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.     

Asthma and lung function 20 years after wheezing in infancy: results from a prospective follow-up study

OBJECTIVE: To determine the outcome until adulthood after wheezing in infancy, compared with pneumonia in infancy and with controls. DESIGN: An 18- to-20-year prospective cohort study. SETTING: Pediatric department at a university hospital, providing primary hospital care for a defined population.Patients Fifty-four children hospitalized for bronchiolitis and 34 for pneumonia at younger than 2 years, and 45 controls with no early-life wheezing or hospitalization, were studied at median age 19 years. MAIN OUTCOME MEASURES: A questionnaire on asthma symptoms and medication, physical examination, flow volume spirometry (FVS), methacholine inhalation challenge (MIC), home peak expiratory flow (PEF) monitoring, and skin prick testing (SPT) to common inhalant allergens. The 2 asthma definitions were physician-diagnosed asthma and previously diagnosed asthma with recent asthmatic symptoms (physician-diagnosed asthma included). RESULTS: By the 2 definitions, asthma was present in 30% (odds ratio [OR], 3.37; 95% confidence interval [CI], 1.12-10.10) and in 41% (OR 1.38; 95% CI, 0.37-5.21) in the bronchiolitis group, in 15% (OR, 5.50; 95% CI, 1.87-16.14) and in 24% (OR, 2.07; 95% CI, 0.59-7.22) in the pneumonia group, and in 11% in the control group. After bronchiolitis, the FVS values were forced vital capacity (FVC), 108% (SD, 13%) of predicted; forced expiratory volume in 1 second, 98% (SD, 12%); forced expiratory volume in 1 second divided by FVC, 91% (SD, 7.6%); midexpiratory flow at 50% of the FVC, 74% (SD, 19%); and midexpiratory flow at 25% of the FVC, 74% (SD, 22%). Bronchial reactivity by MIC was present in 25 (48%) of 52 subjects in the bronchiolitis group, in 13 (42%) of 31 in the pneumonia group, and in 14 (32%) of 44 in the control group. The prevalence of atopy (positive SPTs) was 48% to 63% in the 3 groups. In a logistic regression adjusted for atopy and smoking, infantile bronchiolitis was an independent risk factor for asthma by both definitions. CONCLUSION: The increased risk for asthma persists until adulthood after bronchiolitis in infancy.     

Risk factors associated with wheezing in infants

Objectiveto identify possible risk factors associated with wheezing in infants (12-15 months-old) in the state of Mato Grosso, Brazil.Methodsthis was a cross-sectional study performed by applying a standardized written questionnaire from the international study on wheezing in infants (Estudio Internacional de Sibilancia en Lactantes - EISL), phase 3. Parents and/or guardians of infants were interviewed at primary health care clinics or at home from August of 2009 to November of 2010. Factors associated to wheezing were studied using bivariate and multivariate analysis (using the Statistical Package for Social Sciences [SPSS] v.18.0), and expressed as odds ratios (OR) and 95% confidence intervals (95% CI).Resultsthe written questionnaire was answered by 1,060 parents and/or guardians. The risk factors for wheezing were: history of asthma in the family [mother (OR = 1.62; 95% CI = 1.07-2.43); father (OR = 1.98; 95% CI = 1.22-3.23); siblings (OR = 2.13; 95% CI = 1.18-3.87)]; history of previous pneumonia (OR = 10.80; 95% CI = 4.52-25.77); having had more than six upper respiratory tract infections (URTIs) (OR = 2.95; 95% CI = 2.11-4.14); having had first URTI before the third month of life (OR = 1.50; 95% CI = 1.04-2.17); living in a moderately polluted area (OR = 1.59; 95% CI = 1.08-2.33); paracetamol use for URTI (OR = 2.13; 95% CI = 1.54-2.95); and antibiotic use for skin infection (OR = 2.29; 95% CI = 1.18-4.46).Conclusionsthe study of risk factors for wheezing in the first year of life is important to help physicians identify young children at high risk of developing asthma and to improve public health prevention strategies in order to reduce the morbidity of wheezing in childhood.     

