To validate the prevalence rate of symptoms of asthma produced by the phase I ISAAC (International Study of Asthma and Allergies in Childhood) study, hypertonic saline challenge test was carried out during the phase II study at a year after the phase I study. For the phase II study, six middle schools from three cities in the phase I study were selected. Finally, 499 children who responded to both studies were analyzed. All subjects were asked to complete the written questionnaire (WQ) first, followed by a video questionnaire (AVQ 3.0) during the phase I study. Of the 499 children, only 19 (3.8%) were positive to the hypertonic saline bronchial challenge test. The degree of agreement between responses to the two corresponding questions "wheezing at rest" and "nocturnal wheeze" in the AVQ 3.0 and WQ were moderate and weak with a Kappa indices of 0.45 and 0.23, respectively. The question on "severe wheeze" in the AVQ 3.0 had the highest Youden's index among the five questions related to asthma symptoms in the previous 12 months, but its specificity was low whereas it 's sensitivity was 1.0. There was no consistency of priority between the two questionnaires in predicting bronchial hyperreactivity in a group of Korean schoolchildren. Therefore we need to develop more appropriate WQ or AVQ to compare the prevalences of asthma to other countries.
Adolescent ; Asthma/diagnosis* ; Asthma/epidemiology ; Asthma/etiology ; Bronchial Hyperreactivity/complications ; Bronchial Hyperreactivity/diagnosis* ; Bronchial Hyperreactivity/epidemiology ; Bronchial Provocation Tests ; Comparative Study ; Female ; Human ; Korea/epidemiology ; Language ; Male ; Prevalence ; Questionnaires* ; Random Allocation ; Respiratory Sounds ; Saline Solution, Hypertonic/diagnostic use ; Sampling Studies ; Videotape Recording ; Writing

Passive smoking is a major cause of respiratory morbidity, and is associated with increased bronchial responsiveness in children. To evaluate the effect of smoking by a parent on asthma symptoms, atopy, and airway hyperresponsiveness (AHR), we conducted a cross-sectional survey of 503 schoolchildren that involved questionnaires, spirometry, allergy testing, and a bronchial challenge test. If the PC20 methacholine was less than 16 mg/mL, the subject was considered to have AHR. The prevalence of a parent who smoked was 68.7%. The prevalence of AHR was 45.0%. The sensitization rate to common inhalant allergens was 32.6%. Nasal symptoms such as rhinorrhea, sneezing, nasal itching, and nasal obstruction were present in 42.7%. Asthma symptoms such as cough and wheezing were present in 55.4%. The asthma symptoms were significantly more prevalent in children who had a parent who smoked than in those whose parents did not. The nasal symptoms, atopy, and AHR did not differ according to whether a parent smoked. In a multiple logistic regression model, the asthma symptoms and atopy were independently associated with AHR, when adjusted for confounding variables. Passive smoking contributed to asthma symptoms in schoolchildren and was not an independent risk factor of airway hyperresponsiveness in an epidemiological survey.
Adult ; Asthma/*epidemiology/physiopathology ; Bronchial Hyperreactivity/*epidemiology/physiopathology ; Child ; Data Collection ; Female ; Human ; Hypersensitivity/*epidemiology/physiopathology ; Male ; Parents ; Prevalence ; Risk Factors ; Support, Non-U.S. Gov't ; Tobacco Smoke Pollution/*adverse effects/*statistics & numerical data

