In the summer forest there are allergens and irritating substances that cause respiratory or cutaneous symptoms. Birch and alder pollen allergy is common in Finland. Pollens of other trees cause sensitization only sporadically. Spores of molds and mushrooms cause allergic reactions, but the means to study spore allergy are inadequate. Even edible mushrooms may cause allergic abdominal discomforts, and trehalose intolerance is supposed to be present in a small percentage of the population. Lichen allergens may bring about IgE-mediated reactions, contact allergy and photoallergic reactions.
The absence of IgE sensitization to allergen components in the presence of sensitization to the corresponding extract has been reported, but its clinical importance has not been studied.
To evaluate the clinical significance of IgE sensitization to three aeroallergen extracts and the corresponding components in relation to the development of respiratory disease.
A total of 467 adults participated in the European Community Respiratory Health Survey (ECRHS) II and 302 in ECRHS III, 12 years later. IgE sensitization to allergen extract and components, exhaled nitric oxide (FeNO) and bronchial responsiveness to methacholine were measured in ECRHS II. Rhinitis and asthma symptoms were questionnaire-assessed in both ECRHS II and III.
A good overall correlation was found between IgE sensitization to extract and components for cat (r = 0.83), timothy (r = 0.96) and birch (r = 0.95). However, a substantial proportion of subjects tested IgE positive for cat and timothy allergen extracts but negative for the corresponding components (48% and 21%, respectively). Subjects sensitized to both cat extract and components had higher FeNO (P = 0.008) and more bronchial responsiveness (P = 0.002) than subjects sensitized only to the extract. Further, subjects sensitized to cat components were more likely to develop asthma (P = 0.005) and rhinitis (P = 0.007) than subjects sensitized only to cat extract.
Measurement of IgE sensitization to cat allergen components would seem to have a higher clinical value than extract-based measurement, as it related better to airway inflammation and responsiveness and had a higher prognostic value for the development of asthma and rhinitis over a 12-year period.
Allergists around the world have different practice styles when administering subcutaneous aeroallergen immunotherapy (IT) in peak pollen seasons, especially when changing doses or frequency of IT. The Immunotherapy practice parameters do not specifically address this issue.
Given the paucity of good data about adjustment of allergen immunotherapy during the pollen seasons, we examined whether a significant difference is present in the way allergists administer immunotherapy during allergy seasons.
To quantify the practice styles of allergists who are members of the American Academy of Allergy, Asthma and Immunology (AAAAI), a self-reported electronic survey was disseminated in September 2010 with the help of the AAAAI Needs Assessment Committee. The responses were tallied and analyzed according to demographic information.
A total of 1,201 allergists in the AAAAI responded to the survey. Most responders practice in an urban or suburban nonacademic practice in the United States and have been in practice for more than 10 years. The size of their practice was variable. Those in practice for more than 10 years were more likely to adjust the dose and frequency of immunotherapy in pollen seasons.
This survey highlights the differences in the practice styles of AAAAI member allergists, and these differences may be associated with their demographic characteristics. Given the wide variability in how allergists adjust dose and frequency of immunotherapy during pollen seasons, establishing guidelines regarding this routine dilemma might help standardize the delivery of treatment to patients.
Epidemiologic data describing the association between allergic sensitization and asthma and allergic rhinitis in adults are scarce.
To determine the prevalence and impact of specific sensitization to airborne allergens on asthma and allergic rhinitis among adults in relation to age.
A random population sample (age 21-86 years) was examined with structured interview and analysis of specific IgE to 9 common airborne allergens. Of those invited, 692 (68%) subjects participated in blood sampling. IgE level of 0.35 U/mL or more to the specific allergen was defined as a positive test result.
Allergic sensitization decreased with increasing age, both in the population sample and among subjects with asthma and allergic rhinitis. In a multivariate model, sensitization to animal was significantly positively associated with asthma (odds ratio [OR], 4.80; 95% CI, 2.68-8.60), whereas sensitization to both animal (OR, 3.90; 95% CI, 2.31-6.58) and pollen (OR, 4.25; 95% CI, 2.55-7.06) was significantly associated with allergic rhinitis. The association between allergic sensitization and rhinitis was consistently strongest among the youngest age group, whereas this pattern was not found for asthma. The prevalence of allergic sensitization among patients with asthma decreased by increasing age of asthma onset, 86% with asthma onset at age 6 y or less, 56% at age 7 to 19 years, and 26% with asthma onset at age 20 years or more.
Sensitization to animal was associated with asthma across all age groups; allergic rhinitis was associated with sensitization to both pollen and animal and consistently stronger among younger than among older adults. Early onset of asthma was associated with allergic sensitization among adults with asthma.
Knowledge about the prevalence of allergies to foods in childhood and adolescence is incomplete. The purpose of this study was to investigate the prevalence of allergies to milk, egg, cod, and wheat using reported data, clinical examinations, and double-blind placebo-controlled food challenges, and to describe the phenotypes of reported food hypersensitivity in a cohort of Swedish schoolchildren.
In a population-based cohort of 12-year-old children, the parents of 2612 (96% of invited) completed a questionnaire. Specific IgE antibodies to foods were analyzed in a random sample (n=695). Children reporting complete avoidance of milk, egg, cod, or wheat due to perceived hypersensitivity and without physician-diagnosed celiac disease were invited to undergo clinical examination that included specific IgE testing, a celiac screening test, and categorization into phenotypes of food hypersensitivity according to preset criteria. Children with possible food allergy were further evaluated with double-blind challenges.