Prevalence and risk factors of asthma and allergic diseases among schoolchildren in Bolu, Turkey

AIM: In this study we aimed to detect the prevalence and risk factors of asthma and allergic diseases in children aged between 7 and 14 years old at rural and urban areas of Bolu, Turkey. METHODS: Questionnaire of International Study of Asthma and Allergies in Childhood (ISAAC) phase one and questionnaire including questions about family, demographic, socio-economic characteristics of children were applied to 931 schoolchildren who were selected by randomized sampling. RESULTS: In children, the prevalence of diseases and symptoms were as follows: wheeze ever: 15.5%, asthma: 5.6%, nasal symptoms ever: 41.4%, allergic rhinitis: 23.2%, itchy rash ever: 5.9% and eczema: 5.0%. In multivariate regression analysis, presence of allergic disease in the family was risk factor for wheezing (OR=1.74, 95% CI=1.19-2.76), asthma (OR=2.19, CI=1.06-4.52), allergic rhinitis (OR=2.68, CI=1.80-3.98) and eczema (OR=2.33, CI=1.17-4.65); living in shanties was risk factor for allergic rhinitis (OR=5.26, CI=2.1-13.16); a monthly income below $300 was risk factor for asthma (OR=2.54, CI=1.06-6.08). CONCLUSION: It was detected that the prevalence of allergic rhinitis and its symptoms was more common in schoolchildren living in Bolu. Presence of allergic disease in fathers or mothers and low socio-economic level increase the risk of asthma and other allergic diseases in children.     

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.     

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.     

Prevalence of and factors associated with current asthma symptoms in school children aged 6-7 and 13-14 yr old in Bogotá, Colombia.

This cross-sectional study of children aged 6-7 years and adolescents aged 13-14 years in Bogotá, Colombia, assessed the prevalence of asthma symptoms and their associations with dietary, health, and behavioral habits. This study is part of the International Study of Asthma and Allergies in Childhood (ISAAC)-phase III. Asthma prevalence among the children was assessed using a parental self-administered written questionnaire (WQ), and among adolescents using a WQ together with a video questionnaire (VQ). Associations were estimated with bivariate and multivariate analysis. The study found that the 6-7 year age-group were more likely to report current asthma symptoms than the 13-14 year age-group (10.4% [WQ] vs. 8.6% [WQ] and 8.0% [VQ], respectively). Factors associated with current asthma symptoms among the 6-7 year age-group included higher maternal education (OR = 1.7, [95% CI 1.2-2.6], p = 0.007), a cat in the home during the last year (OR = 1.5, [95% CI 1.0-2.3], p = 0.036), watching TV 1-2 hours/day (OR = 2.1, [95% CI 1.2-3.9], p = 0.013), and medication with acetaminophen in the first and most recent year of life (OR = 1.8, [95% CI 1.3-2.4], p < 0.001; OR = 2.2, [95% CI 1.7-2.8], p < 0.001, respectively) or antibiotics in the first year of life (OR = 1.9, [95% CI 1.4-2.5], p < 0.001). Among the 13-14 year age-group, factors associated with current asthma symptoms included medication with acetaminophen during the last year (OR = 1.8, [95% CI 1.4-2.3], p < 0.001); cereal, milk, and fruit consumption 3 or more times weekly (OR = 1.5, [95% CI 1.1-1.9], p = 0.010; OR = 0.8, [95% CI 0.6-1.0], p = 0.046; OR = 0.6, [95% CI 0.4-1.0], p = 0.031, respectively). Overall, compared with that in other Latin American centers, asthma prevalence in Bogotá is close the lower estimates. However, associations with dietary, health, and behavioral habits need further study to assess their complex relationship with asthma.     

Day care attendance, respiratory tract illnesses, wheezing, asthma, and total serum IgE level in early childhood

BACKGROUND: It has been hypothesized that day care--related infections may explain the inverse relation between day care attendance in early life and asthma in childhood. OBJECTIVE: To examine the relation between day care attendance or respiratory tract illnesses in the first year of life and wheezing and asthma in the first 4 years of life among children with a parental history of atopy who were followed up from birth. RESULTS: Day care attendance in the first year of life was inversely associated with geometric mean total serum IgE level (12.9 [+/-1 SD = 3.3, 51.4] IU/mL for day care vs 18.5 [[+/-1 SD = 5.3, 64.7] IU/mL for no day care; P =.03) at 2 years of age but not significantly associated with wheezing at or after 2 years of age. Having at least 1 physician-diagnosed lower respiratory tract illness in the first year of life was significantly associated with recurrent wheezing (odds ratio [OR], 2.0; 95% confidence interval [CI], 1.0-4.1) and asthma (OR, 2.5; 95% CI, 1.1-5.5) at 4 years of age, but not with any wheezing (infrequent and frequent) at 3 years or older. Illnesses of the upper respiratory tract (> or = 1 physician-diagnosed upper respiratory tract illness or > or = 3 episodes of nasal catarrh) in the first year of life were associated with any wheezing (frequent and infrequent) between the ages of 1 and 4 years, but not with recurrent wheezing or asthma at 4 years of age. CONCLUSIONS: Our results suggest that among children with a parental history of atopy the protective effect of day care attendance in early life against the development of atopy has begun by 2 years of age, and that a protective effect of day care attendance in early life against wheezing may not be observed until after 4 years of age.     

