma guidelines preferred by physicians in Korea. Asthma guidelines with physicians' preferences would encourage their implementation in clinical practice.

Customized Asthma Control Test with reflection on sociocultural differences

We evaluated the utility and feasibility of customizing Asthma Control Test (ACT) items to generate a Korean Asthma Control Test (KACT) specific for Korean patients. We surveyed 392 asthma patients with 19 items, selected to reflect the Korean sociocultural context. Guideline ratings were integrated with the evaluations of specialists (i.e., using both guide base rating together with specialist's rating), and items with the greatest discriminating validity were identified. Stepwise regression methods were used to select items. KACT scale scores showed significant differences between the asthma control ratings generated by integrating ratings (r=0.77, P<0.001), by specialist's evaluations (r=0.54, P<0.001), or by FEV(1) percent predicted (r=0.39, P<0.001). Specialist's and guideline ratings detected 56% and 48.6% of patients with well-controlled asthma, respectively. However, the integrated ratings indicated that only 34.3% of the patients in the test sample were well controlled. The overall agreement between KACT and the integrated rating ranged from 45% to 78%, depending on the cut-off points used. It is possible to formulate a valid, useful country-specific diagnostic tool for the assessment of asthma patients based on the original ACT that reflect differences in sociocultural context.

Asthma management in the developing world: achievements and challenges

Asthma is a serious global health problem that affects people of all ages. The best strategy to reduce the mortality and morbidty of asthma is evidence-based management based on guidelines. National and international guidelines are available worldwide but they are not being implemented. The main barriers to implementation include difficulties in implementing a structured-care approach, advocated by guidelines in different healthcare systems, and patient noncompliance. Additional barriers in developing countries include poverty, inadequate resources and poor infrastructure. Many of these barriers are potentially correctable or ameliorable, and the goal of guideline implementation is to translate evidence-based asthma-management recommendations into real-life practice to improve patient health and reduce healthcare cost. This article reviews the challenges and current status of asthma management and highlights the new global initiatives for bringing optimal asthma care to asthma sufferers in resource-poor countries.

Past, present, and future of allergy in Korea

Korean allergology has made great progress in keeping pace with global scientific advances in spite of a short history. Outstanding academic and scientific researches have been performed in a variety of allergy fields in Korea. Epidemiologic studies revealed increasing prevalence of asthma and allergic diseases and considerable morbidity and mortality in Korea. Novel inhalant allergens such as citrus red mite and two-spotted spider mite as causes of asthma and allergic rhinitis have been discovered and reported in Korea. Bidirectional translational researches have been performed and are underway to elucidate the pathogenesis of asthma and allergy, mechanisms of airway inflammation and remodeling, and new therapeutic modalities for asthma and allergic diseases. Experimental asthma models of different phenotypes according to exposed levels of lipopolysaccharide or double-stranded RNA suggested the crucial role of the innate immunity in the development of allergic airway inflammation and a new insight for asthma pathogenesis, in which both Th1 and Th2 inflammation are involved. In the field of genetic researches, numerous genetic associations with asthma and asthma-related phenotypes, such as atopy, IgE production, and airway hyperresponsiveness, have been demonstrated in Korean population. The Easy Asthma Management (EAM) program, a computer-assisted asthma management program, is anticipated to facilitate the achievement of more successful clinical outcomes by filling the gaps between guidelines and actual practices. The Integration of these multi-disciplinary allergy research resources and translation of scientific achievements to the bedside and society will lead to better allergy and asthma control in Korea.

Pharmacogenomic approaches to asthma treatment

Major classes of medication in asthma management include bronchodilating beta2-agonists, anti-inflammatory inhaled corticosteroids, leukotriene modifiers and theophyllines. However, all asthmatics do not respond to the same extent to a given medication. Available data suggest that a substantial range of individual variability, as much as 70%, may be due to genetic characteristics of each patient. Pharmacogenomics offers the potential to optimize medications for individual asthmatics by using genetic information to improve efficacy or avoid adverse effects. The best-studied case of the potential contribution of pharmacogenomics to treatment response in asthma comes from studies on human beta2 adrenergic receptors. In addition, genetic variation in beta2-adrenergic receptor (Arg16Gly) may predict response to anticholinergics for the treatment of asthma. In case of inhaled corticosteroids, a recent investigation using a traditional SNP-based approach identified a gene for corticotropin releasing hormone receptor 1 as a potential marker of response. Another major pathway that has been investigated is the pathway underlying response to cysteinyl leukotriene receptor antagonist. It is likely that in the near future, pharmacogenomic approaches based on individual genetic information will be introduced into an asthma treatment guideline and this guideline will allow us to identify those who have the best chance to respond to a specific medication.

Prevalence of depression and anxiety in outpatients with chronic airway lung disease

BACKGROUND/AIMS

Patients with chronic airway lung diseases often experience depression and anxiety, but little information is available regarding Koreans with these conditions. We thus assessed depression and anxiety in Korean patients with chronic airway lung diseases.