In this cohort, the prevalence of reported food allergy to milk, egg, cod, or wheat was 4.8%. Food allergy was diagnosed in 1.4% of the children after clinical evaluation and in 0.6% following double-blind placebo-controlled food challenge. After clinical examination, children who completely avoided one or more essential foods due to perceived food hypersensitivity were categorized with the following phenotypes: allergy (29%), outgrown allergy (19%), lactose intolerance (40%), and unclear (12%).
There was a high discrepancy in the prevalence of allergy to milk, egg, cod and wheat as assessed by reported data, clinical evaluation, and double-blind food challenges. Food hypersensitivity phenotyping according to preset criteria was helpful for identifying children with food allergy.
We have previously shown that sensitizations to several types of allergens distinguish subjects with and without adult-onset asthma in Finland. The aim was to analyze how age affects sensitization and asthma risk. We used previous population-based case-control data (N=456) from Finnish adult asthma patients with one or two matched controls. Asthma was diagnosed based on a typical history of asthmatic symptoms and lung function tests. Allergic sensitization was determined by skin prick test (SPT) to 17 aeroallergens. Information on demographics was obtained by a questionnaire. Sensitization to more than one allergen type and the number of positive SPT reactions associated with younger age and asthma. Atopic subjects aged 65 and above were characterized by sensitization to only one to two allergens, with very few animal danders and without an association with asthma. Multiple sensitizations and animal dander sensitization are more common among Finnish asthmatic adults aged under 56 than among older asthmatics. Cohort studies are needed to understand timing of host-environmental interactions behind this.
Studies of children's blood lipid profiles in relation to asthma are few, and the results are ambiguous.
We sought to examine whether the lipid profile is associated with concurrent asthma, altered lung function, and allergic sensitization in children.
High-density lipoprotein cholesterol, low-density lipoprotein cholesterol, and triglyceride levels were measured at ages 5 to 7 years in the Copenhagen Prospective Studies on Asthma in Childhood2000 at-risk birth cohort. Asthma and allergic rhinitis were diagnosed based on predefined algorithms at age 7 years along with assessments of lung function, bronchial responsiveness, fraction of exhaled nitric oxide (Feno), and allergic sensitization. Associations between lipid levels and clinical outcomes were adjusted for sex, passive smoking, and body mass index.
High levels of low-density lipoprotein cholesterol were associated with concurrent asthma (adjusted odds ratio [aOR], 1.93; 95% CI, 1.06-3.55; P = .03) and airway obstruction: 50% of forced expiratory flow (aß coefficient, -0.13 L/s; 95% CI, -0.24 to -0.03 L/s; P = .01) and specific airway resistance (aß coefficient, 0.06 kPa/s; 95% CI, 0.00-0.11 kPa/s; P = .05). High levels of high-density lipoprotein cholesterol were associated with improved specific airway resistance (aß coefficient, -0.11 kPa/s; 95% CI, -0.21 to -0.02; P = .02), decreased bronchial responsiveness (aß coefficient, 0.53 log-µmol; 95% CI, 0.00-1.60 log-µmol; P = .05), decreased risk of aeroallergen sensitization (aOR, 0.27; 95% CI, 0.01-0.70; P = .01), and a trend of reduced Feno levels (aß coefficient, -0.22 log-ppb; 95% CI, -0.50 to 0.01 log-ppb; P = .06). High triglyceride levels were associated with aeroallergen sensitization (aOR, 2.01; 95% CI, 1.14-3.56; P = .02) and a trend of increased Feno levels (aß coefficient, 0.14 log-ppb; 95% CI, -0.02 to 0.30 log-ppb; P = .08).
The blood lipid profile is associated with asthma, airway obstruction, bronchial responsiveness, and aeroallergen sensitization in 7-year-old children. These findings suggest that asthma and allergy are systemic disorders with commonalities with other chronic inflammatory disorders.
National Institute of Environmental Medicine, Karolinska Institutet, Stockholm, Sweden; Department of Pediatrics, Sachs' Children's Hospital, Stockholm, Sweden. Electronic address: firstname.lastname@example.org.
Krefting Research Centre / Department of Internal Medicine and Clinical Nutrition, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden. email@example.com
The harmful effects of tobacco smoke on human health, including respiratory health, are extensive and well documented. Previous data on the effect of smoking on rhinitis and allergic sensitization are inconsistent. We sought to investigate how smoking correlates with prevalence of allergic and chronic rhinitis among adults in Sweden.
The study population comprised 27 879 subjects derived from three large randomly selected cross-sectional population surveys conducted in Sweden between 2006 and 2008. The same postal questionnaire on respiratory health was used in the three surveys, containing questions about obstructive respiratory diseases, rhinitis, respiratory symptoms and possible determinants of disease, including smoking habits. A random sample from one of the cohorts underwent a clinical examination including skin prick testing.
Smoking was associated with a high prevalence of chronic rhinitis in both men and women and a low prevalence of allergic rhinitis in men. These associations were dose dependent and remained when adjusted for a number of possible confounders in multiple logistic regression analysis. Prevalence of chronic rhinitis was lowest in nonsmokers and highest in very heavy smokers (18.5% vs 34.5%, P