Non-atopic asthma in children is related to maternal bronchial hyperreactivity

Data on the pathogenic mechanisms underlying the development of non-atopic asthma in children are scarce. Our aim was to evaluate the association and compare the atopic status, pulmonary functions, bronchial hyperresponsiveness and serum total immunoglobulin E (IgE) levels of parents of atopic and non-atopic asthmatic children by using objective methods. Fifty-one asthmatic children aged 4–16 yr and their parents were included into the study. Initially the American Thoracic Society's Respiratory Disease questionnaire inquiring data on symptoms of asthma, rhinitis and past medical history was filled in. Afterwards, skin prick test with aeroallergens, pulmonary function and methacholine bronchial provocation tests and serum sampling for total IgE level determinations were carried out. Bronchial hyperresponsiveness to methacholine was significantly more common in the mothers of non-atopic children compared to those of atopic ones, although no significant difference was observed in the skin prick test reactivity, pulmonary function test parameters and serum IgE levels. Questionnaire data revealed that the presence of asthmatic symptoms such as wheezing and phlegm and doctor-diagnosed asthma were more common in the mothers of non-atopic children. Meanwhile, asthmatic symptoms were also found to be significantly more common in fathers of non-atopic children. Logistic regression analyses revealed that maternal PC₂₀ was the only predictive factor for the risk of displaying non-allergic asthma in children. The results demonstrate that among the risk factors studied, maternal bronchial hyperreactivity was associated with the development of asthma in non-atopic children.     

Epidemiologic characteristics of rhinitis in Turkish Children: the International Study of Asthma and Allergies in Childhood (ISAAC) phase 2

Rhinitis is a common problem with important comorbidities. In order to search the association between rhinitis, allergic phenotypes and other risk factors in Turkish children, a parental questionnaire about allergic diseases and risk factors, and skin prick test (SPT) with 13 inhalant allergens were performed in a population-based sample of 2774 children aged 9-11 yr. Bronchoprovocation testing with hypertonic saline (HS)and total IgE analysis were limited to a subsample of 350 children. Rhinitis was defined as a problem with sneezing, rhinorrhea, or nasal congestion when the child did not have a viral respiratory infection. The prevalences of ever rhinitis, current (last 12 months) rhinitis (CR), and ever hay fever were 36.3%, 30.6%, and 8.3%, respectively. SPT positivity rate was 20.4% among children with CR. Current wheezing and flexural dermatitis were significantly associated with CR. CR significantly increased the risk of asthma among both atopic and non-atopic subjects [odds ratio (OR), 3.98; 95% CI, 1.81-8.76; and OR, 2.79; 95% CI, 1.82-4.26, respectively]. The association between CR and bronchial hyperreactivity (BHR) was not significant. The multiple logistic regression analysis revealed family atopy (OR=2.25, 95% CI=1.79-2.83, p<0.001), current indoor heating with gas stove (OR=1.78, 95% CI=1.18-2.64, p=0.006) and dampness/molds at home during the first year of life (OR=1.70, 95% CI=1.25-2.31, p=0.001) as significant risk factors for CR. Turkish school children showed a high prevalence of rhinitis with a preponderance of non-atopics. The highly significant association between rhinitis and asthma independent of atopic sensitization emphasize the importance of non-atopic forms of rhinitis.     

Airway infections in infancy and the presence of allergy and asthma in school age children.

AIM: To investigate the association between a history of otitis media and respiratory tract infections in infancy and allergic sensitisation and asthma in school age children of atopic and non-atopic parents. METHODS: Based on a survey of 4585 schoolchildren, three groups of children aged 6-16 years were selected, of whom 502 were eligible with complete data: (1) diagnosed asthma (n = 166); (2) wheeze within past 12 months (n = 155); and (3) no asthma/no wheeze (n = 181). This study population was further analyzed by subgroups of children with or without parental atopy. Main outcome measures were allergic sensitisation verified by skin prick test and asthma. RESULTS: Children of atopic parents had a reduced risk of developing allergic sensitisation in school age if they had a combined history of both otitis media and lower respiratory tract infections during infancy (adjusted odds ratio (aOR) 0.13, 95% CI 0.03 to 0.50) or a history of otitis media (aOR 0.31, 95% CI 0.12 to 0.83). A history of lower respiratory tract infections in infancy increased the risk of asthma in children of non-atopic parents (aOR 4.21, 95% CI 1.68 to 10.57). CONCLUSION: In the present study population, a history of otitis media in infancy seems to be negatively associated with allergic sensitisation in school age children of atopic parents, whereas a history of lower respiratory tract infections was positively associated with asthma in children of non-atopic parents.     

