Recent Wheeze Research Articles

Diverging prevalences and different risk factors for childhood asthma and eczema: a cross-sectional study

ObjectiveTo compare the prevalences of and risk factors for asthma, wheeze, hay fever and eczema in primary schoolchildren in Aberdeen in 2014.DesignCross-sectional survey.SettingPrimary schools in Aberdeen, North-East Scotland.ParticipantsChildren in Scottish...

Age-Dependent Cut Points for Airway Hyperresponsiveness to Distinguish Asthma from Healthy Children in Methacholine Challenge Test

M O N D A Y 574 Age-Dependent Cut Points for Airway Hyperresponsiveness to Distinguish Asthma from Healthy Children in Methacholine Challenge Test Ji-Won Kwon, MD, Eun Lee, Song-I. Yang, MD, Young-Ho Ho Jung, MD, Ju-Hee Seo, MD, Byoung-Ju Kim, MD, PhD, Hyo-Bin Kim, MD, PhD, So Yeon Lee, MD, PhD, Woo Kyung Kim, MD, PhD, Jung Yeon Shim, MD, PhD, Soo-Jong Hong, MD, PhD; Department of Pediatrics, Seoul National University Bundang Hospital, Seongnam, South Korea, Department of Pediatrics, Childhood Asthma Atopy Center, Research Center for Standization of Allergic Diseases, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea, Department of Pediatrics, Childhood Asthma Atopy Center, Asan Medical Center, University of Ulsan College of Medicine, Seoul, South Korea, South Korea, Department of Pediatrics, Korea Cancer Center Hospital, Seoul, South Korea, Department of Pediatrics, Hae-undae Paik Hospital, Inje University College of Medicine, Busan, South Korea, Department of Pediatrics, Inje University Sanggye Paik Hospital, Seoul, South Korea, Department of Pediatrics, Hallym University College of Medicine, Seoul, South Korea, Research Center for Standardization of Allergic Diseases, Seoul, South Korea, South Korea, Department of Pediatrics, Seoul Paik Hospital, Inje University College of Medicine, Seoul, South Korea, Department of Pediatrics, Kangbuk Samsung Hospital, Sungkyunkwan University College of Medicine, Seoul, South Korea. RATIONALE: Cut-off points of bronchial provocation tests to distinguish asthma in children have not been fully investigated. We evaluated agedependent cut-off values of bronchial provocation test to determine asthma in children. METHODS: A total of 3,045 subjects aged from 6 to 19 years old were undertaken a methacholine challenge test. All subjects were classified into 3 groups. The group 1 included patients with clinical asthma diagnosed by pediatric allergist. The group 2 included 280 subjects with a history of recent wheeze, physician diagnosed asthma, or recent asthma treatment by a Korean version of ISAAC questionnaire from population-based researches. The group 3 included healthy subjects (n52,399) except group 2 from population studies. Receiver operating characteristics curves to determine the cut-off values for clinical asthma were analyzed between group 1 and 3, and also analyzed between group 2 and 3. RESULTS: From ROC analysis between group 1 and 3, cut-off values for determining asthma were increased with age. Cut-off of PC20 were 5.95 mg/ml at age 6, 9.13 mg/ml at age 7, 11.77 mg/ml at age 8, 12.62 mg/ml at age 9, 14.94 mg/ml at age 10, 16.61 mg/ml at age 11, and 24.60 mg/ ml at age more than 15 years. All cut-off points were statistically significant. In ROC analysis between group 2 and 3, a significant cut-off value was only found in subjects aged more than 15 years. CONCLUSIONS: The reference values of PC20 for determining asthma distinguished from healthy children were increased with age. Age-dependent interpretation is needed in evaluating AHR in children with asthma.

Effect of urban vs. rural residence on the association between atopy and wheeze in Latin America: findings from a case-control analysis.