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.     

Prevalence and correlates of paediatric asthma and wheezing in a largely rural USA population

OBJECTIVE: The prevalence of asthma among children has been increasing in the United States and it is estimated that there are approximately 5 million children with asthma. This cross-sectional survey sought to estimate the prevalence of asthma and asthma symptoms and potential risk factors among children aged 16 and younger, in a largely rural population in the USA. METHODS: This study was a telephone survey of 1500 households in the South Plains/Panhandle region of Texas. Parents of children were interviewed with a response rate of 64%. Having been diagnosed with asthma by a physician and a report of wheezing in the last 12 months were used as dependent variables in multivariate logistic regressions with several sociodemographic and environmental factors as potential confounders. RESULTS: The age-adjusted prevalence of asthma and wheezing among children were approximately 15 and 18%, respectively. The prevalence of asthma was highest (20%) among children aged 11-16 (P < 0.001). Living in urban areas was associated significantly with asthma and wheezing. Non-Hispanic blacks reported significantly increased odds of asthma in their children (adjusted odds ratio (OR) = 2.04, 95%CI 1.02-4.08), whereas Mexican-Americans reported significantly reduced odds of asthma (adjusted OR = 0.48, 95%CI 0.29-0.78) and wheezing (adjusted OR = 0.58, 95%CI 0.37-0.89) in their children. The odds of asthma (adjusted OR = 1.78, 95%CI 1.09-2.92) and wheezing (adjusted OR = 2.45, 95%CI 1.52-3.95) was highest among children in the highest body mass index quartile. No significant association with pet ownership and exposure to second-hand smoke with asthma and wheezing was observed in this study. CONCLUSION: Urban residence, non-Hispanic black and Mexican-American race/ethnicity, and being overweight were significantly associated with the increased risk of asthma and/or wheezing.     

Prevalence and risk factors associated with wheezing in the first year of life

Objectiveto investigate the prevalence and risk factors associated with wheezing in infants in the first year of life.Methodsthis was a cross-sectional study, in which a validated questionnaire (Estudio Internacional de Sibilancias en Lactantes - International Study of Wheezing in Infants - EISL) was applied to parents of infants aged between 12 and 15 months treated in 26 of 85 primary health care units in the period between 2006 and 2007. The dependent variable, wheezing, was defined using the following standards: occasional (up to two episodes of wheezing) and recurrent (three or more episodes of wheezing). The independent variables were shown using frequency distribution to compare the groups. Measures of association were based on odds ratio (OR) with a confidence interval of 95% (95% CI), using bivariate analysis, followed by multivariate analysis (adjusted OR [aOR]).Resultsa total of 1,029 (37.7%) infants had wheezing episodes in the first 12 months of life; of these, 16.2% had recurrent wheezing. Risk factors for wheezing were family history of asthma (OR = 2.12; 95% CI: 1.76-2.54) and six or more episodes of colds (OR = 2.38; 95% CI: 1.91-2.97) and pneumonia (OR = 3.02; 95% CI: 2.43-3.76). For recurrent wheezing, risk factors were: familial asthma (aOR = 1.73; 95% CI: 1.22–2.46); early onset wheezing (aOR = 1.83; 95% CI: 1.75-3.75); nocturnal symptoms (aOR = 2.56; 95% CI: 1.75-3.75), and more than six colds (aOR = 2.07; 95% CI 1.43- .00).Conclusionthe main risk factors associated with wheezing in Fortaleza were respiratory infections and family history of asthma. Knowing the risk factors for this disease should be a priority for public health, in order to develop control and treatment strategies.     