The bronchial pathology of asymptomatic airway hyperreponsiveness (AHR) subjects is not well understood, and the role of atopy in the development of airway remodeling is unclear. The aim of this study was to evaluate whether atopy is associated with airway remodeling in asymptomatic AHR subjects. Five groups, i.e., atopic or non-atopic subjects with asymptomatic AHR, atopic or non-atopic healthy controls, and subjects with mild atopic asthma, were evaluated by bronchoscopic biopsy. By electron microscopy, mean reticular basement membrane (RBM) thicknesses were 4.3+/-1.7 micrometer, 3.4+/-1.8 micrometer, 2.5+/-1.5 micrometer, 2.6+/-1.1 micrometer, and 2.3+/-1.2 micrometer in the mild atopic asthma, atopic and non-atopic asymptomatic AHR, atopic and nonatopic control groups, respectively (p=0.002). RBM thicknesses were significantly higher in the mild atopic asthma group and in the atopic asymptomatic AHR group than in the other three groups (p=0.048). No significant difference in RBM thickness was observed between the atopic asymptomatic AHR group and the mild atopic asthma group (p>0.05), nor between non-atopic asymptomatic AHR group and the two control groups (p>0.05). By light microscopy, subepithelial layer thicknesses between the groups showed the same results. These findings suggest that RBM thickening occurs in subjects with atopic asymptomatic AHR, and that atopy plays an important role in airway remodeling.
Adult ; Asthma/epidemiology/*pathology ; Basement Membrane/*pathology/ultrastructure ; Biopsy ; Bronchi/pathology ; Bronchial Hyperreactivity/epidemiology/*pathology ; Bronchoscopy ; Female ; Fibrosis ; Follow-Up Studies ; Humans ; Hypersensitivity, Immediate/*epidemiology ; Male ; Microscopy, Electron ; Respiratory Mucosa/*pathology/ultrastructure ; Risk Factors

Although the association between obesity and asthma has been well documented, the nature of this association has yet to be clarified. The aim of this study was to examine the association of body mass index (BMI), lipid profiles, and atopy, wheezing, and lung function in older adults living in a rural area in Korea. BMI (kg/m2), lipid profiles, skin prick test, spirometry, and questionnaire including airway symptoms were obtained in a cross-sectional survey in 707 (259 males and 448 females) older adults (aged 50 to 93; mean, 65.7 yr) living in a high-altitude rural area in Korea. The prevalence of self-reported wheezing was 17.1% (121/707). The prevalence of atopy was 13.8%. The mean of BMI was 23.3+/-0.13 (14.6-32.8). The BMI was higher in females than in males (23.8+/-0.16 vs 22.4+/-0.17; p<0.01). The prevalence of wheezing was higher in group with BMI> or = 25 than in group with BMI<25 [57/201 (28.3%) vs 64/505 (12.6%), p<0.01]. The BMI was higher in group with wheezing than in group without wheezing (24.3+/-0.34 vs 23.1+/-0.13, p<0.01). No association between BMI and atopy was found. These findings suggest that BMI associated with wheezing in older adults.
Aged ; Aged, 80 and over ; *Altitude ; Asthma/*epidemiology/metabolism ; *Body Mass Index ; Bronchial Hyperreactivity/immunology ; Comorbidity ; Female ; Humans ; Hypersensitivity/epidemiology/immunology ; Korea/epidemiology ; Lipids/blood ; Male ; Middle Aged ; Questionnaires ; Respiratory Function Tests ; *Respiratory Sounds/immunology ; Skin Tests

BACKGROUND: An association between obesity and asthma has been reported. The prevalence of airway hyperresponsiveness (AHR), results of skin prick tests, body mass index (BMI), and asthma symptoms were examined in schoolchildren. METHODS: The results of BMI (kg/m2) determination, skin prick testing, spirometry, asthma questionnaires, and methacholine challenge tests were obtained in a cross-sectional survey of 667 schoolchildren. The methacholine concentration causing a 20% fall in FEV1 (PC20) was used as the threshold of AHR. If the PC20 was less than 16 mg/mL, the subject was considered to have methachloine mediated AHR. RESULTS: The mean BMI was 17.1+/-0.09 kg/m2. The prevalence of AHR was 42.7%. The sensitization rate to common inhalant allergens was 30.3%. PC20 in children with BMIs >or=17.1 kg/m2 was significantly lower than that in children with BMIs 17.1 kg/m2. The mean BMIs of boys and girls were not significantly different. The levels of PC20 by sex were not different. The children were grouped by sex into percentile of BMI. PC20 in boys was lower in the obese group than in the non-weight and overweight groups (p<0.05). PC20 in boys and girls with atopy was significantly lower than in those without atopy. In a multiple logistic regression model that included all of the children and adjusted for confounding variables, independent associations with AHR were seen with BMI, asthma symptoms, and atopy . CONCLUSIONS: BMI had an association with AHR in school-age boys.
Sex Factors ; *Schools ; Risk Factors ; Questionnaires ; Obesity/*physiopathology ; Methacholine Chloride/*pharmacology ; Male ; Korea/epidemiology ; Hypersensitivity, Immediate/epidemiology/physiopathology ; Humans ; Health Surveys ; Female ; Comorbidity ; Child ; Bronchial Hyperreactivity/epidemiology/*physiopathology ; Body Mass Index ; Asthma/*physiopathology ; Age Factors

