Atopy in childhood. II. Relationship to airway responsiveness, hay fever and asthma

While airway hyperresponsiveness is usually associated with a diagnosis of asthma or symptoms of wheezing, some individuals with rhinitis show airway hyperresponsiveness as do some with no symptoms whatsoever. We have studied the correlations between symptoms, airway hyperresponsiveness and atopy as determined by skin-prick tests in a cohort of New Zealand children. A total of 662 members of a birth cohort were studied at age 13 years using a respiratory questionnaire, skin-prick tests to 11 common allergens, and an abbreviated validated methacholine challenge test to determine airway responsiveness. Airway hyperresponsiveness (methacholine PC20 FEV1 < or = 8 mg/ml) was strongly correlated with reported asthma and current wheezing (P<0.0001) and also with atopy, especially to house dust mite and cat (P<0.0001). As weal size for both house dust mite and cat increased, so did the proportion of children with airway hyperresponsiveness. All children with diagnosed asthma and airway hyperresponsiveness were atopic. Skin-test reactions to house dust mite and cat were strongly correlated with any degree of measurable airway responsiveness (PC20 FEV1 < or = 25 mg/ml) in children with rhinitis (P<0.00001), and remained significantly correlated even in children without current asthma, without asthma ever and without rhinitis (P<0.001). Atopy is a major determinant of airway hyperresponsiveness in children, not only in those with reported histories of asthma and wheezing, but also in the absence of any history suggesting asthma and rhinitis.     

Atopy in childhood. I. Gender and allergen related risks for development of hay fever and asthma

Reasons for the gender differences in prevalence rates for asthma remain unclear. We have examined the relationships between allergen skin-test reactions and diagnoses of hay fever and asthma in New Zealand boys and girls examined at the age of 13 years. Information on current and past wheezing, diagnosed asthma, and hay fever was obtained for 662 subjects (341 boys) of a birth cohort followed longitudinally to the age of 13 years, using a physician-administered questionnaire. Atopic status was determined by skin-prick tests to 11 common allergens. The proportion of 13-year-old boys with current asthma was 1.6 times higher and of ever-diagnosed asthma 1.4 times higher than in girls, but the prevalence of recurrent wheeze (> or = three episodes per year) not diagnosed as asthma, or of hay fever, was not significantly different between the sexes. The prevalence of diagnosed asthma increased with increasing numbers of positive skin tests, but hay fever without asthma was little affected above one positive skin-test. Boys had a greater prevalence of any positive skin-test (50.1% vs 37.1%), two or more positive tests (29.3% vs 21.8%), and responses to house dust mite (34.0% vs 23.1%) and cat (14.7% vs 11.2%). Gender differences for asthma became insignificant when adjusted for skin-test responsiveness to house dust mite and/or cat. The proportion of children with diagnosed asthma increased with increasing size of weals to house dust mite and cat dander. Gender differences in allergen sensitivities partly explain the gender differences in diagnosed asthma in children. In both sexes, risk of asthma was primarily associated with sensitization to indoor allergens (house dust mite and cat), and was related to the magnitude of the skin-test response, while the risk of hay fever was primarily associated with grass pollen sensitivity.     

Self-reported hay fever and panic attacks in the community.

OBJECTIVE: The objective of this study was to determine the relationship between self-reported hay fever and common mental disorders among adults in the general population. METHODS: Data were drawn from the Midlife Development in the United States Survey, a representative household survey of the adult US population (25 to 74 years old; n = 3,032). Multivariate logistic regression analyses were used to determine the relationship between self-reported hay fever and current major depression, panic attacks, generalized anxiety disorder, and alcohol/substance use disorders. RESULTS: Self-reported hay fever was associated with a significantly increased odds of panic attack (odds ratio = 1.8 [1.2, 2.6]), which persisted after adjusting for differences in sociodemographic characteristics and comorbid mental disorders. Self-reported hay fever was not associated with a significantly increased likelihood of major depression, generalized anxiety disorder, or alcohol/substance use disorders. CONCLUSIONS: Consistent with previous findings, these data show a relationship between self-reported hay fever and increased likelihood of panic attacks among adults in the general population. The mechanism of the observed association remains unknown. Future work that examines the relationship between hay fever and panic attacks, as well as other mental disorders using both self-report and objective measurement of allergic response in prospective, longitudinal, epidemiologic data may be useful in improving our understanding of this observed link.     