Wheezing requiring hospitalization in early childhood: Predictive factors for asthma in a six-year follow-up

Although asthma is common after wheezing in early childhood, the risk factors for and the prevention of later asthma are poorly understood. During the present follow-up study, a range of possible predictive factors for school-age asthma was evaluated. The study group consisted of 82 children hospitalized for wheezing at age < 2 years in 1992–93. The baseline data were collected on entry to the study. In 1999, the children were re-examined at the median age of 7.2 years. A structured questionnaire was applied to chart the symptoms suggestive of asthma, and the children were examined clinically. An exercise challenge test, as well as skin prick tests (SPT) to common inhalant allergens, was performed. Asthma was present in 33 (40%) children, 30 (91%) having continuous medication for asthma. The significant asthma-predictive factors, present on entry to the study, were blood eosinophilia (p = 0.0008), atopic dermatitis (p = 0.0089), elevated total serum immunoglobulin E (IgE) (p = 0.0452), and a history of earlier episodes of wheezing in infancy (p = 0.0468). SPT positivity in early childhood was also associated with school-age asthma (p = 0.002). In contrast, respiratory syncytial virus (RSV) identification during the index episode of wheezing played a minor role as a predictive factor for asthma. In conclusion, if hospitalization for wheezing occurs in infancy, more than every third child will suffer from asthma at early school age; the risk is significantly increased with recurrent wheezing in infancy and the development of allergic manifestations.     

Airway infections in infancy and the presence of allergy and asthma in school age children

Aim: To investigate the association between a history of otitis media and respiratory tract infections in infancy and allergic sensitisation and asthma in school age children of atopic and non-atopic parents. Methods: Based on a survey of 4585 schoolchildren, three groups of children aged 6–16 years were selected, of whom 502 were eligible with complete data: (1) diagnosed asthma (n = 166); (2) wheeze within past 12 months (n = 155); and (3) no asthma/no wheeze (n = 181). This study population was further analyzed by subgroups of children with or without parental atopy. Main outcome measures were allergic sensitisation verified by skin prick test and asthma. Results: Children of atopic parents had a reduced risk of developing allergic sensitisation in school age if they had a combined history of both otitis media and lower respiratory tract infections during infancy (adjusted odds ratio (aOR) 0.13, 95% CI 0.03 to 0.50) or a history of otitis media (aOR 0.31, 95% CI 0.12 to 0.83). A history of lower respiratory tract infections in infancy increased the risk of asthma in children of non-atopic parents (aOR 4.21, 95% CI 1.68 to 10.57). Conclusion: In the present study population, a history of otitis media in infancy seems to be negatively associated with allergic sensitisation in school age children of atopic parents, whereas a history of lower respiratory tract infections was positively associated with asthma in children of non-atopic parents.     

Bronchial asthma after early childhood wheezing: a follow-up until 4.5–6 years of age

Over a period of 12 months from 1981 to 1982, 83 patients aged less than 2 years were treated in hospital for acute bronchiolitis. The children were followed-up prospectively; 68 (83%) completed the study until 4.5–6.0 years of age. At this age, 17 (25%) of the 68 children with bronchiolitis still suffered from wheezing attacks. These 17 asthmatics suffered from both atopic dermatitis (29 versus 6%) and allergic rhinitis (29 versus 8%) more frequently than non-asthmatic children. In contrast, positive results in the skin prick tests were almost equally common (29 and 20%) in asthmatic and non-asthmatic children. In these tests, allergies to birch pollen, timothy grass pollen and house dust mite were most common; asthma was particularly associated with house dust mite allergy. The presence of atopic dermatitis, elevated immunoglobulin E values and repeated wheezing episodes between I and 2 years of age were significant risk factors for later asthma. In conclusion, the risk for later asthma is increased after early childhood bronchiolitis; the frequency of asthma was 25% in the present study. Our results confirm that atopics are at a greater risk of developing asthma later in childhood than non-atopics; the risk was significant from 1 year of age onwards.     

