Exercise-induced bronchospasm (EIB) in relation to seasonal and perennial specific IgE in young adults

We investigated the relationship between exercise-induced bronchospasm (EIB) and specific IgEs for seasonal (S-IgE) and perennial (P-IgE) allergens. The study, outside the main pollen season, was conducted on 289 20–year-old soldiers, who completed a self-administered questionnaire. A total of 289 subjects had S-lgE and P-IgE measured. The population was divided into subjects with (n- 166) and without (n = 123) history of atopic diseases (HAD). Twenty-three of 289 subjects (8%) had asthma, 70 289 (24%) allergic rhinitis, and 92/289 (32%) atopic siblings. Measured EIB was found in 17/289 subjects (6%). They had significantly higher levels of S-IgE and P-IgE than those without measured EIB (respectively, P ≤0.01 and p ≤0.05). The odds ratios of having EIB were significantly increased in the entire population in relationship with an increase in both S-IgE and P-IgE (chi-square test for trend 9.4 and 12.7, P ≤0.002 and 0.001. respectively). Interestingly, this highly significant relationship remained true when considering only the no HAD group (chi-square test = 7.4 and 8.8. P ≤0.006 and 0.003, respectively). Outside the pollen season. EIB was highly related to the level of both specific seasonal and perennial IgEs in the total population and in the subjects without HAD. This suggests that even in young adults who have been asymptomatic throughout their life EIB appears to be closely linked to seasonal or perennial allergic diathesis as measured by specific IgEs.     

The relation of markers of fetal growth with asthma, allergies and serum immunoglobulin E levels in children at age 5–7 years

BACKGROUND: It has been suggested that fetal growth and maturation have an impact on the development of allergic diseases later in life. OBJECTIVE: To examine the association between measures of fetal growth and allergic disease in children at age 5-7 years. METHODS: As part of the German International Study of Asthma and Allergies in Childhood phase II surveys, a random sample of school beginners (n=1138) was examined in 1995. Data on anthropometric measures at birth and gestational age were obtained from maternal copies of birth records. Data on symptoms and doctor-diagnosed asthma, atopic dermatitis and hayfever were gathered by parental questionnaires. Atopic sensitization was assessed by serum IgE and skin prick tests to common aeroallergens. Children (741) had complete data for the explanatory variables of interest and were thus eligible for this analysis. Confounder-adjusted prevalence odds ratios (PORs) and means ratios with 95% confidence intervals (CI) were calculated using multiple logistic and linear regression. RESULTS: Birth weight and gestational age were positively associated with atopic sensitization (Ptrend=0.025 and 0.035, respectively). Children with a low birth weight relative to head circumference had a decreased risk of sensitization (POR 0.44, 95% CI 0.21-0.91; Ptrend=0.020). Moreover, total serum IgE increased with increasing birth weight (Ptrend=0.042). No consistent relationship was observed between markers of fetal growth and wheezing, doctor-diagnosed asthma, atopic dermatitis and hayfever. CONCLUSION: These data suggest that fetal growth and maturity are associated with atopic sensitization and total serum IgE levels in childhood.     

