Clinical atopy and associated factors in primary-school pupils

To investigate potential risk factors for clinical atopy in childhood, we obtained cross-sectional data from a cohort of 1376 8-year-old pupils. Parental atopy (hay fever, asthma, eczema), gestational age, maternal smoking habits, and the child's history of asthma, hay fever, and eczema were ascertained by questionnaire. Combining the history and the result of a skin prick test using seven aeroallergens, we defined the child's atopic diseases. Of the population evaluated, 25.4% were categorized as atopic (10.2% allergic asthma, 17.3% eczema, 6.9% hay fever). As compared with the clear nonatopics (40.2%), parental atopic diseases were more prevalent in each of the atopic groups. Significant associations of the parents' and child's disease were obvious for eczema and hay fever. Low gestational age (LGA) was more frequent in children with any atopy or with an allergic asthma (odds ratio (OR) 1.7; 95% confidence interval (CI) 1.02-2.97; OR 2.8; 95% CI 1.5-5.4). Hay fever and allergic asthma occurred less frequently in girls (OR 0.5; 95% confidence interval 0.3-0.8; OR 0.6; 95% CI 0.4-0.9). In conclusion, our data underline the importance of parental atopy for the clinical outcome in the offspring. In addition, LGA appears to be a risk factor for allergic asthma and for general atopy in later life.     

Breastfeeding and the prevalence of symptoms of allergic disorders in Japanese adolescents

BACKGROUND: Environmental factors acting early in life are key determinants of the incidence of allergic disease. Whether breastfeeding is protective against allergic disorders remains controversial. OBJECTIVE: The present cross-sectional study examined the relationship between feeding patterns in the first 3 months of life and the prevalence of symptoms of wheeze, atopic eczema, and rhinoconjunctivitis during the past 12 months in Japanese adolescents. METHODS: The subjects were 5614 of 9008 students (62%) aged 12-15 years from all public junior high schools in Suita, Japan in 2001. This study used the diagnostic criteria of the International Study of Asthma and Allergies in Childhood. Adjustment was made for gender, grade, number of older siblings, and parental history of allergy. RESULTS: Feeding pattern was unrelated to the prevalence of wheeze or rhinoconjunctivitis. The prevalence of atopic eczema was significantly higher in children who had been breastfed than in artificial milk feeders (adjusted odds ratios = 1.40 and 1.56, 95% confidence intervals: 1.01-1.98 and 1.13-2.22 for mixed milk intake and breastfeeding only vs. artificial milk consumption, respectively; P = 0.01 for linear trend). When children were divided according to a positive or negative allergic history in at least one parent, an increased prevalence of atopic eczema associated with breastfeeding was found in children with a negative parental allergic history compared with those with a positive parental allergic history. CONCLUSION: The findings suggest that breastfeeding may be associated with an increased prevalence of atopic eczema, especially among children without a parental history of allergy.     

Extrinsic and intrinsic asthma: influence of classification on family history of asthma and allergic disease

The distributions of asthma, hay fever and eczema were examined in the first degree relatives of 516 asthmatics grouped according to atopic status, history of hay fever/eczema and history of asthma provoked by pollens, dust or animals. The prevalences of both asthma and eczema in relatives were strongly correlated with the presence of hay fever/eczema in probands and to a lesser extent with their atopic status. The prevalence of hay fever in relatives was strongly correlated with both the presence of hay fever/eczema and the degree of atopy in probands. In contrast, allergic provocation of asthma in probands did not influence the prevalences of asthma, hay fever or eczema. These findings are consistent with the hypothesis that there is an increased risk of asthma in relatives of atopic asthmatics which may arise from the enhanced susceptibility to asthma of individuals who inherit both a predisposition to asthma and a predisposition to atopy.     