Natural history of hay fever and pollen sensitization,and doctors' diagnosis of hay fever and pollen asthma in German schoolchildren

BACKGROUND: In order to prevent pollen asthma by immunotherapy it is mandatory to know the best time to initiate it. Children with hay fever complaints are at considerable risk of developing pollen asthma. Population-based data on their natural history is urgently needed. METHODS: A longitudinal cohort study was conducted over four years in six rural towns in Baden-Württemberg, Germany. A questionnaire with questions taken from the International Study of Asthma and Allergies in childhood (ISAAC) was filled in every spring and autumn. Hay fever complaints, asthma defining symptoms and new doctors' diagnosis of hay fever and asthma were recorded. Additionally a skin prick test with pollen allergens was performed every autumn. RESULTS: In 1996, 19.7% of 1101 elementary school children (age: 8.1-9.9 years (5-95%)) were found to be sensitized to pollen and 8.7% had already been diagnosed as having hay fever. In a pooled analysis of 2478 children-summers, children with positive pollen sensitization had a significantly higher risk of developing hay fever symptoms (2.63; 2.17-3.10 odds ratio (OR); 95% confidence interval (CI)) and of being diagnosed as suffering from hay fever (7.88; 4.70-13.20). Furthermore, although their OR for the development of asthma symptoms during the pollen season was 3.88 (2.48-6.07 CI), it was only 0.69 (0.24-2.01 CI) for doctors' diagnosis of pollen asthma. CONCLUSION: Children of elementary school age with pollen sensitization and a history of hay fever are at considerable risk of getting pollen asthma, but they are not quickly diagnosed as such. Specific immunotherapy might be a means of preventing asthma completely in such a situation. Our data helps to estimate the sample size for intervention studies of this kind.     

Beclomethasone dipropionate aerosol in the treatment of seasonal asthma and hay fever

A clinical trial of beclomethasone dipropionate aerosol in seasonal respiratory allergy is reported. Complete control was never achieved, due to acute antigen challenges at the peaks of pollen or spore counts. In ninety-live asthma cases 66.3%, had good control, 10.5% moderate control and 23.2% were failures. In seventy-two hay fever cases, using nasal applicators for the aerosol, 71% had good and 7% moderate control, while 22% were failures of treatment. Steroid aerosol therapy for seasonal respiratory allergy appears to be a satisfactory treatment, free from side effects, and particularly suitable for patients where there are contra-indications to oral steroid therapy, such as peptic ulcer or diabetes mellitus.     

Reduced risk of hay fever and asthma among children of farmers

BACKGROUND: The prevalence of atopic diseases is on the rise. Traditional lifestyles may be associated with a reduced risk of atopy. OBJECTIVES: To test the hypothesis that children living on a farm have lower prevalences of atopic diseases. To identify differences in living conditions between farmers and other families which are associated with the development of atopic conditions. DESIGN: Cross-sectional survey among children entering school (aged 5-7 years). A written questionnaire including the ISAAC core questions and asking for exposures on a farm and elsewhere was administered to the parents. Setting: School health entry examination in two Bavarian districts with extensive farming activity. Subjects: 10 163 children. MAIN OUTCOME MEASURES: The prevalence of doctor's diagnoses and symptoms of hay fever, asthma and eczema as assessed by parental report. RESULTS: Farmers' children had lower prevalences of hay fever (adjusted odds ratio = 0. 52, 95% CI 0.28-0.99), asthma (0.65, 0.39-1.09), and wheeze (0.55, 0. 36-0.86) than their peers not living in an agricultural environment. The reduction in risk was stronger for children whose families were running the farm on a full-time basis as compared with families with part-time farming activity. Among farmers' children increasing exposure to livestock was related to a decreasing prevalence of atopic diseases (aOR = 0.41, 95% CI 0.23-0.74). CONCLUSIONS: Factors related to environmental influences on a farm such as increased exposure to bacterial compounds in stables where livestock is kept prevent the development of allergic disorders in children.     

The long-term effect of moving on patients with asthma and hay fever

This is a “follow-up” study of allergic alumni seen in the University of Iowa Clinics from 15 to 25 years ago. Correspondence with them served to gather information on the long-term effect of a change in locale. The patients were from the Midwest where Alternaria mold and ragweed are the major allergens to which exposure is very heavy. Sixty-two per cent of the patients remaining in the Midwest considered themselves much better than they were years ago. Eighty-three per cent of those who had moved west regarded themselves as all or much better, and in 71 per cent this change had occurred promptly after moving. Improvement experienced in the first year usually was maintained, the development of clinically significant new allergies being uncommon. Fourteen of the 29 patients who had not done well over the years described themselves as having nasal polyps.     

Serious childhood respiratory infections and asthma in adult life. A population based study. ECRHS Italy. European Community Respiratory Health Survey.

BACKGROUND: A number of epidemiologic studies have tried to establish whether respiratory tract infections in early childhood cause obstructive pulmonary disease in adult life. OBJECTIVE: To determine whether reported serious respiratory infection before the age of 5 years (SRI) is a significant risk factor for subsequent development of bronchial asthma and/or bronchial hyperresponsiveness in adults. METHODS: We investigated a random population sample of 1,104 subjects (aged 20 to 40 years), participating in the European Respiratory Health Survey in Italy. Bronchial response to methacholine and answers to a standardized questionnaire were analyzed. RESULTS: The prevalence of SRI (ie, a positive response to the question "Have you ever had a serious respiratory infection before the age of 5 years?") was significantly higher in the subjects with a positive family history of allergic diseases than in those with a negative one (O.R. 1.89; 95% C.I. 1.24 to 2.87, P < .01). No relationship was found between SRI and current adult asthma; however, asthma in the past was found in 20.5% of the SRI positive subjects and in 9.1% of SRI negative subjects (O.R. 2.47; 95% C.I. 1.47 to 4.15, P < .05). No difference in the response to methacholine and in FEV1, FEV1/FVC values was found between SRI positive and SRI negative subjects. CONCLUSIONS: We suggest that a positive family history of atopy is associated with a significantly higher prevalence of SRI. Furthermore our results indicate that exposure to SRI is a risk factor for asthma in the past (ie, asthma in childhood and adolescence) but not for adult asthma or for the development of bronchial impairment in adult life.     