Hypertonic saline challenge tests in the diagnosis of bronchial hyperresponsiveness and asthma in children

The hypertonic saline challenge test is the recommended method to assess bronchial hyperresponsiveness in the International Study of Asthma and Allergies in Childhood (ISAAC). The sensitivity of this procedure to assess asthma symptoms, however, has been reported to vary among study centers. The purpose of our study was to evaluate the value of this provocation test in an epidemiological survey in children, and to relate the degree of bronchial hyperresponsiveness to the severity of asthma symptoms. All 11–13‐year‐old children from 16 randomly selected schools in Linköping, Sweden received a questionnaire regarding respiratory symptoms and allergic disease. Skin prick tests with eight inhalant allergens were performed. In addition, all children with wheeze over the past 12 months (current wheeze) and a random sample of children without current wheeze were invited to perform hypertonic saline provocation tests. A complete data set was available for 170 children, including 50 with and 120 without current wheeze. Bronchial hyperresponsiveness (BHR) was defined as at least 15% decline in FEV₁. The degree of BHR was represented by the response/dose ratio, i.e. the fall in FEV₁ divided by total dose of inhaled saline. The severity of asthma symptoms was classified by the number of wheezing episodes over the past 12 months. ‘Asthma ever’ was defined by a combination of symptoms in the questionnaires. Children with ‘asthma ever’ and current wheeze were considered as having current asthma. Current atopic asthma was defined as current asthma with at least one positive skin prick test. The sensitivity of the procedure to detect ‘asthma ever’, current asthma and current atopic asthma was 62, 61 and 83%, and the specificity 83, 81 and 60%, respectively. The positive challenge rate was 52, 34, 13 and 7% among current wheezers, previous wheezers, non‐wheezers with a history of allergy and healthy children. The degree of bronchial hyperresponsiveness increased with the number of wheezing episodes. Thus, the median and range of the response/dose ratio were 4.8%/ml (2.1–14.8), 2.6%/ml (0.7–8.6) and 1.3%/ml (0.8–2.7), respectively, for children with ≥ 4 episodes, 1–3 episodes and no wheezing episodes over the past 12 months (p<0.001). In conclusion, hypertonic saline provocation test is useful as a tool to detect asthma in epidemiological studies in children. The degree of bronchial hyperresponsiveness, as represented by the response/dose ratio, reflects the severity of asthma symptoms.     

Clara细胞分泌蛋白10基因G38A多态性与5岁以下喘息患儿的相关性

目的探讨5岁以下喘息患儿Clara细胞分泌蛋白10(CC10)基因G38A位点多态性与喘息发病机制的关系。方法随机选取于本院就诊的5岁以下反复喘息患儿120例,分为有特应质高危因素的喘息Ⅰ组(n=67)(湿疹45例,父母或父母一方有哮喘病史13例,变应性鼻炎5例,变应性皮炎4例)和无特应质高危因素的喘息Ⅱ组(n=53);对照组为本院外科近期无感染疾病史、择期进行手术的术前患儿(n=55)。采用PCR-限制性片段长度多态性分析对喘息组和对照组患儿CC10 G38A位点基因型频率和等位基因频率进行检测,比较3组间CC10 G38A位点基因型频率和等位基因频率。结果喘息Ⅰ组、喘息Ⅱ组和对照组3种基因型AA、GA、GG分布频率分别为20.9%、44.8%、34.3%,9.4%、32.1%、58.5%、9.1%、31.0%、60.0%;喘息Ⅰ组和喘息Ⅱ组CC10基因G38A位点基因型频率比较差异有统计学意义(P<0.05);喘息Ⅰ组和对照组CC10基因G38A位点基因型频率比较差异亦具有统计学意义(P<0.05)。喘息Ⅰ组、喘息Ⅱ组和对照组38A和38G等位基因频率分别为43.3%、56.7%,25.5%、74.5%,24.5%、75.5%;喘息Ⅰ组和喘息Ⅱ组、喘息Ⅰ组和对照组比较差异均有统计学意义(Pa<0.05)。结论喘息患儿与哮喘存在相同的基因分布频率,发生哮喘的危险性高;对于CC10基因具有A等位基因的喘息患儿应密切关注。     

