Background The evidence from previous studies on beneficial effects of breast-feeding in relation to development of asthma is conflicting. Objective To investigate the relation between breast-feeding ...and asthma and/or sensitization during the first 8 years of life. Method In a birth cohort, children were followed up to 8 years by questionnaires at ages 2 months and 1, 2, 4, and 8 years to collect information on exposures and health effects. Determination of serum IgE antibodies to common inhalant and food allergens was performed at 4 and 8 years. Longitudinal analyses were applied by using general estimated equations. The study population consisted of 3825 children (93% of the original cohort), of whom 2370 gave blood and 2564 performed lung function measurements at 8 years. Results Children exclusively breast-fed 4 months or more had a reduced risk of asthma during the first 8 years of life (adjusted odds ratio OR, 0.63; 95% CI, 0.50-0.78) compared with children breast-fed less than 4 months. At 8 years, reduced risks of sensitization (adjusted OR, 0.79; 95% CI, 0.64-0.99) and asthma in combination with sensitization (adjusted OR, 0.59; 95% CI, 0.37-0.93) were seen among children exclusively breast-fed 4 months or more. This group also had a significantly better lung function measured with peak expiratory flow. Conclusion Breast-feeding for 4 months or more seems to reduce the risk of asthma up to 8 years. At this age, a reduced risk was observed particularly for asthma combined with sensitization. Furthermore, breast-feeding seems to have a beneficial effect on lung function.
Abstract Background Allergic rhinitis affects 10 to 40% of the population. It reduces quality of life, school and work performance, and is a frequent reason for office visits in general practice. ...Medical costs are large but avoidable costs associated with lost work productivity are even larger than those incurred by asthma. New evidence has accumulated since the last revision of the Allergic Rhinitis and its Impact on Asthma – ARIA guidelines in 2010 prompting its update. Objective To provide a targeted update of the ARIA guidelines. Methods The ARIA guideline panel identified new clinical questions and selected questions requiring an update. We performed systematic reviews of health effects and the evidence about patient values and preferences, and resource requirements (up to June 2016). We followed the Grading of Recommendations Assessment, Development and Evaluation (GRADE) evidence-to-decision frameworks to develop recommendations. Results The 2016 revision of the ARIA guidelines provides updated and new recommendations about the pharmacological treatment of allergic rhinitis. It specifically addresses the relative merits of using oral H1-antihistamines, intranasal H1-antihistamines, intranasal corticosteroids, and leukotriene receptor antagonists either alone or their combination. The ARIA guideline panel provides specific recommendations for the choice of treatment, the rationale for the choice, and discusses specific considerations that clinicians and patients may want to review in order to choose the management most appropriate for an individual patient. Conclusions Appropriate treatment of allergic rhinitis may improve patients’ quality of life, school and work productivity. ARIA recommendations support patients, their caregivers, and health care providers in choosing the optimal treatment.
Background Sensitization to individual cat and dog allergen molecules can contribute differently to development of allergy to these animals. Objective We sought to investigate the association between ...sensitization patterns to cat and dog allergen molecules during childhood and symptoms to these furry animals up to age 16 years. Methods Data from 779 randomly collected children from the Barn/Children Allergy/Asthma Milieu Stockholm Epidemiologic birth cohort at 4, 8, and 16 years were used. IgE levels to cat and dog were determined by using ImmunoCAP, and levels to allergen molecules were determined by using an allergen chip based on ISAC technology (Mechanisms for the Development of Allergy chip). Allergy was defined as reported rhinitis, conjunctivitis, or asthma at exposure to cat or dog. Results Cross-sectionally, IgE to Fel d 1 and cat extract had similar positive predictive values for cat allergy. IgE to Can f 1 showed a higher positive predictive value for dog allergy than dog extract IgE. Sensitizations to Fel d 1 and Can f 1 in childhood were significantly associated with symptoms to cat or dog at age 16 years. Polysensitization to 3 or more allergen molecules from cat or dog was a better longitudinal predictor of cat or dog symptoms than results of IgE tests with cat or dog allergen extract, respectively. Cross-sectionally, cat/dog-polysensitized children had higher IgE levels and more frequent symptoms to cat and dog than monosensitized children. Conclusions Sensitization to Fel d 1 and Can f 1 in childhood and polysensitization to either cat or dog allergen molecules predict cat and dog allergy cross-sectionally and longitudinally significantly better than IgE to cat or dog extract.