Allergy and autoimmune disease: a registry-based study

Background Allergy and autoimmunity are two potential outcomes of a dysregulated immune system, but the relationship between them is unclear. It has been hypothesized that they could be inversely associated because of different T helper cell reactivity patterns. However, both positive and negative associations have been reported. Therefore, our aim was to perform a large epidemiological study with a defined allergic disease cohort.
Methods During the years 1990–2002, 68 770 subjects were tested for total serum IgE (Total-IgE) and 72 228 were tested with Phadiatop for diagnosing allergic disease at Karolinska University Hospital, Stockholm, Sweden. This cohort was then linked with the Swedish Inpatient Registry 1968–2004 for a follow-up with regard to recorded discharges for 28 autoimmune diseases. We then used Cox regression and logistic regression to estimate the risk of autoimmune diseases in general in the allergy-tested subjects.
Results Subjects with positive Phadiatop test were at a statistically decreased risk of subsequent autoimmune disease in comparison with subjects with negative test; hazard ratio (HR): 0.80 [95% (Confidence interval) CI: 0.68–0.94). Prior autoimmune disease was associated with a decreased risk of positive Phadiatop test [odds ratio: 0.83 (95% CI: 0.72–0.96)] in comparison with negative test. Subjects with highly elevated Total-IgE were at a statistically increased risk of a subsequent autoimmune disease in comparison with subjects with normal levels [HR: 1.36 (95% CI: 1.09–1.70)], but no association was found between prior autoimmune disease and different Total-IgE levels.
Conclusion The study supports the hypothesis that allergy, defined as positive Phadiatop test, could be inversely related to autoimmune disease but this association is weak.     

Allergy to storage mites in asthmatic patients and its relation to damp housing conditions

The relation between allergy to house dust mites and allergy to storage mites was studied in 326 patients with bronchial asthma. A positive RAST to house dust mites was found in 24.5% and to storage mites in 7.4%. There was a close association between a positive RAST to house dust mites and a positive RAST to storage mites, and 91.6% had a positive RAST to both. Only 0.9% with a negative RAST to house dust mites had a positive RAST to storage mites, whereas the frequency was 27.5% in those with a positive RAST to house dust mites. Present occupation with exposure to storage mites was found in 20.8% with a positive RAST to storage mites. A positive RAST to both house dust mites and storage mites was significantly associated with anamnestic indicators of damp housing conditions. The close association between allergy to house dust mites and allergy to storage mites in this study is probably caused by a common environmental factor, i.e. damp housing conditions.     

Relationships of allergic sensitization, total immunoglobulin E and blood eosinophils to asthma severity in children of the EGEA Study

BACKGROUND: Although allergy is highly associated with childhood asthma, it is not well known if there is a relationship between the intensity of allergic sensitization and asthma severity. OBJECTIVE: The objectives of the study were to examine the relationships between several markers of allergy and asthma severity in asthmatic children included in the Epidemiological study on the Genetics and Environment of Asthma, bronchial hyper-responsiveness and atopy (EGEA). METHODS: The population comprised 216 asthmatic children below 16 years of age. Total IgE and blood eosinophil counts were measured and skin prick tests to 11 aeroallergens were performed. The intensity of the allergic sensitization was assessed by the number of positive skin prick tests and by skin weal sizes. Asthma severity was measured with four criteria: a clinical severity score, history of hospitalization for asthma, FEV1% predicted and inhaled steroid use in the last 12 months. RESULTS: Most of the children were sensitized to at least one aeroallergen (88.2%). Atopy was not related to the severity of asthma, except for a tendency for a more severe clinical score in non-atopic children. The type and intensity of the allergic sensitization were not associated with any criteria of asthma severity. Total IgE was significantly increased in children treated with inhaled corticosteroids and in children ever hospitalized for asthma (P-values 0.009 and 0.04, respectively). Eosinophil counts were not related to asthma severity. CONCLUSION: Our results suggest that severe childhood asthma may be related to a high level of total IgE but not to blood eosinophil counts. The lack of positive relationships between both atopy and the intensity of allergic sensitization with asthma severity supports the hypothesis of different risk factors being associated with asthma and with the severity of asthma.     

Allergy in severe asthma

It is well recognized that atopic sensitization is an important risk factor for asthma, both in adults and in children. However, the role of allergy in severe asthma is still under debate. The term ‘Severe Asthma’ encompasses a highly heterogeneous group of patients who require treatment on steps 4–5 of GINA guidelines to prevent their asthma from becoming ‘uncontrolled’, or whose disease remains ‘uncontrolled’ despite this therapy. Epidemiological studies on emergency room visits and hospital admissions for asthma suggest the important role of allergy in asthma exacerbations. In addition, allergic asthma in childhood is often associated with severe asthma in adulthood. A strong association exists between asthma exacerbations and respiratory viral infections, and interaction between viruses and allergy further increases the risk of asthma exacerbations. Furthermore, fungal allergy has been shown to play an important role in severe asthma. Other contributing factors include smoking, pollution and work‐related exposures. The ‘Allergy and Asthma Severity’ EAACI Task Force examined the current evidence and produced this position document on the role of allergy in severe asthma.     