BackgroundThe association between atopy and asthma is attenuated in non-affluent populations, an effect that may be explained by childhood infections such as geohelminths.ObjectiveTo investigate the association between atopy and wheeze in schoolchildren living in urban and rural areas of Ecuador and examine the effects of geohelminths on this association.MethodsWe performed nested case–control studies among comparable populations of schoolchildren living in rural communities and urban neighbourhoods in the Province of Esmeraldas, Ecuador. We detected geohelminths in stool samples, measured recent wheeze and environmental exposures by parental questionnaire, and atopy by specific IgE (sIgE) and skin prick test (SPT) reactivity to aeroallergens.ResultsAtopy, particularly sIgE to house dust mite (HDM), was more strongly associated with recent wheeze in urban than rural schoolchildren: (urban, adj. OR 5.19, 95% CI 3.37–8.00, P < 0.0001; rural, adj. OR 1.81, 95%CI 1.09–2.99, P = 0.02; interaction, P < 0.001). The population fractions of wheeze attributable to atopy were approximately two-fold greater in urban schoolchildren: SPT to any allergen (urban 23.5% vs. rural 10.1%), SPT to HDM (urban 18.5% vs. rural 9.6%), and anti-HDM IgE (urban 26.5% vs. rural 10.5%), while anti-Ascaris IgE was related to wheeze in a high proportion of rural (49.7%) and urban (35.4%) children. The association between atopy and recent wheeze was attenuated by markers of geohelminth infections.ConclusionsOur data suggest that urban residence modifies the association between HDM atopy and recent wheeze, and this effect is explained partly by geohelminth infections.

Validation of the Korean version of the European Community Respiratory Health Survey screening questionnaire for use in epidemiologic studies for adult asthma.

BackgroundStandardized questionnaire is one of key instruments for general population surveys.ObjectiveThe present study aimed to develop and validate the Korean version of the European Community Respiratory Health Survey (ECRHS) screening questionnaire for adult asthma surveys.MethodsThe ECRHS screening questionnaire was translated into Korean language according to the international criteria. Study participants were prospectively recruited from six referral hospitals and one health check-up center. Comprehensibility of the translation was tested in a pilot study of 10 patients. The reliability was evaluated by internal consistency and test-retest repeatability. Validity was assess with regard to physician-diagnosed asthma.ResultsA total of 100 adult asthma patients and 134 volunteers were recruited. Reliability was examined for 10 items in 100 asthmatics; Cronbach α coefficients were 0.84, and test-retest repeatability was good (Cohen κ coefficient, 0.71-1.00). Validity was assessed for 8 items in 234 participants; in particular, 'recent wheeze' showed a high sensitivity (0.89) for physician-diagnosed asthma. 'Recent asthma attack' and 'current asthma medication' showed high specificity (0.96-0.98).ConclusionThe present study demonstrated that the Korean version of the ECRHS screening questionnaire was comprehensible, reliable and valid. We suggest the questionnaire to be utilized in further epidemiological studies for asthma in Korean adult populations.

P97 Diverging Trends In Prevalences Of Asthma, Eczema And Hayfever In Children Aged 9-12 Years

Introduction The prevalences of childhood asthma, eczema and hayfever have been recorded in our local population since 1964. The prevalence of a lifetime history of asthma rose from 4% in 1964 to a peak of 28% in 2004 before falling back to 22% in 2009. Wheeze in the past 12 months fell from 19% in 2004 to 16% in 2009. Lifetime prevalences of eczema and hay fever were approximately 5% in 1964 and had risen to 30% and 25% in 2004 and 2009. Here we present the results of our 2014 survey where we tested the hypothesis that eczema and hayfever prevalence will have followed the earlier trend for asthma and fallen since 2009. Methods Children aged 9 to 12 years attending local primary schools were eligible. The questionnaire used in previous surveys was distributed to children by teaching staff, completed by parents at home and returned directly to the researchers. Results Forty-seven schools were invited to participate of whom 41 took part. There were 4175 questionnaires distributed and 1378 returned (33%). The mean (SD) age was 10.9 (1.1) and 50% were boys. A lifetime history of asthma was reported in 17%. Lifetime prevalences of eczema and hay fever were 31% and 30% respectively. Wheeze in the past 12 months was reported in 13%. Conclusions The proportion of children with a history of ever having had asthma and of recent wheeze continues to fall in our population at a time when the prevalences of eczema and hayfever remained static (see Figure). There was a low response rate in this survey and the results should be interpreted with some caution but the findings suggest different underlying mechanisms for asthma and other “allergic” conditions.