Trends in prevalence of asthma, allergic rhinitis and atopic dermatitis in 5-7-year old Swiss children from 1992 to 2001

BACKGROUND: Changing occurrence rates of asthma, allergic rhinitis and atopic dermatitis are of public health concern and require surveillance. Changes in prevalence rates of these atopic diseases were monitored during 10 years and their trend with time was determined taking into account the influence of personal and environmental risk factors. METHODS: Four cross-sectional surveys in 5-7-year old children were performed in seven different communities in Switzerland between 1992 and 2001. Prevalence of respiratory and allergic symptoms and of affecting risk factors including parental environmental concern were assessed using a standardized parental questionnaire. RESULTS: A total of 988 (74.1%), 1778 (79.0%), 1406 (82.6%) and 1274 (78.9%) children participated, respectively, in the 1992, 1995, 1998 and 2001 surveys. Prevalence rates of asthma and hay fever symptoms remained quite stable over time (wheeze/past year: 8.8%, 7.8%, 6.4% and 7.4%, sneezing attack during pollen season: 5.0%, 5.6%, 5.4% and 4.6%). Rates of reported atopic dermatitis symptoms (specific skin rash/past year: 4.6%, 6.5%,7.4% and 7.6%) showed an increase over time, but those of diagnosis of eczema did not show a clear pattern (18.4%, 15.7%, 14.0% and 15.2%). Stratified analysis by parental environmental concern and by parental atopy showed similar trends. Rates of atopic dermatitis symptoms showed significant increase in girls but stayed stable in boys. CONCLUSION: Results of these four consecutive surveys suggest that the increase in prevalence of asthma and hay fever in 5-7-year old children living in Switzerland may have ceased. However, symptoms of atopic dermatitis may still be on the rise, especially among girls.     

Pet-keeping in childhood and adult asthma and hay fever: European community respiratory health survey

BACKGROUND: Whether pet-keeping early in life protects against or promotes allergy remains unclear. OBJECTIVE: Our aim was to examine the effects of childhood pet-keeping on adult allergic disease in a large international population-based study, including information on sensitization, adult pet-keeping, and pet prevalence in the populations. METHODS: We used information from structured interviews (n = 18,530) and specific IgE to common aeroallergens in blood samples (n = 13,932) from participants in the European Community Respiratory Health Survey (ECRHS) to analyze the associations between keeping pets and adult asthma and hay fever. RESULTS: Keeping cats in childhood was associated with asthma only among atopic subjects, an association that varied between centers (P =.002) and was stronger where cats where less common (< 40% cats: odds ratio(wheeze) [OR(wheeze)] = 1.84, 95% CI = 1.31-2.57; 40%-60% cats: OR(wheeze) = 1.33, 95% CI = 1.10-1.61; > or =60% cats: OR(wheeze) = 0.98, 95% CI = 0.73-1.33). Dogs owned in childhood or adulthood were associated with asthma among nonatopic subjects (childhood: OR(wheeze) = 1.28, 95% CI = 1.13-1.46; adulthood: OR(wheeze) = 1.31, 95% CI = 1.14-1.51; both: OR(wheeze) = 1.69, 95% CI = 1.40-2.04). In atopic subjects, those who had owned dogs in childhood had less hay fever (OR = 0.85; 95% CI = 0.73-0.98) and no increased risk of asthma (OR(wheeze) = 1.01, 95% CI = 0.87-1.17). Respiratory symptoms were more common in subjects who had owned birds during childhood (OR(wheeze) = 1.12; 95% CI = 1.02-1.23) independent of sensitization. CONCLUSIONS: The effects of pet-keeping in childhood varied according to the type of pet, the allergic sensitization of the individual, and the wider environmental exposure to allergen. Cats owned in childhood were associated with more asthma in sensitized adults who grew up in areas with a low community prevalence of cats. Dogs owned in childhood seemed to protect against adult allergic disease but promote nonallergic asthma.     

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.     

