National Institute of Environmental Medicine, Karolinska Institutet, Stockholm, Sweden; Department of Pediatrics, Sachs' Children's Hospital, Stockholm, Sweden. Electronic address: firstname.lastname@example.org.
Both allergic and non-allergic rhinitis are associated with worse asthma control. However, it is unclear how IgE sensitization and/or rhinitis are associated with lung function. We therefore evaluated the effect of rhinitis and sensitization on lung function, including the periphery of the airway system, and inflammatory biomarkers in individuals with and without asthma.
Participants in the BAMSE longitudinal birth cohort study underwent measures of spirometry, impulse oscillometry, and FeNO at age 16 years. Questionnaires were used to obtain data on asthma and rhinitis. Blood samples were analyzed for eosinophils and allergen-specific IgE.
Groups based on the combination of asthma, rhinitis, and sensitization were compared to a healthy reference group. Lower FEV1 /FVC levels were seen for groups with asthma only (adjusted mean difference -2.8% units (95% CI -4.7; -1.0), P
Not much data are available from large, unselected, birth cohort studies on the natural course and comorbidities of rhinitis in children.
To study phenotypes of rhinitis in relation to the natural course and comorbidities of allergic diseases in preschool-age and early school-age children.
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.
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.
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.
There is limited understanding about risk factors for asthma, and few studies have presented an overall picture of factors associated with asthma subtypes in schoolchildren. The aim of this study was to evaluate risk factors and markers of asthma control associated with asthma subtypes up to preadolescence.
A Swedish birth cohort of 3015 children was followed for 12 yr using repeated parental questionnaires. At 8 yr, clinical investigation was performed, specifically evaluating lung function, allergic sensitization (IgE > 0.35 kUA /l), and body mass index (BMI). Children were categorized into three subtypes: transient asthma - asthma at 4 and 8, but not at 12 yr (n = 71), late-onset asthma - asthma at 12 yr, but not earlier (n = 103), and persistent asthma - asthma at 4, 8 and 12 yr (n = 125).
At 8 yr of age, high BMI (>85th percentile), sensitization, and rhinitis were significantly associated with late-onset asthma (p
The role of exposure to air pollution in the development of allergic sensitization remains unclear.
We sought to assess the development of sensitization until school age related to longitudinal exposure to air pollution from road traffic.
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 (PM(10)), 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.
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 PM(10). No associations between air pollution exposure after the first year of life and sensitization were seen.
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.