Sodium cromoglycate therapy in wheezing infants: preliminary evidence of beneficial outcome at early school age

BACKGROUND: In order to affect the natural course of childhood wheezing and asthma, anti-inflammatory therapy is often prescribed for young wheezing children, but there is lack of long-term follow-up data. METHODS: Eighty-two of the original 100 children, hospitalized for wheezing under the age of 2 years in 1992-1993, were re-examined at school age in 1999. The children had participated in an open, randomized, parallel-group trial including a 4-month intervention with inhaled sodium cromoglycate (SCG) or budesonide (BUD). The baseline data, including data on atopy, eosinophilia and viral etiology, were prospectively collected on admission. RESULTS: At early school age (median 7.2 years), asthma was present in 33 (40%) children. There was less asthma in the original SCG (21%) than in the control group (54%) (OR 0.23; 95% CI 0.07-0.77). The figure was 46% in the BUD group. When the analyses were performed separately for atopic and non-atopic infants, the difference was significant only among atopics. The lowered risk for asthma in the SCG group remained significant in the multivariate logistic regression analysis when adjusted for age, sex and atopy, and further when adjusted for earlier episodes of wheezing and respiratory syncytial virus identification. However, after adjustment for blood eosinophilia, the significance was lost, albeit the risk for asthma remained low (OR 0.21; 95% CI 0.04-1.12). A sensitivity analysis, which was done by including the six drop-outs of the SCG group as unfavorable and the 12 drop-outs of other groups as favorable outcomes in the model, did not change the direction of the result (OR 0.70; 95% CI 0.26-1.89). CONCLUSIONS: An early SCG intervention in infants hospitalized for wheezing was associated with a lowered risk for early school-age asthma, especially in infants with evidence of atopy.     

High body mass index, asthma and allergy in Swedish schoolchildren participating in the International Study of Asthma and Allergies in Childhood: Phase II

AIM: To assess the relationship between high body mass index (BMI) and asthma and atopic manifestations in 12-y-old children. METHODS: The relationship between high BMI and asthma symptoms was studied in 457 sixth-grade children, with (n = 161) and without (n = 296) current wheeze. High BMI was defined as > or = 75th percentile of gender-specific BMI reference values for Swedish children at 12 y of age; overweight as a subgroup of high BMI was defined as > or = 95th percentile. Children with a BMI < 75th percentile served as controls. Questionnaires were used to assess asthmatic and allergic symptoms, and bronchial hyperresponsiveness was assessed by hypertonic saline provocation tests. RESULTS: Current wheeze was associated with high BMI after adjustment for confounding factors (adjusted OR 1.7, 95% CI 1.0-2.5) and overweight had an even more pronounced effect (adjusted OR 1.9, 95% CI 1.0-3.6). In addition, asthma severity was associated with high BMI, as evaluated by the number of wheezing episodes during the previous 12 mo among the wheezing children (adjusted OR 2.0, 95% CI 1.0-4.0). There was also an association between high BMI and the presence of eczema in wheezing children (adjusted OR 2.2, 95% CI 1.0-4.6). However, high BMI was not significantly associated with hay fever, positive skin prick tests or bronchial hyperresponsiveness. CONCLUSION: The study confirms and extends a previously observed relationship between BMI and the presence of wheezing and asthma.     

具有喘息症状或过敏性疾病的年幼儿皮肤点刺试验结果分析

目的：通过分析0~5岁儿童变应原皮肤点刺试验结果,了解具有喘息症状的可疑哮喘及过敏性疾病症状的患儿对吸入变应原过敏反应的特点,为儿童哮喘及过敏性疾病的早期诊断提供依据。方法：选择2010年9月1日至12月31日长沙市某社区0~5岁具有喘息症状或过敏性疾病症状的患儿共102例为变应原筛查组;对照组选择同年龄组无喘息及过敏性疾病史的儿童94例。两组均进行变应原皮肤点刺试验。结果：变应原筛查组皮肤点刺试验阳性率61.8%（63/102）明显高于对照组的9.6%（9/94）,差异有统计学意义（P<0.05）;反复喘息合并过敏性鼻炎者的皮肤点刺试验阳性率明显高于单纯喘息组（P<0.05）;喘息次数与皮肤点刺试验阳性率呈正相关（r=0.91,P<0.05）;对螨虫的皮肤点刺试验阳性率（24.2%）明显高于其他过敏原（3.5%）,差异有统计学意义（P<0.05）;粉尘螨的皮肤点刺阳性率（50.0%）明显高于屋尘螨（14.7%）,差异有统计学意义（P<0.05）。结论：早期儿童喘息可能是发生过敏性哮喘的重要因素;变应原皮肤点刺试验是诊断过敏性疾病的重要依据,并有助于评估喘息患儿对吸入性变应原的过敏反应特点。     