Breastfeeding and childhood asthma: systematic review and meta-analysis.

Asthma and wheezing disorders are common chronic health problems in childhood. Breastfeeding provides health benefits, but it is not known whether or how breastfeeding decreases the risk of developing asthma. We performed a systematic review and meta-analysis of studies published between 1983 and 2012 on breastfeeding and asthma in children from the general population. We searched the PubMed and Embase databases for cohort, cross-sectional, and case-control studies. We grouped the outcomes into asthma ever, recent asthma, or recent wheezing illness (recent asthma or recent wheeze). Using random-effects meta-analyses, we estimated pooled odds ratios of the association of breastfeeding with the risk for each of these outcomes. We performed meta-regression and stratified meta-analyses. We included 117 of 1,464 titles identified by our search. The pooled odds ratios were 0.78 (95% confidence interval: 0.74, 0.84) for 75 studies analyzing "asthma ever," 0.76 (95% confidence interval: 0.67, 0.86) for 46 studies analyzing "recent asthma," and 0.81 (95% confidence interval: 0.76, 0.87) for 94 studies analyzing recent wheezing illness. After stratification by age, the strong protective association found at ages 0-2 years diminished over time. We found no evidence for differences by study design or study quality or between studies in Western and non-Western countries. A positive association of breastfeeding with reduced asthma/wheezing is supported by the combined evidence of existing studies.

Polycyclic aromatic hydrocarbon exposure, obesity and childhood asthma in an urban cohort

BackgroundExposure to traffic-related air pollutants, including polycyclic aromatic hydrocarbons (PAHs) from traffic emissions and other combustion sources, and childhood obesity, have been implicated as risk factors for developing asthma. However, the interaction between these two on asthma among young urban children has not been studied previously. MethodsExposure to early childhood PAHs was measured by two week residential indoor monitoring at age 5–6 years in the Columbia Center for Children's Environmental Health birth cohort (n=311). Semivolatile [e.g., methylphenanthrenes] and nonvolatile [e.g., benzo(a)pyrene] PAHs were monitored. Obesity at age 5 was defined as a body mass index (BMI) greater than or equal to the 95th percentile of the year 2000 age- and sex-specific growth charts (Center for Disease Control). Current asthma and recent wheeze at ages 5 and 7 were determined by validated questionnaires. Data were analyzed using a modified Poisson regression in generalized estimating equations (GEE) to estimate relative risks (RR), after adjusting for potential covariates. ResultsNeither PAH concentrations or obesity had a main effect on asthma or recent wheeze. In models stratified by presence/absence of obesity, a significant positive association was observed between an interquartile range (IQR) increase in natural log-transformed 1-methylphenanthrene (RR [95% CI]: 2.62 [1.17–5.88] with IQRln=0.76), and 9-methylphenanthrene (2.92 [1.09–7.82] with IQRln=0.73) concentrations and asthma in obese children (n=63). No association in non-obese (n=248) children was observed at age 5 (Pinteraction<0.03). Similar associations were observed for 3-methylphenanthrene, 9-methylphenanthrene, and 3,6-dimethylphenanthrene at age 7. ConclusionsObese young children may be more likely to develop asthma in association with greater exposure to PAHs, and methylphenanthrenes in particular, than non-obese children.