Farming exposure in childhood, exposure to markers of infections and the development of atopy in rural subjects

BACKGROUND: Within the context of the hygiene hypothesis, we aimed to study the potential association between farming-related risk factors and Toxoplasma gondii (T. gondii) as well as Helicobacter pylori (H. pylori) seropositivity. METHODS: The study included questionnaire data and serum samples of 321 young adults living in a rural environment. Serum samples were analysed for specific IgE to a common panel of aeroallergens (SX1) as well as IgG against T. gondii and H. pylori. RESULTS: Regular contact with animal stables before the age of 3 years (odds ratio (OR) (95% confidence interval): 2.0 [1.0; 4.0]) and unpasteurized milk consumption at age 6 years (1.8 [1.0; 3.3]) were the strongest risk factors for T. gondii infection. None of the farming-related factors were significantly associated with H. pylori infection. Current consumption of raw farm milk was not significantly associated with H. pylori infection (2.1 [0.8; 5.3]). Regular contact with animal houses before the age of 7 years was the strongest predictor for atopy (0.49 [0.26-0.96]). The reduction in risk could not be further decreased by any other factor under consideration. After adjustment for animal house contact, the OR for atopy was decreased by raw milk consumption and H. pylori infection in an additive manner. CONCLUSION: Exposure to farming environments in childhood might predict T. gondii seropositivity in rural subjects. Nevertheless, the strongest predictor for atopy in rural subjects seems to be regular contact with farm animals. Whether T. gondii infection is an intermediate factor in the association between farm contact and atopy needs to be confirmed in larger studies.     

Allergy, asthma and markers of infections among Albanian migrants to Southern Italy

BACKGROUND: Studies of immigrants represent an useful tool to determine the relative relevance of environmental vs genetic factors in causing the reported rapid increase of the prevalence of sensitization and allergic diseases. METHODS: A total of 152 Albanian migrants to Southern Italy responded to a questionnaire based on the European Community Respiratory Health Survey (ECRHS) and 139 of them underwent skin prick test, and 61 serological assays for total IgE and IgG antibodies against Toxoplasma gondii (TG), herpes simplex virus 1 (HSV-1), hepatitis A virus (HAV) and Helicobacter pylori (HP). RESULTS: Reported asthma was rare (2/152; 1.3%) and reported nasal allergies rather frequent (24/152; 15.8%). Sensitization to common inhalant allergens occurred in 27/139 (19.4%) subjects. The frequency of skin sensitization to pollen (P = 0.003) and that of hay fever (P = 0.004) increased with the time spent in Apulia. All the 61 sera had antibodies against HAV, 59/61 (96.7%) against HSV-1, 48/61 (78.7%) against HP and 34/61 (55.7%) against TG. The prevalence of skin sensitization and hay fever symptoms were correlated to the duration of residence in Southern Italy. CONCLUSIONS: Data presented indicate that Albanian migrants to Italy, in spite of the low prevalence of allergic diseases and sensitization in their country of origin, manifest with time an increasing prevalence of sensitization to local allergens and nasal symptoms after immigration to Italy. This would suggest a permanent role of allergen exposure and lifestyle factors in influencing the appearance of sensitization and symptoms of allergic diseases.     