Prevalence of and factors associated with current asthma symptoms in school children aged 6–7 and 13–14 yr old in Bogotá, Colombia

This cross‐sectional study of children aged 6–7 years and adolescents aged 13–14 years in Bogotá, Colombia, assessed the prevalence of asthma symptoms and their associations with dietary, health, and behavioral habits. This study is part of the International Study of Asthma and Allergies in Childhood (ISAAC)‐phase III. Asthma prevalence among the children was assessed using a parental self‐administered written questionnaire (WQ), and among adolescents using a WQ together with a video questionnaire (VQ). Associations were estimated with bivariate and multivariate analysis. The study found that the 6–7 year age‐group were more likely to report current asthma symptoms than the 13–14 year age‐group (10.4% [WQ] vs. 8.6% [WQ] and 8.0% [VQ], respectively). Factors associated with current asthma symptoms among the 6–7 year age‐group included higher maternal education (OR = 1.7, [95% CI 1.2–2.6], p = 0.007), a cat in the home during the last year (OR = 1.5, [95% CI 1.0–2.3], p = 0.036), watching TV 1–2 hours/day (OR = 2.1, [95% CI 1.2–3.9], p = 0.013), and medication with acetaminophen in the first and most recent year of life (OR = 1.8, [95% CI 1.3–2.4], p < 0.001; OR = 2.2, [95% CI 1.7–2.8], p < 0.001, respectively) or antibiotics in the first year of life (OR = 1.9, [95% CI 1.4–2.5], p < 0.001). Among the 13–14 year age‐group, factors associated with current asthma symptoms included medication with acetaminophen during the last year (OR = 1.8, [95% CI 1.4–2.3], p < 0.001); cereal, milk, and fruit consumption 3 or more times weekly (OR = 1.5, [95% CI 1.1–1.9], p = 0.010; OR = 0.8, [95% CI 0.6–1.0], p = 0.046; OR = 0.6, [95% CI 0.4–1.0], p = 0.031, respectively). Overall, compared with that in other Latin American centers, asthma prevalence in Bogotá is close the lower estimates. However, associations with dietary, health, and behavioral habits need further study to assess their complex relationship with asthma.     

High prevalence of atopy, but not of asthma, among children in an industrialized area in North Italy: The role of familial and environmental factors – a population-based study

The prevalence of atopy and asthma, and their association with familial and environmental factors were investigated among 13- to 14-yr-old children living in Brescia, an industrialized town in North Italy. All the 1450 children attending primary school in the town were invited to participate, and 967 of them (66.7%, 493 males) provided a valid questionnaire filled in by their parents at home. We used a modified version of the questionnaire adopted in the Italian Study of Respiratory Disorders in Childhood and Environment, which is an extended version of the International Study of Asthma and Allergies in Childhood (ISAAC) questionnaire. Six hundred and twenty-eight subjects underwent skin prick test (SPT), and 308 of them (49%) were positive for at least one of the 12 allergen extracts commonly employed. Ninety-nine children (10.2%) had a physician's diagnosis of asthma - 12.4% of the males and 8.0% of the females (p = 0.03). The prevalence of wheezing in the past 12 months was 6.2%. Atopy was found in 76.8% of the subjects with, and in 45.6% of those without physician's diagnosis of asthma (p < 0.001). Analysis by multiple logistic regression showed an inverse association between physician-diagnosed asthma and female sex (odds ratio, OR = 0.5); presence of relatives in the bedroom in initial years of life (OR = 0.6); attending day care (OR = 0.4) and infant school (OR = 0.4); a positive association with parental history of wheezing (OR = 2.5) and asthma (OR = 3.8); and the child's history of asthmatic bronchitis (OR = 31.9) and atopic eczema (OR = 3.8) in the first 2 yr of life. The strength of the associations did not change when restricting the analysis to atopic asthma. In conclusion, atopy and clinical asthma among 13- to 14-yr-old adolescents are significantly associated with some familial and environmental factors, providing further support for the hygiene hypothesis. Prevalence of atopy, but not of asthma, is high in this industrialized area. The strong association found between atopy and clinical asthma suggests that atopy may play a role in causing asthma in genetically predisposed children only.     

Hospitalization for RSV bronchiolitis before 12 months of age and subsequent asthma, atopy and wheeze: A longitudinal birth cohort study