Risk factors for respiratory symptoms in adults: The Busselton Health Study

The prevalence of reported doctor-diagnosed 'asthma' increased between 1990 and 2005-2007 in Busselton, Western Australia, accompanied by increased reported cough and phlegm but not recent wheeze. Possible reasons for the increase in diagnosed asthma include environmental exposures and diagnostic transfer. The aim of this study was to relate subject characteristics and exposures to the presence of wheeze and/or current cough/phlegm in the 2005-2007 survey. A gender- and age-stratified random sample of 2862 adults from the Busselton shire completed questionnaires regarding doctor-diagnosed asthma, respiratory symptoms and environmental exposures; and measures of anthropometry, spirometry, exhaled nitric oxide (eNO), airway hyperresponsiveness (AHR) and atopy. Associations between respiratory symptoms and subject characteristics were assessed in 2656 subjects. Wheeze was reported by 23% of subjects, cough/phlegm by 22% and both by 9%. The significant and independent correlates of wheeze were reflux symptoms, lung function, AHR, eNO, atopy, body mass index and smoking. The significant and independent correlates of cough/phlegm were reflux symptoms, lung function, smoking and dusty job. Subjects more likely to report only wheeze than only cough/phlegm were female, aged <40 years, atopic, had lower percentage predicted forced expiratory volume in one second (FEV1) or higher percentage predicted force vital capacity. A variety of risk factors was associated with wheeze or cough/phlegm or both. Increased non-allergic exposures may account for increased prevalence of reported cough and phlegm and may contribute to increased reported asthma in adults.

Reduced Infant Lung Function, Active Smoking, and Wheeze in 18-Year-Old Individuals

IMPORTANCE This is the first study to link reduced lung function in early life, before the development of symptoms, to wheeze in 18-year-olds. Additionally, the study gives insight into factors other than reduced lung function that are also associated with persistent wheeze in young adults. To test the hypothesis that reduced lung function in early life is associated with increased risk for persistent wheeze at age 18 years. Birth cohort study. Perth, Western Australia. Individuals followed up from age 1 month to 18 years. Maximal flow at functional residual capacity (V'maxFRC) was measured in 1-month-old infants who were followed up at ages 6, 12, and 18 years. Based on reported symptoms, individuals were categorized as having remittent wheeze, later-onset wheeze, persistent wheeze, and no wheeze. Smoking status was noted at age 18 years. Of the 253 individuals originally recruited, 150 were followed up at age 18 years; 37 of the 150 had recent wheeze. Compared with the no-wheeze group (n = 96), persistent wheeze (n = 13) was independently associated with reduced percentage of predicted V'maxFRC (mean reduction, 43%; 95% CI, 13-74). Compared with the no-wheeze group, persistent wheeze was also associated with atopy in infancy (odds ratio = 7.1; 95% CI, 1.5-34.5), maternal asthma (odds ratio = 6.8; 95% CI, 1.4-32.3), and active smoking (odds ratio = 4.8; 95% CI, 1.0-21.3). When only wheeze at age 18 years was considered, reduced percentage of predicted V'maxFRC was associated with wheeze at age 18 years only among current smokers (P = .04). Wheeze persisting from ages 6 to 18 years is associated with multiple factors, including reduced infant lung function, infant-onset atopy, maternal asthma, and active smoking. Wheeze at age 18 years (regardless of previous wheeze status) is associated with active smoking, but only among those with reduced lung function in infancy. These findings give unique insight into the cause of obstructive airways disease in 18-year-olds, and follow-up of this cohort might be expected to further extend our understanding.

Environmental Tobacco Smoke Exposure and Respiratory Complaints in Children Aged 0-13 Years: A Cross-sectional Study in South-Limburg, The Netherlands