Venom allergy in adult Swedes: a population study

Hymenoptera allergies are a cause of considerable morbidity. However, deaths due to insect sting constitute a health hazard that can be minimized by effective therapy. We report the results of a study of 1815 men and women, aged 20–44 years and resident in three areas of Sweden. The prevalence of sensitization to the venom allergens of honeybees and wasps was assessed by RAST. Atopy and allergic diseases were considered possible risk factors for symptom development. Of the 1815 subjects, 1399 were randomly chosen from the general population. Of the random sample, 9.3% had specific bee or wasp IgE, 1.5% reported systemic reactions to bee or wasp stings, and 0.6% had both. Sensitization to bee or wasp correlated positively with atopy (odds ratio (OR) 2.0, confidence interval (CI) 1.4–2.8, P<0.0001), male sex (OR 1.8, CI 1.3–2.5, P<0.001), and age (OR 2.0, CI 1.4–2.8, P<0.01), and negatively to living in the northernmost of the three centers (OR 0.4, CI 0.3–0.7, P<0.001). Atopy was not found to be a risk factor for systemic reactions. We conclude that the prevalence of Hymenoptera allergy in Sweden is rather low when compared with other countries. Subjects with atopy seem to have an increased risk of becoming sensitized but do not develop systemic reactions more frequently than nonatopic subjects.     

The protective role of country living on skin prick tests, immunoglobulin E and asthma in adults from the Epidemiological study on the Genetics and Environment of Asthma, bronchial hyper-responsiveness and atopy.

BACKGROUND: Farming environment and traditional lifestyle seem to protect from childhood allergy. OBJECTIVE: The aim is to analyse the relationships of living in the country to asthma, positive skin prick tests and IgE among adults considering various windows of exposure over the life-span. METHODS: The study concerns 805 adults drawn from the Epidemiological study on the Genetics and Environment of Asthma, bronchial hyper-responsiveness and atopy (EGEA) (asthmatic cases, non-asthmatic controls, and parents of cases with and without asthma). Ever living in the country concerned 55% of the subjects. Early (beginning < 1 years), childhood (beginning < or = 16 years), prolonged (duration > or = 10 years) and current life in the country were studied. RESULTS: The results based on the case control and family components of the study show that IgE levels were significantly lower in those who ever lived in the country and in particular in those who lived for > or = 10 years. Positive skin prick tests (SPT) were significantly less prevalent in those who ever lived in the country and in particular in those with childhood (< or = 16 years) exposure. These associations remained independent of age, sex, smoking or asthma with IgE levels of 64 vs. 88 IU/mL; P = 0.004 for those ever living in the country vs. others and odds ratio for SPT positivity of 0.72 (95% CI [0.53-0.98]). In the more specific group with traditional mode of heating in childhood (use of wood) associations were stronger. The association with asthma, studied in parents of asthmatic probands showed that fathers, but not mothers, of asthmatics were significantly less often asthmatic themselves in relation to country living. CONCLUSION: Country life protects from asthma and adulthood allergy. The protective effect is not restricted to exposure in early childhood.     

Early life markers of atopy and asthma

Since early intervention could modulate the natural course of atopic disease, the availability of predictive markers is of considerable interest. As long as specific genetic markers are not available, early IgE-responses (hen's egg) together with a positive family history of atopy can be proposed as highly specific and predictive markers, which could define subgroups as potential candidates for secondary prevention.     

Serum IgE levels, atopy, and asthma in young adults: results from a longitudinal cohort study

To explore the natural history of asthma and its relation to allergic responses, we examined the relation between total serum IgE in early adulthood and a history of respiratory symptoms, airway hyperresponsiveness (AHR), and atopy during childhood. We studied 180 subjects aged 18–20 years who had been studied since the age of 8–10 years. We measured wheeze in the previous year by questionnaire, AHR by histamine inhalation test, atopy by skin prick tests, and serum IgE levels by immunoassay. Subjects with AHR in early adulthood had higher IgE levels (mean 257.0 IU/ml) than subjects with past AHR (mean 93.3 IU/ml) or with lifelong normal responsiveness (mean 67.6 lU/ml) ( P< 0.001). Subjects who had symptoms had higher IgE levels (mean 125.9 IU/ml) than those who were lifelong asymptomatic (mean 63.1 IU/ml) ( P< 0.001). Recent wheeze, AHR, and allergic sensitization all had a positive relation to serum IgE, but IgE was not more predictive of AHR than skin prick tests. The finding that young adults who are sensitized to common allergens are highly likely to have AHR even in the absence of symptoms is further evidence of the fundamental role of IgE-mediated responses in the natural history of AHR throughout childhood and into adulthood.     

