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.     

Review Article Towards a better understanding of childhood asthma

Objective: To explore the ways asthma may be defined in childhood and consider the current evidence to support these possible definitions.
Methodology The relationship of symptoms, atopy, bronchial hyperresponsiveness (BHR) and airway inflammation in defining childhood asthma is reviewed.
Results While none of the four proposed methods of defining asthma can stand alone as the 'gold standard], in childhood asthma, all four, namely clinical symptoms, atopy, BHR and airway inflammation, are intimately related. The degree of atopy and BHR, and the presence of airway inflammation, should be viewed as significant risk factors for persistent wheezing in childhood.
Conclusion At present the clinical diagnosis of asthma in childhood remains largely based on symptoms but it is likely that, with further research, the group of children who are now labelled as having asthma will be subdivided into different subgroups with implications for both treatment and outcome.     

Role of atopy in the natural history of wheeze and bronchial hyper-responsiveness in childhood

The role of atopy in the development of asthma has become increasingly recognised. We have been prospectively following a birth cohort of children of atopic parents to document the development of atopic disease. Our aim in this study was to document the natural history of BHR and wheeze at 10 years of age and to relate this to atopy. We reviewed 47 of our original cohort of 79 infants at 10 years of age and documented their clinical history of atopic disease and performed allergen skin prick tests and BHR to histamine. Thirty-three (70%) children wheezed at some time during their 10 years of life, with 13 commencing in infancy. Twenty-two children (47%) had current wheeze at 10 years of age. Wheeze in infancy was a poor predictor (RR 1.23, Cl₉₅ 0.66–2.23) of current wheeze while wheeze commencing after infancy was a good predictor (RR 2.89, Cl₉₅ 1.45–5.2). In contrast both atopy in infancy (RR 2.94, Cl₉₅ 1.92–4.53) and current atopy (RR 3.58, Cl₉₅ 1.43–9.03) were strong predictors of current wheeze. Analysis of BHR confirmed the importance of atopy in predicting its occurrence and severity. Sensitisation to D. pteronyssinus appeared to be the strongest predictor of both current wheeze and BHR. These observations confirm the importance of atopy in predicting outcome in children with asthma and suggest that wheezing in infancy and wheezing in later childhood may have different pathogenetic mechanisms.     

Nonspecific bronchial hyperresponsiveness and development of asthma in children with hay fever

It has been suggested that patients with allergic rhinitis who present nonspecific bronchial hyperresponsiveness (BHR) are those most likely to develop asthma. Therefore, a study was conducted in children with rhinoconjunctivitis to ascertain whether BHR to methacholine might predict the development of asthma in these patients. Fifteen patients with hay fever and no previous symptoms of asthma were selected. All underwent clinical symptom tests and methacholine tests, during the pollen season in the 4 consecutive years following the start of the study. At the end of this period, 5 patients had developed asthma. It may thus be affirmed that, in this group, neither the presence nor the degree of previous BHR was useful for predicting which patients would later develop asthma.     

Headache and asthma

The aim of this study was to investigate the association between headache and asthma, bronchodilators and atopy in school children. A cross-sectional survey of all primary school children was conducted in two towns near Newcastle, New South Wales, Australia; one in the vicinity of two coal-fired power stations, the other free of outdoor industrial air pollution. The main outcome measures were frequent headache, wheezing, bronchial reactivity, use of bronchodilators and atopy. Eight hundred and fifty-one primary school children aged 5-12 years participated (92% response rate). Twenty-three per cent of the children were reported to have had a history of frequent headache. Crude odds ratios indicated that the odds of frequent headache was significantly higher in children with asthma and atopy and where there was a smoker in the home, but that there was no association between frequent headache and use of bronchodilators or the sex of the child or socio-economic status measured as father's occupation. Stepwise logistic regression with frequent headache as the outcome of interest showed that, after adjusting for age and smoking in the home, the odds ratio for asthma (defined as current wheeze) was 3.24 (95% confidence interval [CI] 2.19-4.77). The similarly adjusted odds ratio for asthma defined as bronchial hyperreactivity (BHR).was 1.60 (95% Cl 1.09-2.37). Atopy was not statistically significantly associated with headache for either model. Asthma (defined as wheeze or BHR) is an independent risk factor for frequent headache. The relationship between headache and asthma is an association with bronchial hyperresponsiveness rather than atopy.     