The impact of early lifestyle factors on wheezing and asthma in Austrian preschool children

AIM: This study investigated the influence of early lifestyle factors on the prevalence of asthma and wheezing in preschool children in Tyrol, Austria. METHODS: A cross-sectional questionnaire survey was performed in 1761 preschool children to obtain information on wheezing and asthma in the light of early lifestyle factors. RESULTS: Factors independently associated with an increased risk for wheezing in the past 12 months included high parental education (OR: 1.5, 95% CI: 1.1-2.1) and parental hay fever (OR: 1.5, 95%CI: 1.1-2.2). Risk factors for doctor-diagnosed asthma (DDA) were early pet contact (OR: 2.2, 95% CI: 1.1-4.8) and parental asthma (OR: 3.0, 95%CI: 1.0-9.1), whereas breastfeeding decreased the risk (OR: 0.5, 95% CI: 0.2-1.0). Boiling the pacifier/sucker daily increased the risk for wheezing in the past 12 months (OR: 1.4, 95%CI: 1.0-2.0) and revealed a tendency towards DDA (OR: 1.9, 95% CI: 0.9-4.0). CONCLUSION: In preschool children, we established an independent association between wheezing in the past 12 months, DDA and boiling frequency of the pacifier/bottle sucker during infancy. The impact of pacifier boiling frequency on atopic diseases on the basis of the hygiene hypothesis needs further investigation.     

Asthma phenotypes in childhood: lessons from an epidemiological approach

Asthma is a heterogenous disease with variable signs and symptoms among patients. It also presents significant individual variability over time. Recently, some important population-based studies that followed children from birth or from early childhood into adulthood have shed new light on how we understand this syndrome. Three phenotypes have been identified in children with asthma: transient wheezing, non-atopic wheezing of the toddler and pre-school-aged child and IgE-mediated wheezing. Transient wheezing is associated with symptoms that are limited to the first 3-5 years of life, decreased lung function, maternal smoking during pregnancy and exposure to other siblings or children at daycare centres. There is no association between transient wheezing and family history of asthma or allergic sensitisation. Children wheezing with respiratory syncytial virus in the first years of life are more likely to be wheezing up to 13 years of age; this is independent of atopy (non-atopic wheezers) and is not related to atopic sensitisation. Wheezing associated with evidence of allergic sensitisation has been identified as the 'classic' asthma phenotype. Early allergic sensitisation is a major risk factor for persistent asthma.     

Prevalence of bronchial hyperreactivity asd etermined by several methods among Estonian schoolchildren

There is a lack of established criteria to identify asthma and bronchial hyerreactivity (BHR) in epidemiological studies, although both conditions appear to bear some relationship to atopy, at least in children. Recent studies indicate a low prevalence of atopy in former Socialist countries in Europe, yet the prevalence of BHR has been reported to be high. We have analysed the relationship between the outcome of various lung function tests, atopy and clinical symptoms of bronchial asthma in an epidemiological survey of Estonian 10-12 year old schoolchildren. Metacholine provocation test (four steps with the cumulative doses 100, 300, 700 and 1100uμg), exercise challenge test and PEF-variability over two weeks were done in 806 children in Tallinn (coastal, industrialised city) and 774 children in Tartu (inland, uniersity town). A positive response to the metacholine challenge test was recorded in 19% in Tallinn and in 32% in Tartu (p < 0.001). A similar tendency was observed for a more than 15% decrease of FEV¹ in the exercise challenge test, i. e. 6% in Tallinn and 18% in Tartu. There was only a weak relationship between BHR, as defined by either a positive metacholine challenge and/or exercise test, diagnosed asthma and reported wheezing. Thus, 47% of the wheezing children and 30% of the children with asthma had negative test results. Only 17% of the children with a positive metacholine challenge were atopic, as defined by at least one positive skin prick test. In conclusion, none of the methods employed to assess bronchial hyperre-sponsiveness were very useful for the identification of wheezing and asthmatic children in this epidemiological study. In contrast to the results of studies in Western Europe, most children with bronchial hyperreactivity in Estonia are not atopic.     