Background Peanut allergy affects persons from various geographic regions where populations are exposed to different dietary habits and environmental pollens. Objective We sought to describe the ...clinical and immunologic characteristics of patients with peanut allergy from 3 countries (Spain, the United States, and Sweden) using a molecular component diagnostic approach. Methods Patients with peanut allergy from Madrid (Spain, n = 50), New York (United States, n = 30), Gothenburg, and Stockholm (both Sweden, n = 35) were enrolled. Clinical data were obtained either from a specific questionnaire or gathered from chart reviews. IgE antibodies to peanut extract and the peanut allergens rAra h 1, 2, 3, 8 and 9, as well as to cross-reactive birch (rBet v 1) and grass (rPhl p 1, 5, 7, and 12) pollen allergens, were analyzed. Results American patients frequently had IgE antibodies to rAra h 1 to 3 (56.7% to 90.0%) and often presented with severe symptoms. Spanish patients recognized these 3 recombinant peanut allergens less frequently (16.0% to 42.0%), were more often sensitized to the lipid transfer protein rAra h 9 (60.0%), and typically had peanut allergy after becoming allergic to other plant-derived foods. Swedish patients detected rAra h 1 to 3 more frequently than Spanish patients (37.1% to 74.3%) and had the highest sensitization rate to the Bet v 1 homologue rAra h 8 (65.7%), as well as to rBet v 1 (82.9%). Spanish and Swedish patients became allergic to peanut at 2 years or later, whereas the American children became allergic around 1 year of age. Conclusions Peanut allergy has different clinical and immunologic patterns in different areas of the world. Allergen component diagnostics might help us to better understand this complex entity.
Background Isolated Ara h 8 sensitization is suggested to be associated with no or mild symptoms among peanut-sensitized subjects. Objective We sought to investigate the occurrence of systemic ...reactions in children with isolated sensitization to Ara h 8. Methods Participants were 144 children sensitized to Ara h 8 (≥0.35 kUA /L) but not to Ara h 1, Ara h 2, or Ara h 3 (<0.35 kUA /L). An open oral challenge with peanut was performed in those subjects who did not consume peanut regularly, and an extended IgE reactivity profile was obtained. If the child had a documented history of systemic reactions up to grade I anaphylaxis, double-blind, placebo-controlled food challenges were performed. Results One hundred twenty-nine (89.5%) children were either peanut consumers or did not react to peanut challenge. Another 14 (9.7%) children experienced oral cavity symptoms at the first 2 but not subsequent challenge doses. At the time of the double-blind, placebo-controlled food challenge, 1 boy with a previous mild systemic reaction to peanut experienced lip swelling, stomach cramping, and objective tiredness. Reanalysis of IgE levels showed an increase in peanut IgE levels from 1.5 to 8.8 kUA /L, but IgE levels to Ara h 8 remained stable and IgE levels to Ara h 1, Ara h 2, and Ara h 3 were all still less than 0.35 kUA /L. The IgE level to Ara h 6 was 0.45 kUA /L. Conclusion Isolated Ara h 8 sensitization indicates tolerance to peanuts in almost all cases. However, sensitization against thus far unidentified determinants in peanut might cause symptoms in rare cases.
Background Component-resolved diagnosis might improve the prediction of future allergy in young children. Objective We sought to investigate the association between IgE reactivity to the ...pathogenesis-related class 10 (PR-10) protein family and allergic rhinitis to birch pollen (ARbp ) from early childhood up to age 16 years. Method Questionnaire data and sera obtained at 4, 8, and 16 years of age from the Barn/Children Allergi/Allergy Milieu Stockholm Epidemiologic (BAMSE) study birth cohort were used. Sera from 764 children were analyzed for IgE reactivity to 9 PR-10 allergen proteins at the 3 time points by using an allergen chip based on ISAC technology. ARbp was defined as upper airway symptoms during birch pollen exposure. Results IgE reactivity to Bet v 1 was found in 12%, 17%, and 25% of children at 4, 8, and 16 years of age. IgE reactivity of PR-10 proteins showed a hierarchic intrarelationship: Bet v 1 > Mal d 1 > Cor a 1.04 > Ara h 8 > Pru p 1 > Aln g 1 > Api g 1 > Act d 8 > Gly m 4. There was an increased risk of incidence and persistence of ARbp up to age 16 years with increasing levels of Bet v 1–specific IgE or increasing numbers of IgE-reactive PR-10 proteins at 4 years. Children with severe ARbp at age 16 years had higher levels of Bet v 1–specific IgE at age 4 years compared with children with mild symptoms. Conclusion ARbp at age 16 years can be predicted by analysis of IgE reactivity to PR-10 proteins in early childhood.
Background Eczema (atopic dermatitis) is associated with an increased risk of having IgE antibodies. IgE sensitization can occur through an impaired skin barrier. Filaggrin gene (FLG) mutation is ...associated with eczema and possibly also with IgE sensitization. Objective We sought to explore the longitudinal relation between preschool eczema (PSE), FLG mutation, or both and IgE sensitization in childhood. Methods A total of 3201 children from the BAMSE (Children Allergy Milieu Stockholm Epidemiology) birth cohort recruited from the general population were included. Regular parental questionnaires identified children with eczema. Blood samples were collected at 4, 8, and 16 years of age for analysis of specific IgE. FLG mutation analysis was performed on 1890 of the children. Results PSE was associated with IgE sensitization to both food allergens and aeroallergens up to age 16 years (overall adjusted odds ratio, 2.30; 95% CI, 2.00-2.66). This association was even stronger among children with persistent PSE. FLG mutation was associated with IgE sensitization to peanut at age 4 years (adjusted odds ratio, 1.88; 95% CI, 1.03-3.44) but not to other allergens up to age 16 years. FLG mutation and PSE were not effect modifiers for the association between IgE sensitization and PSE or FLG mutation, respectively. Sensitized children with PSE were characterized by means of polysensitization, but no other specific IgE sensitization patterns were found. Conclusions PSE is associated with IgE sensitization to both food allergens and aeroallergens up to 16 years of age. FLG mutation is associated with IgE sensitization to peanut but not to other allergens. Sensitized children with preceding PSE are more often polysensitized.