Atopy in Norwegian and Russian adults: a population-based study from the common border area

Background: Several studies have concluded that atopy is more common in Western than in Eastern Europe. We aimed to study whether a similar difference exists between Norwegian and Russian adults living in geographically adjacent areas. Methods: A cross‐sectional population‐based study was performed in Sør‐ Varanger municipality (Norway) and in the cities of Nikel and Zapolyarny (Russia). The Russian cities are heavily polluted by sulfur dioxide from local nickel industry. In addition to questionnaire information, results on IgE sensitization (S‐Phadiatop, Pharmacia & Upjohn, Uppsala, Sweden) were obtained from 3134 Norwegian and 709 Russian participants. Results: A positive Phadiatop was found in 20.7% of the Norwegians (men 21.9%, women 19.7%) and in 27.5% of the Russians (men 35.7%, women 23.0%); the sex‐ and age‐adjusted relative risk of testing positive in Russia being 1.49 (95% CI 1.23–1.81). The Norwegian participants reported more atopic dermatitis and hay fever, although this difference was statistically significant only for atopic dermatitis in women. Conclusion: IgE sensitization was more common in Russia than in Norway, unlike findings from other east–west European studies. The Russians did not, however, report more atopic diseases. This discrepancy might reflect different awareness of allergies in the two countries and demonstrates the need for objective markers of atopy when comparing prevalence in different populations.     

Prospective study of laboratory-animal allergy: factors predisposing to sensitization and development of allergic symptoms

In a prospective study of laboratory technicians, selected indicators of allergy and atopy were studied in an attempt to determine predictors of laboratory-animal allergy (LAA). Laboratory technicians underwent spirometry, methacholine provocation tests, and blood sampling, and responded to a questionnaire during training and after 2 years' work. Among 38 laboratory-animal-exposed subjects, total IgE before exposure gave the best correlation ( P < 0.01; Mann-Whitney U-test) to reported symptoms caused by laboratory animals ( n = 8) at follow-up. The prevalence of atopy and allergic symptoms had increased in exposed technicians at follow-up, but this was also found among unexposed matched referents ( n = 36 pairs). One subject in the exposed group reported asthma before exposure, compared with seven at follow-up ( P < 0.05; Fisher's exact test). However, the prevalence of asthma had increased from two to six (not significant) also among unexposed technicians. There were no significant differences between the groups in any measured variable at follow-up. Among 43 subjects who later worked with laboratory animals, 21%, had a positive skin prick test for common allergens, as compared with 37% among 112 without animal exposure P = 0.06; x² test), suggesting selection for laboratory animal work.     

Early childhood environment related to microbial exposure and the occurrence of atopic disease at school age