Several epidemiological studies have reported recurrent wheezing and asthma in children after respiratory syncytial virus (RSV) bronchiolitis in infancy. The relationship with allergic sensitization is less clear and recent evidence suggests an interaction between atopy and RSV infection in the development of asthma. Data from a large, population-based, birth-cohort (Avon Longitudinal Study of Parents and Children) were used to compare outcomes of children according to whether or not they had been admitted to hospital in the first 12 months with RSV-proven bronchiolitis. Outcomes considered were 12-month prevalence of wheeze at two ages (between 30-42 and 69-81 months), cumulative prevalence of doctor-diagnosed asthma at 91 months and skin prick test defined atopy at 7 yr. Multivariable logistic regression models were used to calculate odds ratios for outcomes adjusted for potential confounders. A total of 150 infants (1.1% of the cohort) were admitted to hospital within 12 months of birth with RSV bronchiolitis. The prevalence of wheezing was 28.1% in the RSV group and 13.1% in controls at 30-42 months and 22.6% vs. 9.6% at 69-81 months. The cumulative prevalence of asthma was 38.4% in the RSV group and 20.1% in controls at 91 months. Atopy was found in 14.6% of the RSV group and in 20.7% of controls at 7 yr. RSV bronchiolitis was associated with subsequent wheezing between 30-42 (Odds ratio [95% CI] 2.3 [1.3, 3.9]) and 69-81 months (OR 3.5 [1.8, 6.6]) and with the cumulative prevalence of asthma at 91 months (OR 2.5 [1.4, 4.3]) but not with atopy (OR 0.7 [0.2, 1.7]). In a population-based birth cohort, RSV bronchiolitis was associated with subsequent wheezing and asthma but not with the development of atopy by age 7 yr.     

Asthma and overweight are associated with symptoms of gastro-oesophageal reflux

AIM: To explore the prevalence of symptoms suggestive of gastro-oesophageal reflux disease (GERD) in asthmatics and controls, and to control for the possible effect of overweight. METHODS: The prevalence of GERD symptoms was assessed using a questionnaire about reflux symptoms in children with asthma (n=872, mean age 10.4 y, 65% males) compared to non-asthmatic controls (n=264, mean age 10.8 y, 48% males), and a symptom score was calculated. The association between GERD symptoms and overweight (age-adjusted BMI > 25) was assessed independently. RESULTS: A positive reflux symptom score was found in 19.7% of the asthmatics compared to 8.5% of the non-asthmatic control group (odds ratio (OR) 2.6, 95% CI 1.7-4.2). Overweight children reported GERD symptoms more frequently than children with normal weight (OR 1.8, 95% CI 1.2-2.6). Asthma and obesity remained significant predictors when analysed simultaneously by logistic regression analysis. One hundred and fifty-two children with asthma consented to an oesophageal pH study, and an abnormal pH study result (reflux index > 5.0) correlated positively with overweight (OR 4.9, 95% CI 2.2-11.0). CONCLUSION: The prevalence of symptoms associated with gastro-oesophageal reflux was increased in children with asthma and in overweight children. Overweight and asthma were independently associated with GERD symptoms, and overweight did not explain the higher frequency of GERD in asthma patients.     

Development of atopy and wheezing symptoms in relation to heredity and early pet keeping in a Swedish birth cohort

The role of pet keeping during infancy for the development of allergy and asthma is still controversial. The objective of this population-based birth cohort study was to assess the development of atopy and different wheezing phenotypes during the first 4 yr of life in relation to heredity and early pet keeping. The cohort comprised all 1228 infants living in a Swedish county who were born over a 1-yr period. The parents replied to repeated questionnaires and 817 of the children were skin prick tested both at 1 and 4 yr. Cat keeping during the first year of life was associated with an increased risk of a positive skin prick test to cat at 1 yr of age [odds ratio (OR) 2.2, 95% confidence interval (CI) 0.9-5.6], but neither with sensitivity nor clinical symptoms of allergy at 4 yr. Dog keeping during the first year of life was associated with an increased risk of early-onset transient wheezing, but only in children with parental asthma (adjusted OR 4.3, 95% CI 1.5-12.1). In contrast, early dog keeping had an inverse association with sensitivity to pollen allergen at 4 yr (adjusted OR 0.3, 95% CI 0.1-0.9) and late-onset wheezing (adjusted OR 0.4, 95% CI 0.2-1.0). Thus, pet keeping during the first year of life was not associated with an increased risk of atopy at 4 yr, although a positive SPT to cat was more common at 1 yr. Our findings may even suggest that dog keeping during the first year of life might provide some protection from pollen allergy and late-onset wheezing and increase the risk of early-onset transient wheezing in children with heredity for asthma.     