BACKGROUND/AIMS: We sought to increase our understanding of the rhinitis-asthma relationship and improve strategies for the treatment of patients with these diseases. The aim of this study was to identify a connection between upper airway inflammation and lower airway responsiveness. METHODS: We counted eosinophils on nasal smears, and performed spirometry, allergic skin tests, and methacholine challenge tests in 308 schoolchildren plus a questionnaire on respiratory symptoms. The methacholine concentration causing a 20% fall in forced expiratory volume in 1 second (PC20 < 25 mg/mL) was used as the threshold of bronchial hyperresponsiveness (BHR). RESULTS: In total, 26% of subjects had positive nasal eosinophils on a smear, and 46.2% of subjects had BHR at < 25 mg/mL methacholine PC20. Nasal symptoms were higher in subjects with than without nasal eosinophils (p = 0.012). Asthma symptoms did not differ between subjects with and without nasal eosinophils. Nasal eosinophils were higher in subjects with atopy than those without (p = 0.006), and there was no difference in PC20 methacholine according to atopy (15.5 +/- 1.07 vs. 17.5 +/- 0.62; p > 0.05). No difference in BHR was detected when comparing subjects with and without nasal eosinophils. There were significant differences in the PC20 between subjects with greater than 50% nasal eosinophils and without nasal eosinophils (11.01 +/- 2.92 mg/mL vs. 17.38 +/- 0.61 mg/mL; p < 0.001). CONCLUSIONS: These findings demonstrated that nasal eosinophilic inflammation might contribute to lower airway responsiveness in schoolchildren, based on an epidemiological survey.
Adolescent ; Age Distribution ; Age Factors ; Asthma/diagnosis/*epidemiology/physiopathology ; Bronchial Hyperreactivity/diagnosis/*enzymology/physiopathology ; Bronchial Provocation Tests ; Child ; Eosinophilia/diagnosis/*epidemiology/immunology ; Eosinophils/immunology ; Female ; Health Surveys ; Humans ; Intradermal Tests ; Leukocyte Count ; Lung/*physiopathology ; Male ; Nasal Mucosa/*immunology ; Republic of Korea/epidemiology ; Rhinitis/diagnosis/*epidemiology/immunology ; Spirometry ; Surveys and Questionnaires

The risk of asthma has been increasing in parallel with use of acetaminophen, which is a potential source of oxidative stress. Toll-like receptor 4 (TLR4) plays a critical role not only in innate immunity, but also in mediating reactive oxygen species induced inflammation. Therefore, we investigated associations between acetaminophen usage and TLR4 polymorphism on asthma and bronchial hyperresponsiveness (BHR). The number of 2,428 elementary school children in Seoul and Jeongeup cities was recruited. Subjects who used acetaminophen with a family history of asthma had an increased risk of both asthma diagnosis ever and current asthma. Individuals with CT+TT genotypes at the TLR4 polymorphism, in combination with acetaminophen usage, also demonstrated an increased risk of asthma diagnosis ever (aOR, 2.08; 95% confidence interval [CI], 1.10-3.92). Family history of asthma and acetaminophen usage were risk factors for BHR. Although TLR4 was not an independent risk factor for BHR, individuals with CT+TT genotypes at the TLR4 polymorphism had an increased risk of BHR when combined with acetaminophen usage (aOR, 1.74; 95% CI, 1.03-2.94). In conclusion, acetaminophen usage may be associated with asthma and BHR in genetically susceptible subjects. This effect may be modified by polymorphism at TLR4.
Acetaminophen/*adverse effects/therapeutic use ; Adolescent ; Asthma/chemically induced/epidemiology/*genetics ; Bronchial Hyperreactivity/chemically induced/epidemiology/*genetics ; Child ; Cross-Sectional Studies ; Eosinophils/immunology ; Female ; Genetic Predisposition to Disease ; Genotype ; Humans ; Immunoglobulin E/blood/immunology ; Inflammation/immunology ; Male ; Oxidative Stress/drug effects ; Polymorphism, Single Nucleotide ; Questionnaires ; Reactive Oxygen Species/immunology ; Risk ; Risk Factors ; Toll-Like Receptor 4/*genetics