Prevalence of asthma-associated symptoms in Turkish children

The aim of the first national cross-sectional survey was to determine the prevalence of asthma-like respiratory symptoms and the associated risk factors among children aged 0-17 via interview with the parents by primary care physicians. They were selected through stratified two-stage cluster probability sampling in urban and rural parts of randomly selected 27 of 81 administrative districts in Turkey. Data was collected for 46,813 children (23,512 males and 23,301 females) of whom 66 percent resided in urban areas. The prevalence of physician-diagnosed asthma was 0.7 percent. The lifetime and current (last 12 months) prevalences were 14.7 percent and 2.8 percent for asthma, and 15.1 percent and 3.4 percent for wheezing respectively. The presence of personal atopy and history of family atopy were the most significant risk factors for current prevalences of wheezing, and asthma [adjusted Odds ratios (OR) and 95% confidence intervals (CI) were 6.2 (CI=4.0-9.5) and 1.8 (CI=1.3-2.4) for wheezing, and 8.5 (CI=5.6-12.9) and 1.9 (CI=1.4-2.5) for asthma, respectively]. Though there were no significant differences among those residing in urban versus rural areas regarding the current prevalences of asthma and wheezing, those living in coastal areas had considerably higher current prevalences than those inland (OR=2.6, CI=1.9-3.5 for wheezing, and OR=2.3, CI=1.7-3.1 for asthma). Residence in northern Turkey appeared to be a significant risk factor for wheezing (OR=1.9, CI=1.4-2.5), and children resident in southern Turkey exhibited the highest risk for occurrence of asthma (OR=1.5, CI=1.1-2.0) compared with eastern Turkey. In conclusion, the respiratory symptoms associated with asthma were an important cause of morbidity in childhood in Turkey. The discrepancy between prevalence of physician-diagnosed asthma and lifetime and/or current asthma prevalence figures may reflect the reluctancy of both physicians and parents to diagnose this condition. Besides strongest associations with personal atopy and atopic heredity, there were significant differences in prevalence rates between children residing in different regions, supporting the role of environmental factors.     

Prevalence of fatty liver in non-obese Japanese children with atopic dermatitis

Fatty liver in non-obese Japanese children was observed in 3.2% of non-atopic children and in 17.6% of patients with atopic dermatitis in 2000. The prevalence of fatty liver in non-obese children aged 0-12 years was studied from 2001 to 2003. Subjects were either non-atopic children, or suffering from bronchial asthma, allergic rhinitis, or atopic dermatitis. Fatty liver was studied by abdominal ultrasound scans. The prevalence of fatty liver was increasing annually, and it reached to 12.5% in non-atopic children, 13.1% in patients with bronchial asthma, 13.7% in patients with allergic rhinitis, or 33.9% in patients with atopic dermatitis, in 2003. Since fatty liver in childhood may be a risk factor for lifestyle-related diseases in future, care should be taken to prevent it.     

Use of Phadiatop® Infant in diagnosis of specific sensitization in young children with wheeze or eczema

Wheezing and eczema are common symptoms in young children and it is important to disclose sensitization for correct management. The objective of this study was to assess the diagnostic values of Phadiatop Infant, an in vitro test for graded determination of immunoglobulin E (IgE) antibodies to food and inhalant allergens. One-hundred and forty-nine children (median age 1.4 yr) with symptoms of wheezing (51%) eczema (28%) or a combination of both (21%) were classified as atopic or non-atopic based on case history, atopic history, physical examination and determination of IgE antibodies. The clinical performance of Phadiatop Infant was evaluated for 145 children against this classification in a blinded manner to the allergist. Fifty-one children were classified as atopic of which Phadiatop Infant identified 49. Ninety-four were non-atopic of which the test identified 90. This resulted in a sensitivity of 96%, a specificity of 96%, a positive and a negative predictive value of 94% and 98%, respectively. Logistic regression showed that probability had to be assessed as atopic increased with increasing Phadiatop Infant values. These results suggest that Phadiatop Infant can be recommended as an adjunct to the clinical information in the differential diagnosis on IgE-mediated allergy in young children. The test thus provides an opportunity for early correct diagnosis and identification of subjects at risk for whom intervention may be necessary.     