Prevalence of asthma in schoolchildren

OBJECTIVE: To assess the prevalence of asthma symptoms and of asthma in children due to the high frequency of pediatrics patients with symptoms suggestive of the disease and to the lack of data regarding prevalence of asthma in this population. METHODS: We carried out a cross-sectional study with 2,735 school-age children aged 6-7 years and 3,509 adolescents aged 13-14 years selected by random sampling. Data were collected between 1998 and 1999 using a translated version of the questionnaire of the International Study of Asthma and Allergies in Children, which has been previously tested and approved. Guardians were responsible for answering the questionnaire of younger children, whereas adolescents answered their own, in classroom. The data were computed and analyzed using EPI-info software. RESULTS: The response rates for questionnaires were 73.2% (6-7-years old) and 94% (13-14 years old). The prevalence of symptoms in children and adolescents were, respectively: wheezing ever 46.7% and 44.3% (P<0.05); wheezing in the last 12 months 22.7% and 21.2%; speech limited due to wheezing 4.7% and 4.0%; wheezing following exercise 6.3% and 18.2% (P<0.05); nighttime cough in the last 12 months 38.5% and 45.8% (P<0.05); asthma (bronchitis) ever 28.2% and 26.4% (P=0.11). CONCLUSIONS: The prevalence of asthma symptoms and of asthma of the two groups are among the highest results ever reported in Brazil; these results were compatible with those of high prevalence results reported worldwide using ISAAC questionnaires. The high prevalence of symptoms suggests a high prevalence of the disease, which makes asthma an important problem for public health in the region.     

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.     

Impact of low birth weight on early childhood asthma in the United States

OBJECTIVE: To estimate the independent contribution of birth weight to asthma prevalence among children younger than 4 years in the United States and to compare the magnitude of its effect on asthma between African American and white children. DESIGN: Cross-sectional analysis using the 1988 National Maternal-Infant Health Survey and 1991 Longitudinal Follow-up Survey. SETTING: United States. PATIENTS: Eight thousand seventy-one subjects, selected from a randomized, systematic population-based sample and weighted to be nationally representative, who completed both initial and longitudinal follow-up surveys and reported information on asthma diagnosis. MAIN OUTCOME MEASURES: Birth weight and other sociodemographic factors linked to birth outcome were analyzed for independent association with physician-diagnosed asthma by age 3 years. RESULTS: The prevalence of asthma varied by birth weight category: 6.7% in children 2500 g or more at birth, 10.9% in children 1500 to 2499 g at birth, and 21.9% in children less than 1500 g at birth (very low birth weight [VLBW]) (P<.001). Some of the characteristics shown to be independently associated with asthma included: VLBW (odds ratio [OR], 2.9; 95% confidence interval [CI], 2.3-3.6), moderately low birth weight (OR, 1.4; 95% CI, 1.1-1.8), and African American race (OR, 1.9; 95% CI, 1.6-2.4). In stratified analyses, the independent association between VLBW and asthma in white and African American populations was: OR(white), 3.1 (95% CI, 2.2-4.3) and OR(African American), 2.5 (95% CI, 2.0-3.3). The prevalence of VLBW, however, was tripled in African American compared with white children (1.8% vs 0.6%). CONCLUSIONS: These data confirm findings of other studies that identify a strong independent association between low birth weight and asthma. For this 1988 national birth cohort, an estimated 4000 excess asthma cases were attributable to birth weight less than 2500 g. Although the strength of the independent association between VLBW and asthma was smaller in the African American population, the substantially increased prevalence of VLBW in this community may contribute to the disproportionately increased prevalence of asthma among African American children.     

Ureaplasma urealyticum in a neonatal intensive care population

The incidence of Ureaplasma colonization at birth and its effect on the development of chronic lung disease (CLD) and on mortality was studied in a neonatal intensive care population. Ureaplasma colonization was associated with a birthweight < 1000 g (odds ratio [OR] 3.45 confidence intervals [CI] 2.13-5.60) and a gestational age < 30 weeks (OR 2.54 CI 1.71–3.79). In a case-controlled study of 112 infants, significant associations with Ureaplasma colonization were maternal pyrexia in labour ( n = 38 vs 21; P = 0.015), the requirement for antibiotics in labour ( n = 39 vs 16; P = 0.0005) and vaginal delivery ( n = 78 vs 58; P = 0.009). Risk factors associated with the development of CLD were birthweight < 1000 g (OR 3.77 CI 2.53–5.62) and delivery by Caesarean section (OR 1.65 CI 1.11–2.43). Within the group delivered by Caesarean section. Ureaplasma colonization was also associated with an increased risk of CLD (OR 1.97 CI 1.08–3.62). Ureaplasma colonization of infants at birth is associated with factors suggestive of maternal chorioamnionitis as well as preterm birth and low birthweight. In infants delivered by Caesarean section, Ureaplasma colonization is associated with an increased risk of chronic lung disease.