BACKGROUND: There is a growing body of evidence that the early childhood environment with respect to day care attendance, older siblings, pet ownership, and early life airway infections may protect from developing atopic disease. Few studies have distinguished between atopic sensitization and symptoms, and none have evaluated independent contributions for all of these different environmental conditions. OBJECTIVE: Examine independent effects on atopic sensitization and symptoms of day care attendance, older siblings, pet ownership, and early infancy's airway disease. METHODS: A cross-sectional survey among 8-13-year-old school children with complete data for 1555 children. RESULTS: After adjustment for confounders, atopic sensitization occurred less frequently in children that had attended a day care centre (OR: 0.73, 95% CI: 0.55-0.98) or had a cat or dog before 2 years of age (OR: 0.78, 95% CI: 0.61-0.99). Having older siblings yielded a nonsignificant trend towards protection (OR: 0.88, 95% CI: 0.70-1.11). For symptoms, there was no relation with having older sibs, day care attendance and pet ownership, although there was a trend towards protection for the combination of atopy and symptoms. In contrast, children with doctors' treated airway disease before age 2, more frequently reported recent symptoms of wheeze, asthma, rhinitis, or dermatitis (all P < 0.05). CONCLUSION: Early life environmental exposure to day care, or pets may protect against atopic sensitization. Protection against symptoms only occurred if atopic sensitization was present as well.     

Meta-analysis of determinants for pet ownership in 12 European birth cohorts on asthma and allergies: a GA2LEN initiative

Background: Studies on pet ownership as a risk or protective factor for asthma and allergy show inconsistent results. This may be on account of insufficient adjustment of confounding factors. Aim: The objective of this study was to describe determinants of cat and dog ownership in European families with and without allergies. Methods: Within the EU‐funded network of excellence GA²LEN, we performed meta‐analyses with data from 12 ongoing European birth cohort studies on asthma and allergy. Each of the birth cohort studies enrolled between 485 and 4089 children. Pet ownership, allergic status (asthma, allergic rhinitis, eczema) of parents and siblings, parental education, access to ground floor, and number of people living at home were assessed by questionnaires. Results: Among the 25 056 families from seven European countries cats (14.9%) were more common than dogs (12.0%). Allergic family history significantly reduced the odds to own a cat (adjusted combined random‐effect OR 0.91; 95% CI 0.85–0.99), or dog (0.90; 0.86–0.94). A higher parental educational level had even more pronounced effects on cat (0.84; 0.71–0.98), and dog ownership (0.61; 0.54–0.70). Elder siblings reduced the odds to own cats, but not dogs. Convenient ground access significantly increased the odds, whereas crowding at home was not associated with cat or dog ownership. Conclusions: The chances to own a cat or dog were significantly reduced in allergic families, in parents with a higher educational level, and in homes without convenient ground access. In addition to parental allergies, social and housing factors should be considered as potential confounders in studies on pet exposure and allergic diseases.     

A disparity in the association of asthma, rhinitis, and eczema with allergen-specific IgE between Finnish and Russian Karelia

BACKGROUND: A substantial variation in the association of asthma, rhinitis and eczema with elevated serum allergen-specific immunoglobulin E (sIgE) levels between different populations has been reported. Here, we wanted to clarify whether these proportions are different in Finnish and Russian Karelia, and compared the ability of questionnaires, skin prick tests (SPT) and sIgE measurements to detect atopic conditions in these adjacent areas with different living conditions. METHODS: Randomly selected schoolchildren, aged 6-16 years, and their mothers from Finland (n = 344 children, 344 mothers) and Russia (427 and 284 respectively) participated. SPTs and sIgE measurements to common inhalant and food allergens were performed. The occurrence of asthma, rhinitis, eczema and related symptoms was assessed with an International Study of Asthma and Allergies in Childhood-based questionnaire. Correlation between SPT and sIgE was estimated using the Spearman correlation coefficient. RESULTS: The rate of positive sIgE results was significantly higher in Finland among both mothers and children. Seventy-seven per cent of Finnish children and 43% of Russian children with asthma were sIgE positive. The respective figures for hay fever were 94% and 67%, and for eczema 68% and 41%. This discrepancy was similar but of lower magnitude among mothers. The overall occurrence of asthma, rhinitis and eczema was very low in Russian Karelia. The correlation between SPT and sIgE results was generally good. CONCLUSION: Asthma, rhinitis and eczema in Russian Karelia are not only rare but also, to a large extent, have no sIgE component. Therefore, the ability of questionnaires to detect sIgE-mediated atopic conditions in this area of Russia is poor.