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.     

Sex-specific trends in prevalence of childhood asthma over 30 years in Patras, Greece

Aim: According to four surveys conducted during 1978–2003, the prevalence of childhood asthma and wheezing has risen in the city of Patras, Greece, albeit at a decelerating rate. We examined sex‐specific wheeze and asthma prevalence in the same urban environment in 2008. Methods: A cross‐sectional parental questionnaire survey was performed in 2008 among third and fourth grade schoolchildren (8–9 year old), which was identical to previously conducted surveys in 1978 (n = 3003), 1991 (n = 2417), 1998 (n = 3076) and 2003 (n = 2725). Results: The prevalence of current wheeze and asthma in 1978, 1991, 1998, 2003 and 2008 (n = 2688) was 1.5%, 4.6%, 6.0%, 6.9% and 6.9%, respectively (p for trend <0.001). Respective values for lifetime (ever had) wheeze and asthma in the 1991–2008 surveys were 8.0%, 9.6%, 12.4% and 12.6% (p for trend <0.001). The male:female ratio of current and lifetime wheeze and asthma increased during the 30‐year surveillance period (p for trend <0.001). Irrespective of sex, diagnosed asthma declined among current wheezers by 17% (p < 0.001), but not among non‐current ones (6.7%, p = 0.16) during 2003–2008. Conclusions: Childhood wheeze and asthma have reached a plateau in an urban environment in Greece, while the male:female ratio increased. Asthma diagnosis declined among schoolage but not preschool wheezers during 2003–2008.     

支气管激发试验在儿童哮喘诊断和治疗中的应用

目的探讨支气管激发试验在儿童哮喘诊断和治疗中的价值及安全性。方法采用组胺支气管激发试验对103例疑诊为哮喘或哮喘缓解期患儿进行气道反应性的测定,阳性者计算其FEV1下降20%预计值时的累积吸入组胺量(PD20FEV1),并以此判定其气道高反应性(BHR)的程度。结果观察组支气管激发试验阳性62例(60.2%),其中极轻度BHR10例(16.2%),轻度34例(54.8%),中度18例(29.0%),重度0例(0%)。在试验过程中,有1例患儿出现气喘、咳嗽,2例患儿出现胸闷,4例出现刺激性咳嗽,对症处理后迅速消失。对照组30例中有2例为支气管激发试验阳性(阳性率6.7%),均为极轻度BHR,无一例出现气喘、咳嗽、胸闷、声嘶等症状。结论支气管激发试验提高了临床医生对儿童哮喘的诊断水平,并且对病情评估以及疗效的判断均具有重要价值。     

Bronchial hyper-responsiveness predicts the development of mild clinical asthma within 2 yr in school children with hay-fever