Background The role of exposure to air pollution in the development of allergic sensitization remains unclear. Objective We sought to assess the development of sensitization until school age related ...to longitudinal exposure to air pollution from road traffic. Methods More than 2500 children in the birth cohort BAMSE (Children, Allergy, Milieu, Stockholm, Epidemiological Survey) from Stockholm, Sweden, were followed with repeated questionnaires and blood sampling until 8 years of age. Outdoor concentrations of nitrogen oxides, as a marker of exhaust particles, and particles with an aerodynamic diameter of less than 10 μm (PM10 ), mainly representing road dust, were assigned to residential, day care, and school addresses by using dispersion models. Time-weighted average exposures were linked to levels of IgE against common inhalant and food allergens at 4 and 8 years of age. Results Air pollution exposure during the first year of life was associated with an increased risk of pollen sensitization at 4 years of age (odds ratio, 1.83; 95% confidence interval, 1.02-3.28) for a 5th to 95th difference in exposure to nitrogen oxides. At 8 years, there was no general increase in the risk of sensitization; however, the risk of food sensitization was increased, particularly among children free of sensitization at 4 years of age (odds ratio, 2.30; 95% confidence interval, 1.10-4.82). Results were similar by using PM10 . No associations between air pollution exposure after the first year of life and sensitization were seen. Conclusion Traffic-related air pollution exposure does not seem to increase the overall risk of sensitization to common inhalant and food allergens up to school age, but sensitization to certain allergens might be related to exposure during infancy.
Background Not much data are available from large, unselected, birth cohort studies on the natural course and comorbidities of rhinitis in children. Objective To study phenotypes of rhinitis in ...relation to the natural course and comorbidities of allergic diseases in preschool-age and early school-age children. Methods We analyzed data from a birth cohort of 2024 children, for whom information on IgEs against 8 common inhaled allergens was available, collected at age 4 and 8 years. The children were assigned to groups of allergic rhinitis (rhinitis with sensitization to allergens), nonallergic rhinitis (rhinitis without sensitization), allergic sensitization but no rhinitis, or neither rhinitis nor sensitization. Results The proportion of children with allergic rhinitis increased from 5% to 14% from age 4 to 8 years, whereas the proportion of children with nonallergic rhinitis decreased slightly over the same period of development, from 8% to 6%. Of the children with allergic rhinitis when they were 4 years old, 12% underwent remission by the time they were 8 years old; of the children with nonallergic rhinitis, 73% underwent remission during this period of development. Among 4-year-olds without rhinitis who were sensitized to allergen, 56% had allergic rhinitis when they were 8 years old. Among 4- and 8-year-olds, allergic rhinitis and nonallergic rhinitis were associated with asthma, eczema, and food hypersensitivity. Twenty-five percent of 8-year-olds with allergic rhinitis also had oral allergy syndrome. Conclusions Fewer preschool-age children with allergic rhinitis undergo remission than do those with nonallergic rhinitis. Sensitization to inhaled allergens at an early age (4 years) precedes the development of allergic rhinitis, whereas symptoms of rhinitis do not. Oral allergy syndrome is common among 8-year-olds with allergic rhinitis.
Background The nature of allergens and route and dose of exposure may affect the natural development of IgE and IgG responses. Objective We sought to investigate the natural IgE and IgG responses ...toward a large panel of respiratory and food allergens in subjects exposed to different respiratory allergen loads. Methods A cross-sectional analysis was conducted in 340 adults of the EGEA (Epidemiological study of the Genetics and Environment of Asthma, bronchial hyperresponsiveness and atopy) (170 with and 170 without asthma) cohort. IgE and IgG responses to 47 inhalant and food allergen components were analyzed in sera using allergen microarray and compared between 5 French regions according to the route of allergen exposure (inhaled vs food allergens). Results Overall 48.8% of the population had allergen-specific IgE levels of 0.3 ISAC standardized units (ISU) or more to at least 1 of the 47 allergens with no significant differences across the regions. For ubiquitous respiratory allergens (ie, grass, olive/ash pollen, house dust mites), specific IgE did not show marked differences between regions and specific IgG (≥0.5 ISU) was present in most subjects everywhere. For regionally occurring pollen allergens (ragweed, birch, cypress), IgE sensitization was significantly associated with regional pollen exposure. For airborne allergens cross-reacting with food allergens, frequent IgG recognition was observed even in regions with low allergen prevalence (Bet v 1) or for allergens less frequently recognized by IgE (profilins). Conclusions The variability in allergen-specific IgE and IgG frequencies depends on exposure, route of exposure, and overall immunogenicity of the allergen. Allergen contact by the oral route might preferentially induce IgG responses.
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