METHODS

The degree of depression and anxiety in 84 outpatients with chronic obstructive pulmonary disease (COPD), 37 with asthma, 33 with bronchiectasis, and 73 healthy controls were evaluated by the Beck Depression Inventory (BDI) and the State-Trait Anxiety Inventory (STAI).

RESULTS

The patients with COPD and bronchiectasis had higher BDI scores and were more likely than controls to experience depression ([COPD, 17; range, 0 to 42; prevalence, 55%], [bronchiectasis, 16; range, 3 to 51; prevalence, 55%], [controls, 13; range, 0 to 31; prevalence, 30%], p < 0.05). The state-anxiety scores of the patients were higher than those of the controls, but only the bronchiectasis group demonstrated a higher frequency of state-anxiety compared with the controls (39 vs. 16%, patients vs. controls, p = 0.015). Among all patients, 22% presented with concomitant depression and state-anxiety, and 25% demonstrated depression and trait-anxiety. Depression was positively correlated with both state-anxiety (r = 0.644) and trait-anxiety (r = 0.597, p < 0.0001). Irrespective of individual diagnosis, post-bronchodilator FEV(1) (odds ratio [OR], 0.972; p = 0.027) and smoking history (OR, 3.894; p = 0.018) were independent risk factors for depression in patients with chronic airway lung diseases.

CONCLUSIONS

Chronic airway lung diseases are associated with depression and/or anxiety, particularly in those with a higher airflow limitation and/or history of smoking.

Factors associated with health-related quality of life among low-compliant asthmatic adults in Korea

This cross-sectional descriptive study was conducted to identify the factors associated with health-related quality of life (HRQoL) in low-compliant Korean adults with asthma. The sample consisted of 178 patients referred by a physician to the education clinic at a University hospital in Korea. Stepwise multiple regression analysis revealed that previous hospital admissions, recent asthma-related symptoms within the previous week, lower peak expiratory flow rate, and lower level of asthma knowledge were independently associated with lower HRQoL and accounted for 46% of the total variance. Health care providers should focus on these factors to increase perceptions of HRQoL among low-compliant patients. Interventional strategies need to be developed to emphasize the importance of compliance to the self-monitoring regimen and management protocols.

Comparison of the clinical efficacy and safety of salmeterol/fluticasone propionate versus current care in the management of persistent asthma in Korea

OBJECTIVES

In the Asia-Pacific region there is a general preference for prescribing oral over inhaled medications for the treatment of asthma. This study compared inhaled salmeterol/fluticasone propionate therapy (SFC) with physician-determined current care (CC) in the management of persistent asthma in Korea.

METHODS

Adult patients with a documented history of reversibility in FEV(1) (>or= 12%) or PEF (>or= 15%), were randomised in a 2:1 ratio to unblinded treatment with SFC (50/250 microg bd or 50/500 microg bd) via Diskus (N = 284) or CC (N = 140) for 52 weeks. Morning peak expiratory flow (PEF) (primary endpoint), exacerbations, asthma symptoms and patient-reported outcome measures were recorded.

TRIAL REGISTRATION

GSK study number:100614.

RESULTS

At baseline, mean morning PEF in the SFC and CC group was 374 and 401 L/min respectively. The adjusted mean morning PEF at 52 weeks was 423 +/- 3 and 396 +/- 4 L/min for SFC and CC respectively (treatment difference of 27 +/- 5 in favour of SFC; 95% CI 17, 37; p < 0.0001). The mean rate of exacerbations over 52 weeks was significantly lower in the SFC group (SFC/CC odds ratio 0.57; 95% CI 0.44, 0.74; p < 0.0001). Treatment with SFC also resulted in a significantly greater improvement in asthma symptoms, in the number of patients assessed to have well controlled asthma (Asthma Control Test score >or= 20), and in a clinically significant improvement in overall Quality of Life. The incidence of adverse events was low and similar between the two groups and events were of the type expected in this population.

CONCLUSIONS

The results of this open-label, randomised study showed that SFC provided greater asthma control than CC in the management of persistent asthma.

Correlation between the Korean version of Asthma Control Test and health-related quality of life in adult asthmatics

The Asthma Control Test (ACT) is a patient-completed questionnaire developed to assess asthma control. Health-related quality of life (HRQL) in asthmatics has shown relatively low correlations with parameters of asthma control and the relationship between the ACT and HRQL in asthmatics is yet unclear. Because revalidations of translated versions of questionnaires are critical for its utilization, we first sought to validate the Korean version of ACT and then to evaluate the relationship between the ACT and HRQL. Patients (n=117) completed the ACT and asthma-related quality of life questionnaire (AQLQ) at 3 physician visits. Pulmonary function was measured and an asthma specialist rated asthma control. The Korean version of ACT was found to be reliable, valid, and responsive to changes in asthma control over time up to three consecutive visits. ACT scores correlated significantly (p=0.001) with symptoms domain (r=0.72), activity domain (r=0.65), emotional domain (r=0.69), and environmental domain (r=0.67) of AQLQ. In conclusion, the Korean version of the ACT was found to be a reliable and valid tool for measuring asthma control, and to correlate well with AQLQ scores. Moreover, the ACT was responsive to changes in AQLQ scores over time.