Background: Two forms of environmental tobacco smoke (ETS) exposure have been described: second-hand smoke (SHS), which is the direct exposure to tobacco smoke; and third-hand smoke (THS), which is the exposure to residuals from tobacco smoke after the cigarette has been extinguished. The effects of SHS exposure on children’s respiratory health are known, but not of THS exposure. We evaluated the association between both exposures and respiratory complaints in children aged 0-13 years, and assessed whether the risk of respiratory complaints due to these exposures was higher in children with genetic predisposition for asthma compared to those without. Methods: A cross-sectional survey (91 items) was performed in 10,000 families with a child aged 0-13 years living in South-Limburg, the Netherlands, assessing child and family characteristics, child’s respiratory health, and parental smoking behaviour. Data were analyzed with (adjusted) multiple logistic regressions. Results: 1899 families responded. SHS exposure was not associated with an increased risk of respiratory complaints in children. THS exposure was associated with respiratory tract infections in the past 12 months (ORadjusted: 2.13; 95% CI: 1.04-4.36; p=0.04) and recent wheezing (ORadjusted: 2.61; 95%CI: 1.19-5.71; p=0.02) in children. There was no interaction between genetic predisposition for asthma and ETS exposure. Conclusions: Unlike previous studies, our study could not reveal a significant association between SHS exposure and an increased risk of respiratory complaints in children, most likely due to study limitations concerning cross-sectional design, response rate, selection bias and parental underreporting of SHS exposure to their children. THS exposure was significantly associated with an increased risk of respiratory complaints in children. This adds to the limited knowledge about the health effects of THS exposure in children and suggests that more research on this topic is needed. A genetic predisposition for asthma combined with ETS exposure did not increase the risk of respiratory complaints in children.

Effects of geohelminth infection and age on the associations between allergen‐specific IgE, skin test reactivity and wheeze: a case‐control study

BackgroundMost childhood asthma in poor populations in Latin America is not associated with aeroallergen sensitization, an observation that could be explained by the attenuation of atopy by chronic helminth infections or effects of age.ObjectiveTo explore the effects of geohelminth infections and age on atopy, wheeze, and the association between atopy and wheeze.MethodsA case-control study was done in 376 subjects (149 cases and 227 controls) aged 7–19 years living in rural communities in Ecuador. Wheeze cases, identified from a large cross-sectional survey, had recent wheeze and controls were a random sample of those without wheeze. Atopy was measured by the presence of allergen-specific IgE (asIgE) and skin prick test (SPT) responses to house dust mite and cockroach. Geohelminth infections were measured in stools and anti-Ascaris IgE in plasma.ResultsThe fraction of recent wheeze attributable to anti-Ascaris IgE was 45.9%, while those for SPT and asIgE were 10.0% and 10.5% respectively. The association between atopy and wheeze was greater in adolescents than children. Although Anti-Ascaris IgE was strongly associated with wheeze (adj. OR 2.24 (95% CI 1.33–3.78, P = 0.003) and with asIgE (adj. OR 5.34, 95% CI 2.49–11.45, P < 0.001), the association with wheeze was independent of asIgE. There was some evidence that the association between atopy and wheeze was greater in uninfected subjects compared with those with active geohelminth infections.Conclusions and clinical relevanceAtopy to house dust mite and cockroach explained few wheeze cases in our study population, while the presence of anti-Ascaris IgE was an important risk factor. Our data provided only limited evidence that active geohelminth infections attenuated the association between atopy and wheeze in endemic areas or that age modified this association. The role of allergic sensitization to Ascaris in the development of wheeze, independent of atopy, requires further investigation.

Perinatal factors and respiratory health in children

There is conflicting evidence regarding the associations between anthropometric birth measures and asthma and lung function in children, particularly for apparently healthy infants born at term. Our objective was to elucidate these relationships paying particular attention to features of study design and analysis that may threaten the validity of previous studies in this field. We analysed data from a cohort of children with a family history of asthma who were recruited antenatally. Anthropometric birth measures and potential confounders were recorded at birth and within the first year of life. Lung function and asthma outcomes were measured at 8years of age. Airway hyperresponsiveness (AHR) was measured by methacholine challenge. The potential for a reversal paradox, due to inclusion of covariates on the causal pathway, was investigated. Four hundred and fifty (73% of the initial cohort) children were tested at age 8years. Birth weight in the lowest tertile was associated with current asthma (OR 1.95, 95% CI 1.08, 3.54) and recent wheeze (OR 1.87, 95%CI 1.08, 3.24), but not with AHR (OR 1.37, 95% CI 0.68, 2.78). Birth weight was positively associated with lung function. Current height modified the relationship between birth length and lung function suggesting that post-natal growth has an effect on this relationship. Low birth weight is associated with a greater risk of current asthma and lower lung function at 8years in children with a family history of asthma. Current height should be treated as an effect modifier when investigating the fetal origins hypothesis.