Tuberculin reactivity and allergic disorders in schoolchildren, Okinawa, Japan

Background Bacillus Calmette‐Guérin (BCG) vaccination triggers a T‐helper type 1 response. Whether BCG vaccination and positive tuberculin reactivity are preventive against allergic disorders remains controversial. Objective The current cross‐sectional study investigated the relationship of BCG vaccination and tuberculin reactivity with the prevalence of allergic disorders using data from the Ryukyus Child Health Study (RYUCHS). Methods Subjects were 5717 schoolchildren aged 8–11 years in Okinawa, Japan. The RYUCHS collected information on symptoms of allergic disorders and potential confounding factors. The outcomes were based on diagnostic criteria from the International Study of Asthma and Allergies in Childhood. Data on BCG vaccination and tuberculin tests were obtained from school records. Allowance was made for grade, sex, sibship size, smoking in the household, paternal and maternal history of asthma, atopic eczema, and allergic rhinitis, and paternal and maternal educational level. Results No measurable relationship was found between BCG vaccination in infants and the prevalence of allergic disorders. Among 5567 BCG‐vaccinated children, positive tuberculin reactivity (induration 10 mm) in the first grade was independently associated with a decreased prevalence of wheeze, asthma, and atopic eczema: the multivariate odds ratios for wheeze, asthma, and atopic eczema were 0.80 (95% confidence interval [CI], 0.67–0.94), 0.78 (95% CI, 0.64–0.95), and 0.77 (95% CI, 0.62–0.95), respectively. The inverse associations were more pronounced in children with a negative parental allergic history than in those with a positive parental allergic history. There was no significant relationship between tuberculin reactivity and allergic rhinoconjunctivitis. Conclusions The findings suggest that positive tuberculin reactivity may be inversely associated with the prevalence of wheeze, asthma, and atopic eczema, but not allergic rhinoconjunctivitis, especially among Japanese children without a parental allergic history.     

Epidemiology of food allergy/food intolerance in adults: associations with other manifestations of atopy

BACKGROUND: Food allergy and food intolerance (FA/FI) are believed to be frequent medical problems; however, information from epidemiologic studies in adults is scarce. The objective was to determine the frequency of FA/FI and allergic sensitization to food in a large adult sample. Furthermore, the associations between FA/FI and other outcomes of atopy were studied. METHODS: Within a population-based, nested, case-control study, a standardized interview was performed to obtain detailed information on FA/FI and the history of atopic diseases. In addition, a skin prick test with 10 common food and nine aeroallergens was performed. RESULTS: Overall, 20.8% of the 1537 studied subjects (50.4% female, age median 50 years) reported FA/FI (women 27.5%, men 14.0%; OR 2.35, CI 1.80-3.08). Nuts, fruits, and milk most frequently led to adverse effects, and the sites of manifestation were oral (42.9%), skin (28.7%), gastrointestinal (13.0%), systemic (3.2%), and multiple (12.2%). One-quarter of the subjects (25.1%) were sensitized to at least one food allergen in the prick test, with hazelnut (17.8%), celery (14.6%), and peanut (11.1%) accounting for most of the positive reactions. The corresponding frequency estimates for the representative study base (n=4178) were 15.5% for reported adverse reactions and 16.8% for allergic sensitization. Relevant concomitant sensitization to food and aeroallergens was observed. Food-allergic subjects (positive history and sensitization to corresponding allergen) suffered significantly more often from urticaria, asthma, atopic eczema, and especially hay fever (73.1%) than controls (3.0%). Furthermore, hay fever was treated significantly more often in subjects who suffered from concomitant food allergy. CONCLUSIONS: FA/FI in adults is frequently reported and associated with other manifestations of atopy. Hay fever in conjunction with FA/FI tends to be clinically more severe since therapeutic needs are enhanced.     

Does the use of antibiotics in early childhood increase the risk of asthma and allergic disease?