In children with mild asthma, symptoms are not always apparent. Therefore, results of tests play an important role for the diagnosis. First, to investigate whether children with bronchial hyper-responsiveness (BHR) but no symptoms of asthma in 1992 had developed clinical asthma at follow up in 1994. The second aim was to find out the diagnostic properties of tests for asthma/allergic inflammation, using either doctor diagnosed asthma (DDA), self-assessed symptoms of asthma or iso-capnic hyperventilation of cold air (IHCA), as the standard, to diagnose asthma in a group of children with hay fever. Twenty-eight children with pollinosis, 12 of them with a history of asthma for the first time during the season 1992, were studied during the birch pollen season and in the autumn of 1994. During both periods, the bronchial hyper-reactivity was estimated by methacholine bronchial provocation tests (MBPT), bronchial variability by peak expiratory flow rate variability, subjective symptoms of asthma by visual analogue scale (VAS) and bronchial inflammation by serum and urine levels of inflammatory mediators. In 1994 IHCA was added during both seasons. Eight of 16 children with BHR but without clinical asthma in 1992 had developed asthma in 1994, 14 of 16 reacted to IHCA and 13 to MBPT. All 12 children with DDA in 1992 had still asthma in 1994 and 14 children with BHR in 1992 had persistent BHR in 1994. Of 23 children with BHR in 1992, 17 had DDA in 1994 and all maintained their BHR. Furthermore, 20 of them reacted to IHCA in 1994. In 1994, 24 of 28 hay-fever children had a positive IHCA tests and 24 had positive MBPT. In relation to VAS, the sensitivity of IHCA and MBPT to predict present asthma was high, but the specificity low, whereas the specificity of most other tests was high, but based on few individuals. In relation to DDA both the IHCA test (65-80%) and the MBPT test (79-85%) had a high sensitivity and it was three to six times more likely to find a positive test among asthmatics than in non-asthmatics. Children with hay fever without clinical asthma have a high risk of developing asthma within 2 yr. In relation to DDA, inhalation of cold air and the MBPT showed a high sensitivity.     

Bronchial hyper-responsiveness in selective IgA deficiency

Secretory IgA in mucosal secretions has a broad protective function. The insufficient protection provided by the respiratory mucosa in children with selective IgA deficiency (sIgAD) might facilitate the development of bronchial hyper-responsiveness (BHR) and consequently asthma symptoms. This study was conducted to clarify the prevalence of BHR in sIgAD children and the relationship with atopic status. A cohort of 20 children (group A) aged 6.4-20.1 yr (median: 12.6) with sIgAD (serum IgA <6 mg/dl) were evaluated for BHR using inhaled hypertonic saline test as well as for atopy by skin prick testing (SPT) to eight common aero-allergens. Seventy other children with normal levels of serum IgA, but sensitized to aero-allergens (group B) and 102 with normal IgA and negative SPTs (group C) were also evaluated. Baseline spirometry demonstrated that forced vital capacity (FVC) values in group A were significantly lower than in C. Forced expiratory volume in 1 s values were similar in all groups, but impairment of the forced expiratory flow over the middle half of the FVC was detected in group B. The prevalence of BHR was similar among group A (30.0%) and group B (35.7%) (p = 0.79) but they differed from group C (5.9%) (p = 0.005). An association between BHR and reported current (p = 0.001) but not lifetime asthma symptoms among group A was also observed. There was no association between atopy and BHR in group A but only to mites' sensitization (p = 0.03). In conclusion, these results indicate that sIgAD constitutes a risk factor for development of BHR but it appears to be related to sensitization to mites.     

Inhaled corticosteroids in childhood asthma: the story continues

Inhaled corticosteroids (ICS) are the most effective anti-inflammatory drugs for the treatment of persistent asthma in children. Treatment with ICS decreases asthma mortality and morbidity, reduces symptoms, improves lung function, reduces bronchial hyperresponsiveness and reduces the number of exacerbations. The efficacy of ICS in preschool wheezing is controversial. A recent task force from the European Respiratory Society on preschool wheeze defined two different phenotypes: episodic viral wheeze, wheeze that occurs only during respiratory viral infections, and multiple-trigger wheeze, where wheeze also occurs in between viral episodes. Treatment with ICS appears to be more efficacious in the latter phenotype. Small particle ICS may offer a potential benefit in preschool children because of the favourable spray characteristics. However, the efficacy of small particle ICS in preschool children has not yet been evaluated in prospective clinical trials. The use of ICS in school children with asthma is safe with regard to systemic side effects on the hypothalamic–pituitary–adrenal axis, growth and bone metabolism, when used in low to medium doses. Although safety data in wheezing preschoolers is limited, the data are reassuring. Also for this age group, adverse events tend to be minimal when the ICS is used in appropriate doses.     