P2-197 Case-control analysis of the effects of age and geohelminth infection on wheeze and atopy in the rural tropics

IntroductionEpidemiological data suggest that a minority of asthma cases in Latin America may be associated with allergic sensitisation which could be explained by the effect of environmental factors. The aim...

P2-198 Overweight associated with non-atopic wheeze in rural tropics

IntroductionThe parallel rise in prevalence of asthma and overweight/obesity in some Latin American countries has led to suggestions of a link between the two epidemics. The aim of this study...

Patterns of airway disease and the clinical diagnosis of asthma in the Busselton population

The aim of this study was to examine how objective measures related to lung function cluster in the general population and how the patterns relate to asthma and bronchitis as diagnosed by a doctor (DDA and DDB, respectively). A cross-sectional survey of an age-stratified random general population sample of 1,969 adults from the electoral register of Busselton (Australia) was performed in 2005-2007. Respiratory symptoms, DDA ever, DDB ever, recent wheezing and smoking history, together with anthropometric measurements, forced expiratory volume in 1 s (FEV₁) and forced vital capacity (FVC), methacholine challenge or bronchodilator response, exhaled nitric oxide (eNO), skin-prick tests to common allergens, and blood eosinophil and neutrophil counts were studied. Cluster analysis (variables sex, age, atopy, FEV₁ % predicted, FEV₁/FVC, airway hyperresponsiveness, eNO, log eosinphil count, log neutrophil count and body mass index) was used to identify phenotypic patterns. Seven clusters (subjects with DDA and DDB, respectively) were identified: normal males (n=467; 7 and 13%), normal females (n=477; 12 and 18%), obese females (n=250; 16 and 28%), atopic younger adults (n=330; 21 and 17%), atopic adults with high eNO (n=130; 30 and 25%), atopic males with reduced FEV₁ (n=103; 33 and 32%) and atopic adults with bronchial hyperreactivity (n=212; 40 and 26%). The clinical diagnosis of asthma (ever) and bronchitis (ever) is not specific for any of the clustering patterns of airway abnormality.

Risk factors for atopic and non-atopic asthma in a rural area of Ecuador

BackgroundAsthma has emerged as an important public health problem of urban populations in Latin America. Epidemiological data suggest that a minority of asthma cases in Latin America may be associated...

Exhaled nitric oxide and exercise‐induced bronchoconstriction in young wheezy children – interactions with atopy

The association between exercise-induced bronchoconstriction (EIB) and exhaled nitric oxide (FE(NO)) has not been investigated in young children with atopic or non-atopic wheeze, two different phenotypes of asthma in the early childhood. Steroid naïve 3- to 7-yr-old children with recent wheeze (n = 84) and age-matched control subjects without respiratory symptoms (n = 71) underwent exercise challenge test, measurement of FE(NO) and skin prick testing (SPT). EIB was assessed by using impulse oscillometry, and FE(NO) by standard online technique. Although FE(NO) levels were highest in atopic patients with EIB, both atopic and non-atopic wheezy children with EIB showed higher FE(NO) than atopic and non-atopic control subjects, respectively. In atopic wheezy children, a significant relationship between FE(NO) and the severity of EIB was found (r = 0.44, p = 0.0004), and FE(NO) was significantly predictive of EIB. No clear association between FE(NO) and EIB or predictive value was found in non-atopic wheezy children. Both atopic and non-atopic young wheezy children with EIB show increased FE(NO) levels. However, the association between the severity of EIB and FE(NO) is present and FE(NO) significantly predictive of EIB only in atopic subjects, suggesting different interaction between bronchial responsiveness and airway inflammation in non-atopic wheeze.