BACKGROUND: One of the mechanisms evoked to explain the increasing prevalences of asthma and allergy, in particular among children, is the 'Western lifestyle' or 'hygiene' hypothesis. As early childhood infections are assumed to hold a protective effect on the development of asthma and allergies, the use of antibiotics at that sensitive age may lead to an increased risk of asthma and allergy. OBJECTIVE: The aim of this study is to investigate the association between the use of antibiotics in the first year of life and the subsequent development of asthma and allergic disorders. METHODS: In a population-based sample of 7-and-8-year-old children questionnaire and skin prick test data were collected from 1206 and 675 subjects, respectively. Prevalence rates of asthma, allergic disorders and skin test positivity were compared between children with and without early life use of antibiotics, taking into account other possible risk factors including early respiratory infections. The effect of genetic predisposition was investigated by stratified analyses of children with and without parental hay fever. RESULTS: The use of antibiotics during the first year of life was significantly associated with asthma (OR = 1.7, 95% CI 1.0-3.1), hay fever (OR = 2.3, 95% CI 1.3-3.8) and eczema (OR = 1.3, 95% CI 1.0-1.8). No significant relationship was found with skin test positivity (OR = 1.1, 95% CI 0.7-1.7). After stratification for the presence of parental hay fever, children without parental hay fever did not show any significant associations between antibiotics use and asthma or allergy, whereas in children with parental hay fever the use of antibiotics was significantly related with asthma (OR = 2.3, 95% CI 1.1-5.1), hay fever (OR = 2.8, 95% CI 1.5-5.1) and eczema (OR = 1.6, 95% CI 1.0-2.6), and of borderline statistical significance with skin test positivity (OR = 1.6, 95% CI 0.9-3.0). CONCLUSION: Early childhood use of antibiotics is associated with an increased risk of developing asthma and allergic disorders in children who are predisposed to atopic immune responses. These findings support recent immunological understanding of the maturation of the immune system.     

Number of offspring and maternal allergy

The consistent association seen between family size and childhood allergy has led to the 'hygiene hypothesis', namely that a lower frequency of infections in early childhood is associated with an increased risk of asthma and hay fever. Maternal atopy, however, is a strong predictor of childhood asthma and hay fever. If maternal atopy is inversely related to the number of siblings then the role of siblings in the development of childhood atopy, the basic tenet of the 'hygiene hypothesis', is challenged. We evaluated the association between number of pregnancies and number of live births with lifetime occurrence of maternal wheeze, asthma, allergic rhinitis, and allergic conjunctivitis in a cross-sectional study in four areas in Italy. A total of 1755 (35-74 year old) nonsmoking women filled a questionnaire on reproductive history as well as on lifetime occurrence of symptoms/diseases. The number of live births was inversely related to lifetime allergic rhinitis (P-value for trend=0.031) and allergic conjunctivitis (P-value for trend=0.011). The odds ratios for those with 4+ children (in comparison with those having 0-1) were: 0.53 (95% CI: 0.27-1.04) and 0.42 (95% CI: 0.22-0.81), respectively. A similar trend was seen for number of pregnancies, although not statistically significant. No association was found between number of pregnancies and number of live births with wheeze or asthma. The results may be interpreted as an indication that maternal atopy influences pregnancy outcomes or that pregnancy itself has an effect on maternal atopy.     

NAC Manchester Asthma and Allergy Study (NACMAAS): risk factors for asthma and allergic disorders in adults

Asthma and atopic disorders are the most common chronic diseases in the developed countries. Knowledge of the risk factors for these disorders may facilitate the development of preventive strategies aimed at reducing prevalence rates. To investigate the risk factors for asthma and allergic diseases in a large number of adults who are the parents of children in the National Asthma Campaign Manchester Asthma and Allergy Study. All pregnant women and their partners attending "Booking" antenatal clinics were invited to take part in the study. Questionnaire data were collected including the history of asthma and other atopic diseases, pet ownership and smoking habits, and skin prick tests were performed. The prevalence of atopy and the risk factors for asthma and allergic disorders were investigated in all subjects who completed the questionnaire and underwent skin testing. Statistical analysis was carried out using logistic regression. Initially, risk factors were assessed by univariate analysis to see how each potential explanatory variable affected the probability of having allergic disease. Variables were then tested in a forward stepwise multivariate analysis. In 5687 adult subjects there was a very high (48.2%) prevalence of atopy, and 9.7% of subjects had a diagnosis of asthma. In a multivariate regression analysis sensitization to dust mite, cat, dog and mixed grasses were all independently associated with asthma. The odds ratios for current asthma increased with the increasing number of positive skin tests (any two allergens - OR 4.3, 95% CI 3.3-5.5; any three allergens - OR 7.0 95% CI 5.3-9.3; all four allergens - OR 10.4, 95% CI 7.7-14; P < 0.00001). Dog ownership (OR 1.31, 95% CI 1.10-1.57; P = 0.003) and current smoking (OR 1.36, 95% CI 1.15-1.62; P = 0.0004) were significantly and directly associated with "asthma ever". Thirteen per cent of participants reported a history of eczema. In the multivariate analysis the strongest independent associate of eczema was sensitization to dog (OR 1.37, 95% CI 1.14-1.63, P < 0.0001). Apart from dog, the strength of the association between sensitization to common allergens and eczema appeared to be much lower than in the case of asthma. The prevalence of hay fever was high (20.6%), and in the multivariate analysis the association between sensitization to pollen and hay fever was extremely strong (OR 13.6, 95% CI 11.3-16.3; P < 0.0001). The results of the current study emphasize the importance of sensitization to indoor allergens in asthma. However, evidence of a possible direct role of allergen exposure in asthma causation remains unclear.     