Teenage asthma after severe infantile bronchiolitis or pneumonia

OBJECTIVE: The purpose of the study was to evaluate asthma at >13 y of age in children with infantile bronchiolitis or pneumonia. METHODS: In 1981-1982, 127 children at <2 y of age were hospitalized for bronchiolitis (n = 81) or pneumonia (n = 46). Respiratory syncytial virus (RSV) infection, eosinophilia and markers of atopy were assessed and recorded on admission. At a median age of 14.9 y, atopic and asthmatic symptoms were screened by a written questionnaire in 98/127 (77%) study subjects. RESULTS: Asthma was present, according to two definitions, in 14% to 23% in the original bronchiolitis and in 12% to 15% in the original pneumonia group. The figures were 8% to 17% in the RSV infection and 16% to 23% in the non-RSV infection group. Early asthma-predictive factors were repeated wheezing, atopic dermatitis and elevated blood eosinophils. All but one of the teenage asthmatics had allergic rhinitis. CONCLUSION: An increased risk for asthma persists until the teenage period after bronchiolitis and pneumonia in infancy. Both early and later atopy were significant risk factors. The present study was unable to demonstrate the association between early RSV infection and teenage asthma.     

Asthma attributable to atopy: does it depend on the allergen supply?

The use of the population attributable fraction (PAF) of asthma owing to atopy has not been widely used in epidemiological studies on childhood asthma, especially to compare regions of the same country. The present study includes 1039 children from Cartagena, Spain (Mediterranean coast) and 663 from Madrid (centre of Spanish plateau) using the ISAAC phase II methodology (questionnaire and prick test to the most common allergens). While there were no differences in asthma symptoms between school children (aged 10-11 yr) from Madrid and Cartagena, atopy to any allergen was significantly higher in those from Madrid (40.9% vs. 29.3%, respectively, p < 0.0001). However, children from Madrid were mainly positive to pollen allergy whereas those from Cartagena were positive for mite allergy. PAF of all the different asthma symptoms owing to atopy (any positive skin test) and PAF of current wheezing owing to a more severe atopy (three positive wheals) were higher in children from Cartagena than those from Madrid (45.5% vs. 28.6% and 14.2% vs. 6.2%, respectively). Per cent of previous year wheezing attributable to atopy to specific allergens varied among those cities and was higher for D. pteronissinus, D. farinae, cat, and olive tree in children from Cartagena, and--conversely--higher for mixed grasses, mixed trees and Alternaria in those from Madrid. All of these differences remained significant even after adjusting for risk factors. PAF for asthma owing to atopy could be very different within the same country, probably depending on the allergen supply which may depend on environmental factors such as the climate.     

Prevalence and risk factors of allergies in Turkey: Results of a multicentric cross-sectional study in children

The Prevalence And Risk Factors of Allergies in Turkey (PARFAIT) study was planned to evaluate prevalence and risk factors of asthma and allergic diseases and also to find out which geographical variables and/or climatic conditions play a role determining the prevalence of allergic diseases in Turkish school children. Study was planned as cross-sectional questionnaire-based. About 25,843 questionnaires from 14 centers were appropriate for analysis. Parental history of allergy, having an atopic sibling and other atopic disease in index case was significant risk factors for all allergic diseases. Breast feeding decreased the risk of current asthma (OR: 0.92, CI: 0.86-0.99) and wheezing (OR: 0.93, CI: 0.87-0.99) but not allergic rhinitis and eczema. Respiratory infection in the past was an important risk factor for the occurrence of allergic diseases especially for asthma which was increased 4.53-fold. Children exposed to household smoke were significantly at higher risk of asthma, wheezing, and allergic rhinitis (OR: 1.20, CI: 1.08-1.33; OR: 1.21, CI: 1.09-1.34; and OR: 1.32, CI: 1.21-1.43, respectively). All allergic diseases were increased in those children living in areas which have altitude of below 1000 m and mean yearly atmospheric pressure above 1000 mb. The study has suggested that household and country-specific environmental factors are associated with asthma, wheezing, allergic rhinitis, and eczema risk during childhood in Turkey.