부모에 의한 간접흡연 및 부모의 알레르기성 질환력과 소아 천식과의 관계에 관한 연구

이 연구는 부모의 알레르기 질환력을 고려해 간접흡연 노출과 소아 천식의 관계를 밝히는 것을 목적으로 이루어졌다. 이를 위해 경기도의 농촌과 도시를 대표하는 두 개 지역 소재 3개 초등학교 학생을 대상으로 이루어진 설문조사 자료를 이용하였다. 이 자료 중 이 연구는 설문에 응답한 대상자 중 평생 천명, 최근 천명, 의사진단 천식을 비롯해 간접흡연, 부모 알레르기 질환 여부에 응답한 2,301명을 최종 분석 대상으로 삼았다. 천식 및 천명을 이 분형 종속 변수로 삼고 로지스틱 회귀 분석을 통해 최근 1년간 간접흡연에의 노출과 부모의 알레르기 질환력이 천식 및 천명 질환에 미치는 독립 적인 효과를 분석하였으며 둘 간의 상호작용 효과를 추정하였다. 분석 결과 아버지와 어머니의 알레르기성 질환 병력은 평생 천명, 최근 천명에 유의한 영향력을 미치는 것으로 나타났으며 어머니의 천식 병력의 경우에는 의사 진단 천식에도 유의한 영향을 미치는 것으로 밝혀졌다. 그러나 어머니나 아버지의 최근 흡연과 소아 천식과의 관계는 통계적 유의성을 확보하지 못했다. 부모의 알레르기 질환력과 간접흡연간의 상호작용효과는 ‘부모알레르기 질환도 없고 간접흡연 노출도 없는 집단’, ‘부모 알레르기 질환력은 없지만 최근 흡연 노출은 있는 집단’, ‘부모 알레르기 질환력은 있지만 최근 흡연 노출은 없는 집단’, 그리고 ‘부모 알레르기 질환도 있으며 간접흡연 노출도 있는 집단’을 비교해 평가하였다. 분석 결과 부모의 알레르기 질환력과 간접흡연의 노출간의 상호작용효과는 어머니의 최근 흡연의 경우에 자녀의 최근 천명에서 유의한 효과를 보였으며 아버지의 최근 흡연의 경우에는 평생 천명과 최근 천명에서 유의한 효과를 타나냈다. 부모의 알레르기 질환과 최근 어머니의 흡연이 모두 없는 집단에 비해서 두 요인 다 있는 집단에서 자녀의 최근 천명이 나타날 교차비는 4.83배(95%CI:189-12.33)로 높았다. 또 아버지가 최근 1년간 흡연을 했으며 부모의 알레르기 질환력이 있는 집단에서는 아버지가 흡연하지도 않고 부모의 알레르기질환도 없는 집단에 비해 자녀의 최근 천명이 나타날 확률이 2.50배(95%CI:1.34-4.70) 높았으며 평생천명이 나타날 확률 역시 2.47배(95%CI:1.64-3.72)높았다. 이러한 연구 결과는 부모의 알레르기 질환력이 있는 경우에는 간접흡연의 노출이 자녀의 천식 및 천명의 유의한 위험 요인이라는 사실을 보여 준다. 따라서 향후에는 간접흡연의 노출과 상호작용하는 특정한 유전자 군에 대한 연구가 필요 할 것이다. 또한 소아 천식의 위험을 낮추기 위해서는 부모의 금연을 중심으로 한 간접흡연 노출을 줄일 수 있는 개입이 필요하며 나아가 부모가 알레르기질환이 있는 집단에 대한 집중적인 금연 교육이 소아 천식을 효과적으로 줄일 수 있을 것으로 여겨진다. Objectives: This study was conducted to investigate whether joint effects between family allergy history and environmental tobacco smoke(ETS) by parents were associated with pediatric asthma and wheezing. Methods: The study objects of this study were 2301 element school students and their parents in an urban-rural areas of Gyeonggi-do. Pediatric asthma and wheezing were identified by measures of International Study of Asthma and Allergies in Childhood (ISAAC) questionnaires. We investigated history of parental allergy, ETS, and other socioeconomic status of both parent. Data were analyzed using logistic regression methods. Results: After adjusting other variables, children with maternal asthma history were more likely to be reported life time wheezing (OR: 3.79 95%CI:2.43-5.90), recent wheezing (OR:4.09 95%CI:2.28-7.38), and diagnostic asthma (OR:2.61 95%CI: 1.44-4.75). Paternal asthma history increasing risk of life time wheezing (OR 2.01 95%CI:1.19-3.38) and recent wheezing (OR:2.38 95%CI:1.24-4.56). Joint effect between parental allergy history and ETS significantly effected on child's life time wheezing and recent wheezing. The risks of life time wheezing (OR:2.47 95%CI:1.64-3.717) and recent wheezing (OR: 2.51 95%CI:1.34-4.69) were significantly higher than others without both factors. The risk of recent wheezing of children with maternal recent smoking and parental allergy history (OR:4.83 95%CI:1.89-12.33) was higher than their counterpart. Conclusions: The result of this study implies that children with family allergy history and passive smoking are more likely to be get asthma and wheezing than children with family allergy history and non-passive smoking. This study provide the object information to increase the efficiency of non-smoking campaign and education for decreasing pediatric asthma risk.