The prevalence of asthmatic respiratory symptoms among adults in Estonian and Swedish university cities

The prevalence of atopy and related diseases is lower among children in Eastern European countries than in countries with a market economy. Such comparisons have not been made in adults. The European Community Respiratory Health Survey (ECRHS) postal questionnaire was mailed to random samples of 3000 inhabitants in Tartu, Estonia, and 3600 in Uppsala, Sweden, between the ages of 20 and 44 years. Asthmatic symptoms (wheeze with breathlessness occurring in the absence of colds) were less prevalent in Tartu (4.6% vs 6.8%, P<0.001), as were attacks of asthma (1.9% vs 3.3%, P<0.01), current asthma medication (0.7% vs 4.9%), and allergic rhinitis (17.8% vs 22.2%, P<0.001). Age was inversely related to allergic rhinitis in Uppsala (P<0.05), but not in Tartu. Nocturnal respiratory symptoms (wakening with chest tightness or being woken by an attack of breathlessness or an attack of cough) were more prevalent in Tartu (P<0.001), and their prevalence increased with age (P<0.05) in Tartu, but not in Uppsala. Symptoms of asthma and hay fever were less common but other respiratory problems more common in Tartu than in Uppsala. The difference in the prevalence of hay fever diminished with age, supporting the notion that the increasing prevalence of allergy among children and young adults in Western Europe is caused by a cohort effect.     

Atopic characteristics of children with recurrent wheezing at high risk for the development of childhood asthma

BACKGROUND: Few studies have characterized the atopic profile of toddler-aged children with recurrent wheezing at high risk of the development of persistent asthma. Objective We sought to determine the atopic profile of toddler-aged children with frequent wheeze at high risk for the development of persistent asthma who either had a parental history of asthma, a personal history of atopic dermatitis, or both. METHODS: Participants enrolled in the Prevention of Early Asthma in Kids study (n = 285) on the basis of a modified Asthma Predictive Index were characterized on the basis of allergy and asthma questionnaire responses and allergy skin puncture test results. RESULTS: The majority of the children (60.7%, n = 148) were sensitized to either food or aeroallergens. Male children were significantly more likely to be sensitized to aeroallergens ( P = .03) and to have a blood eosinophil level of 4% or greater ( P = .03) and a total serum IgE level of greater than 100 IU/mL ( P = .0004). Additionally, eosinophilia and total serum IgE level had the strongest correlation with aeroallergen sensitization. CONCLUSION: The high prevalence of aeroallergen sensitization in this high-risk cohort suggests that aeroallergens might have an important role in the early development of asthma. As such, the Prevention of Early Asthma in Kids cohort appears to be an appropriate cohort in which to test whether early intervention with an inhaled corticosteroid can significantly attenuate, or perhaps even prevent, the allergic march from the initial stages of allergic sensitization to the subsequent development of asthma in toddlers with episodic wheezing.     