HLA in eczema and hay fever.

The presumed HLA haplotype A1:B8 was more frequent and the combination of A3 and B7 was less frequent in allergic subjects presenting with eczema, than in those presenting with hayfever. A1:B8 was most frequent (36%) in eczema complicated by asthma and/or hay fever, and least frequent (5%) in hay fever alone, considerably above and below the frequency in the general population (17%).     

Pet-keeping in early childhood and airway,nose and skin symptoms later in life

BACKGROUND: It is discussed whether exposure to pets during childhood is a risk or a protective factor for sensitization and allergic symptoms. The aim of this study was to investigate the association between pet-keeping at time of birth and allergic symptoms in airways, nose and skin among young children in Sweden. METHOD: A questionnaire was sent to the parents of 14 077 children (1-6 years), the focus being on allergic symptoms, home environment and other background factors including pet-keeping and avoidance behaviour. The response rate was 79%. RESULTS: Almost one-tenth of the population had got rid of pets because of allergy in the family, and 27.3% reported "avoidance" behaviour towards pets. In a cross-sectional analysis current pet-keeping was "protective", but this may be due to the fact that people avoid exposing their child to something that they believe is a risk factor for allergies. Pet-keeping at the time of birth was associated with "wheezing", "asthma" and "rhinitis on pet-exposure" later in life for children from families with an "avoidance" behaviour, and was not "protective" for other children. There was also an indication of a dose-response relationship between the number of types of furred pets at time of birth and later symptoms in analyses adjusted for avoidance behaviour or current pet-keeping. CONCLUSION: The distribution of pet-keeping in the population is largely explained by avoidance behaviour, meaning that those who have pets mainly are those who can stand them, indicating a "healthy pet-keeping effect".     

Early-onset hay fever in Israeli children

In order to investigate the influence of climate and vegetation on the age of onset and clinical picture of hay fever (HF), we examined 116 children with typical HF living in a single climatic area; fifty-four were from rural farming settlements and sixty-two from towns and cities. Overall age of onset was low; 72% of rural children developed HF between the ages of 2 years and 4 years compared to only 24% of urban children ( P < 0.005). At the same time, 57% of rural children had positive skin tests to more than three pollen extracts out of nineteen allergens tested, compared to 19% of urban children ( P < 0.005). There were no significant differences between the rural and urban groups with regard to the incidence of asthma as part of their HF, nor were there differences in total IgE levels. The results of this study suggest that Israeli children develop hay fever earlier than generally reported in the literature, and that this is most marked in the rural areas. This can be explained by their specific environment, which consists of a basically dry, desert-like climate where lawns, crops and trees are extensively irrigated, leading to the dissemination into the environment of large amounts of pollen grains, which are not washed away because of the lack of rain.     

Austrian children living on a farm have less hay fever, asthma and allergic sensitization

BACKGROUND AND OBJECTIVES: In some studies, the prevalence of hay fever and asthma has been found to be lower in children from rural areas than in children from an urban environment. We hypothesized that living on a farm might be protective against development of allergic sensitization and allergic diseases. METHODS: In a cross-sectional survey, parents of 2283 children aged 8-10 years from a mostly rural area in Austria answered a standardized questionnaire on allergic diseases and environmental factors. 1137 children performed a skin prick test to seven local allergens. RESULTS: The prevalence of hay fever (3.1 vs 10.3%, P = 0.0002), asthma (1.1 vs 3.9%, P = 0.017) and a positive skin prick reactivity to at least one of the common local allergens (18.8 vs 32.7%, P = 0. 001) was significantly lower in children living on a farm than in children from a non-farming environment. In a multivariate logistic regression model, adjusting for genetic background, parent education, living and housing conditions and dietary factors did not change the odds ratio for the association of farming and allergic sensitization. Only after including 'regular contact with livestock and poultry' into the model did the odds ratio change significantly (cOR 0.48 95% CI 0.30-0.75 to aOR 0.75 95% CI 0.37-1.52) indicating an association between regular contact with farm animals and reduced risk of atopic sensitization. CONCLUSION: Possible explanations for the lower prevalence of hay fever, asthma and allergic sensitization in children living on a farm might be the development of immunotolerance or the stimulation of TH1 cells and suppression of TH2 cells by increased exposure of farm children to microbial antigens in the stables or farmhouses.