Effect of active smoking on asthma symptoms, pulmonary function, and BHR in adolescents

Active smoking is known to increase asthma symptoms and bronchial hyper-responsiveness (BHR) while decreasing pulmonary function in adults, but few studies have addressed these issues in adolescents. We conducted a cross-sectional survey involving questionnaires and assessment of urinary cotinine levels among 1,492 adolescents from three urban areas of South Korea. Current smoking was defined as having smoked more than 1 day in the prior 30 days or having urine cotinine levels >or=100 ng/ml. Spirometry, skin tests, and methacholine challenge tests were performed on adolescents in Seoul (n = 724). The prevalence of current smoking was 8.2% in boys and 2.4% in girls. Reports of wheeze and exercise-induced wheeze in the previous 12 months were more frequent in smokers than nonsmokers (15.2% vs. 8.5%, P = 0.024, and 20.4% vs. 10.7%, P = 0.004, respectively). In multiple logistic regression analysis, current smoking was found to be a significant risk factor for having wheezed in previous 12 months (OR = 4.5, 95% CI 1.5-13.2) and having exercise-induced wheezing in previous 12 months (OR = 8.7, 95% CI, 3.7-20.9). The subgroup analysis revealed that the FEV(1)/FVC was lower in smokers than nonsmokers (mean +/- SD, 105.1 +/- 8.6% vs. 107.8 +/- 7.8%, P = 0.019). In contrast, there was no significant difference in BHR. The effect of smoking on asthma symptoms were more pronounced in non-atopic compared with atopic adolescents. Current smoking was significantly associated with symptoms of asthma, such as having recent wheezing and recent exercise-induced wheezing, especially for non-atopics, in Korean adolescent population. Current smoking was further associated with lower pulmonary function, but not BHR.

Childhood Asthma and Increased Airway Responsiveness

Asthma is associated with increased airway responsiveness (AR), but the age when this relationship becomes established is not clear. The present study tested the hypothesis that the association between increased AR and asthma is established after 1 month of age. To relate AR in infancy to asthma in childhood. As part of a birth cohort study, AR was determined at 1 (early infancy), 6 (mid-infancy), and 12 months of age (late infancy). At 11 years of age (childhood), AR and the presence of asthma symptoms were determined. Of the 253 study subjects enrolled, AR was determined in 202 in early infancy, 174 in mid-infancy, 147 in late infancy, and 176 in childhood. Increased AR in late infancy, but not in early or mid-infancy, was associated with increased wheeze at 11 years of age (P = 0.016). Increased AR in infancy persisted into childhood in association with male gender, early respiratory illness, and maternal smoking and asthma. Among the 116 subjects assessed in late infancy and childhood, recent wheeze was present in 35% of children with increased AR at both ages, 13% with increased AR in childhood only, 12% for those with increased AR in late infancy only, and 0% for those who did not have increased AR at either age (P = 0.023); the proportions of children with diagnosed asthma in the corresponding groups were 27, 20, 12, and 0% (P = 0.038). The association between increased infantile AR and childhood asthma emerges at the end of the first year of life.