Manifestation of atopy is not related to patient's month of birth

The first months of life may be an important period for allergic sensitization. Several studies suggest a relationship between the month of birth (MB) and the development of skin sensitivity to aeroallergens or the manifestation of an atopic disease. In 1988 and 1989 we investigated a population of 1066 Bavarian preschool children aged 5–6 years. Skin prick tests were performed with common aeroallergens (grass pollen, birch pollen, house-dust mite, eat epithelia). The personal history of atopic disease (atopic eczema, allergic rhinitis, bronchial asthma) was recorded by a questionnaire, and the presence of overt atopic disease was documented by a personal examination. Positive prick test reactions to the above-mentioned aeroallergens were found in 15.4%, 9.2%, 12.2%, and 10.4% of the subjects, respectively; lifetime prevalence of manifest atopic disease was 22.2% for atopic eczema, 11.7% for allergic rhinitis, and 4.5% for asthma. The MB distributions of children reacting to aeroallergens or of those with atopic diseases were compared with those of subjects with corresponding negative findings. Chi-square tests were performed for each aeroallergen and each of the atopic diseases separately. No significant differences among the MB distributions were found ( P >0.3). Thus, in this coherent group. MB correlated neither to allergic sensitization nor to manifest atopic disease.     

Defining childhood atopic phenotypes to investigate the association of atopic sensitization with allergic disease

AIMS: Although atopic sensitization is common in childhood, its relationship to clinical allergic disease remains incompletely understood. We therefore sought to explore this relationship by defining sensitization based atopic phenotypes. METHODS: Children were recruited at birth (n = 1456) and reviewed at 1, 2, 4 and 10 years. Skin prick testing (SPT) to common allergens was done at 4 (n = 980) and 10 years (n = 1036) with lung function (n = 981), bronchial challenge (n = 784) and serum IgE (n = 953) testing at 10. Atopic phenotypes were defined, by sensitization pattern, for children with SPT at both 4 and 10 years (n = 823). RESULTS: Of phenotyped children, 68.0% were never atopic, 4.3% early childhood atopic (only atopic at age 4), 16.5% chronic childhood atopics (at 4 and 10 years) and 11.2% delayed childhood atopics (only at 10). Never atopics showed small but identifiable prevalence of allergic diseases such as asthma, eczema and rhinitis. Amongst allergen-sensitized subjects, aeroallergen predominated over food sensitization throughout childhood. Chronic childhood atopics showed highest prevalence of lifetime plus persistent wheeze, eczema and rhinitis, increased prevalence of aeroallergen sensitization, some evidence of persistent food sensitization, significantly greater cord IgE than never atopics (P = 0.006), plus higher total IgE (P < 0.001) and bronchial hyper-responsiveness (P < 0.001) at 10 years than other phenotypes. CONCLUSION: A proportion of childhood eczema, rhinitis and asthma is nonatopic. The commonest childhood pattern of atopy is chronic sensitization, associated with early, persisting and clinically significant allergic disease. The currently accepted childhood 'Allergic March' may oversimplify the natural history of childhood atopy and allergic disease.     

Relationship between childhood atopy and wheeze: what mediates wheezing in atopic phenotypes?

BACKGROUND: The nature of the relationship between childhood wheeze and atopy remains uncertain. OBJECTIVE: To characterize childhood wheeze among atopic phenotypes in a longitudinal birth cohort study. METHODS: A whole population birth cohort (N = 1,456) was recruited in 1989. Children were seen at birth and at 1, 2, 4, and 10 years of age to obtain information on asthma and allergic disease development and relevant risk factors for these states. Skin prick testing at ages 4 (n = 980) and 10 (n = 1,036) years was used to define atopic phenotypes. Wheezing in these states was characterized, and logistic regression was used to identify independent risk factors for wheeze onset in different atopic phenotypes. RESULTS: Wheeze ever occurred in 37% of never atopics, 38% of early childhood atopics, 65% of chronic childhood atopics, and 52% of delayed childhood atopics. Chronic childhood atopics had significant wheezing morbidity and bronchial hyperresponsiveness. Their wheezing was associated with male sex, early eczema, family history of eczema, and early tobacco exposure. Never atopic wheeze was related to maternal asthma, parental smoking, and respiratory tract infections. Exclusive breastfeeding protected against early childhood atopic wheeze. Maternal asthma, family history of urticaria, and dog ownership increased delayed childhood atopic wheeze. CONCLUSIONS: In many respects, chronic childhood atopy is the atopic phenotype associated with the most significant forms of childhood wheezing. In such children, heritable drive, allergens, and synergy with other environmental triggers seem to be crucial determinants of wheeze onset. Where such sensitization is absent, numerous environmental factors plus genetic predisposition may assume importance for wheezing.     