Wheezing in school children is not always asthma

Our objective was to study whether children with reported asthma differed from children with wheeze but without asthma, and from children with neither asthma nor wheeze, regarding lung function, bronchial hyper‐responsiveness (BHR) using methacholine inhalation, exercise‐induced bronchoconstriction (EIB), and skin prick test (SPT) reactivity. School children (n=2188), enrolled in a survey of asthma, were classified into three mutually exclusive groups by parental report of: asthma, wheeze, and no asthma/no wheeze. A random sample of 80 children in each group was tested (n=240). Among asthmatics, 68% (95% confidence interval (CI), 57–79) had a BHR (measured as PD₂₀ forced expiratory volume in 1 s (FEV₁) ≤ 8.16 μmol using methacholine) compared to 31% (CI 20–42%) and 30% (CI 19–40%) in the wheeze and no asthma/no wheeze groups. The dose–response slope (DRS) confirmed the PD₂₀ data and distinguished equally between groups. EIB (≥10% fall in FEV₁) was more frequent (40%, CI 29–52%) among asthmatics than among children with wheeze (12%, CI 4–19%) and no asthma/no wheeze (7%, CI 1–13%). The prevalence of at least one positive SPT was twice as high in the asthma group (58%, 47–69%) than in the wheeze (27%, CI 16–37%) and the no asthma/no wheeze (25%, 15–35%) groups. These results indicate that children with asthma differ from children with wheeze and children with no asthma/no wheeze regarding lung function, BHR, EIB, and SPT reactivity. Children with wheeze are more similar to children with no asthma/no wheeze with respect to these parameters.     

Bronchial responsiveness to methacholine and adenosine 5'-monophosphate (AMP) in young children with post-infectious bronchiolitis obliterans

Aim: Bronchial hyperresponsiveness (BHR) is a characteristic feature of asthma, but it is also frequently demonstrated by children and adults with chronic obstructive lung diseases. BHR is usually measured by bronchial challenges using direct or indirect stimuli. The aim of this study was to compare these two types of bronchial challenge in young children with post-infectious bronchiolitis obliterans (BO). Methods: Methacholine and adenosine 5'-monophosphate (AMP) bronchial challenges were performed on preschool children with post-infectious BO (n=18), those with asthma (n=23) and in controls (n=20), using a modified auscultation method. The endpoint was defined as the appearance of wheezing and/or oxygen desaturation. Results: A positive response to methacholine (an endpoint concentration ≤8 mg/ml) was observed in 88.9% (16/18) of the patients with post-infectious BO, but a positive response to AMP (an endpoint concentration ≤200 mg/ml) was observed in only 22.2% (4/18). All patients with asthma responded positively to methacholine, and most (21/23, 91.3%) of them also responded positively to AMP. The majority of the controls were insensitive to both challenges.

Conclusion: BHR to methacholine is a frequent, but by no means universal, finding in young children with post-infectious BO, but is usually not accompanied by BHR to AMP.     

Asthma, lung function and allergy in 12-year-old children with very low birth weight: A prospective study

We assessed the relationship between very low birth weight (VLBW) (≤1500 g) and the development of asthma, lung function and atopy. The study groups comprised 74 of all 86 (86%) VLBW and 64 of all 86 (74%) matched term children who were prospectively followed for 12 years. A questionnaire on asthmatic and allergic symptoms was completed and skin prick tests, spirometry and hypertonic saline provocation tests were performed at 12 years of age. Cytokine secretion was analysed in stimulated blood leukocyte cultures in 28 VLBW and 23 term children. A history of asthma was more frequent among the VLBW children, as compared with the term children at age 12 (22% vs. 9%, p = 0.046). Among the VLBW children, very preterm birth (gestational age: week 25 to 29) (RR 2.5, 95%CI 1.1–5.8), neonatal mechanical ventilation (RR 2.8, 95%CI 1.2–6.4) and neonatal oxygen supplementation (RR 4.3, 95%CI 1.3–14.0) were significantly associated with a history of asthma by the age of 12 years in univariate analyses. In multivariate logistic regression, neonatal oxygen supplementation ≥ 9 days was the only remaining significant risk factor for a history of asthma (adjusted OR 6.7, 95%CI 1.0–44). The VLBW children who required mechanical ventilation during the neonatal period were more likely to have bronchial hyperresponsiveness than those not requiring mechanical ventilation (60% vs. 28%, p = 0.050). The spirometric values were similar among the VLBW and the term children at 12 years. Very low birth weight was not significantly related to allergic rhinoconjunctivitis, eczema or positive skin prick tests. Furthermore, the levels of IL‐4, IL‐5 and IFN‐γ in stimulated cell cultures were similar in the VLBW and the term children. A history of asthma by 12 years of age was twice as common among the VLBW as the term children, and neonatal oxygen supplementation seemed to be associated with the increased risk. Furthermore, mechanical ventilation during the neonatal period was associated with bronchial hyperresponsiveness at age 12. Very low birth weight per se was not, however, related to atopy.     