Allergic diseases, skin prick test responses, and IgE levels in North Karelia, Finland, and the Republic of Karelia, Russia

BACKGROUND: There is growing evidence to show that atopic diseases are more common in Western Europe than in the former socialist countries of Eastern Europe. OBJECTIVE: The aim of this study was to assess whether a similar difference exists between the most eastern province of Finland and a neighboring western district of Russia. METHODS: A random sample of 25- to 54-year-old subjects was taken from the population registers in the North Karelia Province in eastern Finland and from the Pitk?ranta district across the border in the western part of Russia. Participants filled out a questionnaire on atopic and allergic symptoms and participated in a clinical study, which included skin prick tests with 11 airborne allergens and IgE measurements. RESULTS: Self-reported hay fever, allergic eye symptoms, atopic eczema, and asthma were much more common in Finland than in Russia. In Finland 34.2% and in Russia 21.8% had at least one positive skin prick test reaction. In Finland 21.5% but in Russia only 15.8% had at least one elevated allergen-specific IgE value of the 5 values measured. From 6% to 47% of the differences in self-reported symptoms between the countries were explained by atopy, as measured by means of skin prick testing or specific IgE values. CONCLUSIONS: A major difference in clinical allergic diseases and signs of symptoms was observed between the 2 geographically adjacent areas. This suggests that the difference in clinical allergy and atopic disposition is related to the differences in lifestyle and environmental factors.     

Atopic disease and its determinants – a focus on the potential role of childhood infection

BACKGROUND: Atopic diseases develop on a genetic background and are modulated by environmental factors among which some infectious diseases are thought to have a protective influence. OBJECTIVE: The aim of this study was to determine the influence of infectious diseases in younger ages, bacterial and viral, on atopic diseases and sensitization to aero- and food-allergens in adults. METHODS: A population-based sample of 4262 subjects aged 25-74 years were interviewed concerning their history of infectious disease within the first 18 years of life. Information about allergic disease, including atopic eczema, allergic rhinitis (AR), and asthma was obtained. A blood sample was drawn and analysed for allergen-specific IgE antibodies against food- and aero-allergens. RESULTS: Multiple logistic regression analyses identified viral infection to be associated with AR (adjusted odds ratio (OR) = 1.39; 95% confidence interval (95% CI): 1.13-1.72) and sensitization to aeroallergens (OR = 1.21; 95% CI: 1.05-1.41). Bacterial disease was a negative predictor for atopy development in the subgroup of patients sensitized to nutritional allergens with concomitant atopic eczema (OR = 0.34; 95% CI: 0.11-0.99), AR (OR = 0.67; 95% CI: 0.42-1.07), or asthma (OR = 0.41; 95% CI: 0.19-0.87). Influences of viral and bacterial infection on AR differed with regard to family history of atopic disease. CONCLUSION: In our study population, history of viral infection was consistently positively associated with AR. Our data suggests that bacterial infections might be preventive for specific subgroups of atopy.     

The burden of atopy and asthma in children

Background:  There has been a world-wide increase in the prevalence of atopic diseases. These atopic diseases, including asthma, allergic rhinoconjunctivitis and atopic eczema/dermatitis, are common in childhood and create a challenge of management for physicians and parents.
Methods:  MEDLINE was searched for articles related to atopy, allergy asthma, allergic rhinoconjunctivitis and atopic eczema/dermatitis.
Results and conclusions:  The conditions of asthma, allergic rhinoconjunctivitis and atopic eczema/dermatitis cause very significant burdens regarding the discomfort to the affected individual, management problems for the parent and physician and the economic cost to the family and the nation.