Airway reactivity in parents of infants and young children with recurrent wheeze: a case-control study.

Increased airway reactivity has been found in family members of school age children and adults with asthma. As the relation between recurrent wheeze in infancy and bronchial reactivity is not yet clear, it was decided to test bronchial reactivity to methacholine in both parents of 50 preschool age children with recurrent wheeze and in 200 population based controls matched for sex, age, smoking habits, and atopy. Wheezy children fulfilled the following criteria: first attack of wheezing before the age of 2 years, at least four wheezing episodes triggered by a respiratory infection, negative skin prick tests, and no symptoms related to allergy. Four parents and five controls did not undergo the methacholine challenge because their forced expiratory volume in one second was < 80% of the predicted value. Methacholine reactivity was not significantly different in parents and controls. In summary, an increased bronchial responsiveness was not found in parents of infants and young children with recurrent wheeze triggered by infection.     

Rhinitis in 10-year-old children and early life risk factors for its development

Aim: To study the prevalence, characteristics of and risk factors for childhood rhinitis. Methods: In a whole population birth cohort study (n = 1456) the prevalence and characteristics of rhinitis among 10-y-old children were examined. At this age 1373 children (94%) completed standardized questionnaires, 1043 (72%) skin-prick testing, 953 (65%) serum inhalant immunoglobulin E antibody screening and 784 (54%) methacholine bronchial challenges. Results: At the age of 10 y the prevalence of hayfever ever was 18.6% and current nasal symptoms (rhinitis) 22.6%. Rhinitis at 10 y was largely seasonal and associated with low morbidity, although 62.7% of cases required pharmacological treatment. Atopy (positive skin test) and other allergic states were associated with rhinitis (p 3 0.001). Wheeze or diagnosed asthma was higher with coexistent rhinitis. Among wheezing children physician-diagnosed asthma (p 3 0.024) and inhaled corticosteroid use (p 3 0.001) were greater with the presence of rhinitis. Significant bronchial hyperresponsiveness (methacholine concentration giving a 20% fall in forced expiratory volume in 1 s 34.0 mg ml 31 ) was greater if rhinitis was present even when the child did not wheeze (p 3 0.001). Risk factor analysis for rhinitis identified the independent significance for atopy (p 3 0.001) and eczema ( p = 0.009) at the age of 4 y plus paternal rhinitis (p 3 0.001), maternal rhinitis ( p = 0.033) and maternal food allergy ( p = 0.016). Conclusion: Rhinitis is common at the age of 10 y, with strong associations with atopy, wheezing, asthma and bronchial hyperresponsiveness. An inherited predisposition towards atopy appears to predominate over environment in the aetiology of this state.     

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.     

缓解期哮喘患儿的支气管反应性与小气道功能的关系

目的　测定缓解期哮喘患儿支气管反应性及小气道功能 ,探讨支气管反应性与小气道功能及临床缓解时间的关系。方法　对 39例缓解期哮喘患儿进行支气管激发试验 ,用传统方法测定肺通气功能。比较最大呼气中段流量 (maximalmid expiratoryflow ,MMEF) <80 %患儿和MMEF≥80 %患儿的支气管激发试验阳性率 ,以及临床缓解时间≤ 12个月和 >12个月的患儿支气管激发试验阳性率。结果　缓解期哮喘患儿 39例中 2 8例 (72 % )支气管激发试验阳性 ;15例 (38% )MMEF <80 %。在MMEF <80 %患儿和MMEF≥ 80 %患儿之间支气管激发试验阳性率差异无显著意义 (P >0 0 5 )。缓解时间≤ 12个月和 >12个月的患儿间支气管激发试验阳性率差异无显著意义 (P >0 0 5 )。结论　缓解期哮喘患儿仍然存在支气管高反应性及小气道阻塞 ,提示缓解期气道炎症仍持续存在 ;症状缓解时间超过 1年者支气管激发试验阳性率较缓解时间 1年之内者无明显改善。     

Prevalence, severity and determinants of asthma in Danish five-year-olds

BACKGROUND: The prevalence of asthma and wheeze is increasing. AIM: To study the annual and cumulative prevalence of asthma and wheeze in 5-y-old Danish children. METHODS: We obtained data on 3052 (82.0% of eligible) Danish children by a postal parental questionnaire including ISAAC questions regarding respiratory symptoms and our own questions on sociodemography and tobacco exposure. RESULTS: "Wheeze ever" was reported in 38.3%, "doctor-diagnosed asthma ever" in 10.5%, "childhood bronchitis ever" in 30.0%, "current wheeze" (<12 mo) in 19.7%, and being "severe" (>3 episodes) in 3.9% of the children. Current wheeze was associated with male gender (OR 1.63, 95% CI 1.35-1.96), low parental post-primary education (OR 1.29, 95% CI 1.02-1.63 for <3 y vs > or =3 y) and current maternal smoking (OR 1.69, 95% CI 1.39-2.04). "Severe current wheeze" was recognized as asthma in six and childhood bronchitis in three of 10 cases. Nearly all diagnosed asthmatics had suffered wheeze, two-thirds recently. CONCLUSION: We found a high prevalence of asthma and wheeze in Danish late-preschool children, associated with male gender, current maternal tobacco smoking and low parental post-primary education. The majority of children with current wheeze had an early onset, and severe early symptoms tended to persist. Used with consideration, the label "childhood bronchitis" seems purposeful.     

乌鲁木齐地区喘息患儿发生支气管哮喘的危险因素

目的 探讨乌鲁木齐地区喘息患儿发生支气管哮喘(哮喘)的危险因素.方法 对2008年1 -12月在新疆医科大学第五附属医院门诊及住院的300例喘息患儿的临床资料进行统计.用统一的调查表调查其年龄、性别、湿疹、变应性鼻炎、食物过敏、家族过敏史/哮喘史、运动相关性喘息等.出院后通过门诊或电话进行随访.采用 Logistic回归分析方法对各因素与哮喘发生的关系及相关程度进行分析.结果 随访2a,275例获得随访;25例失访.275例喘息患儿在随访期内86例(31.2％)发生哮喘.Logistic回归分析发现湿疹、变应性鼻炎、家族过敏史/哮喘史、运动相关性喘息、反复下呼吸道感染( LRTI)、外周血嗜酸性粒细胞(EOS)增高与喘息患儿发生哮喘有关(湿疹:OR=2.376,95％ CI0.098～0.935,P=0.039;变应性鼻炎:OR=1.052,95％ CI2.267 ～14.283,P =0.024;家族过敏史/哮喘史:OR=1.886,95％CI1.004～3.542,P =0.048;运动相关性喘息:OR=1.881,95％ CI2.267 ～18.983,P =0.001;LRTI:OR=5.341,95％ CI1.676～ 10.983,P =0.016;外周血EOS增高:OR=3.915,95％ CI1.459～ 10.501,P=0.002).结论 个人过敏史(湿疹和变应性鼻炎)、家族过敏史/哮喘史、运动相关性喘息、LRTI、外周血EOS增高是乌鲁木齐地区喘息患儿发生哮喘的危险因素.