Geographical variation in the prevalence of sensitization to common aeroallergens in adults: the GA(2) LEN survey.

BACKGROUND: Geographical variation in the prevalence of sensitization to aeroallergens may reflect differences in exposure to risk factors such as having older siblings, being raised on a farm or other unidentified exposures. OBJECTIVE: We wanted to measure geographical variation in skin prick test positivity and assess whether it was explained by differences in family size and/or farm exposure. We also compared prevalence in younger and older subjects. METHODS: Within the Global Allergy and Asthma European Network (GA(2) LEN) survey, we measured the prevalence of skin prick positivity to a panel of allergens, and geometric mean serum total immunoglobulin E (IgE), in 3451 participants aged 18-75 years in 13 areas of Europe. Estimated prevalence was standardized to account for study design. We compared prevalence estimates in younger and older subjects and further adjusted for age, gender, smoking history, farm exposure, number of older siblings and body mass index (BMI). RESULTS: Skin prick test positivity to any one of the measured allergens varied within Europe from 31.4% to 52.9%. Prevalence of sensitization to single allergens also varied. Variation in serum total IgE was less marked. Younger participants had higher skin prick sensitivity prevalence, but not total IgE, than older participants. Geographical variation remained even after adjustment for confounders. CONCLUSION: Geographical variation in the prevalence of skin prick test positivity in Europe is unlikely to be explained by geographical variation in gender, age, smoking history, farm exposure, family size and BMI. Higher prevalence in younger, compared to older, adults may reflect cohort-associated increases in sensitization or the influence of ageing on immune or tissue responses.

Prevalence of childhood asthma, rhinitis, and eczema in the Ternopil region of Ukraine--results of BUPAS study.

PURPOSE: The aim of the study was to estimate the prevalence of allergic diseases and symptoms in children of the Ternopil Region (Ukraine) and to explore their familial and environmental correlates. MATERIAL/METHODS: A cross-sectional study based on parental answers to a respiratory questionnaire based on ISAAC that included 4871 urban and rural children aged 6-14 years. Association of physician-made diagnoses and symptoms with environmental factors was examined by means of multivariate logistic regression. RESULTS: Increased risk of asthma (1.7%) was associated with urban residence (OR=1.8; p=0.04) and high parental education (OR=1.8; p= 0.02); spastic bronchitis (6.2%) with parental allergy (OR=1.3; p= 0.03); atopic eczema (6.2%) with younger age (OR=1.3; p=0.03), high parental education (OR=1.3; p=0.03), parental allergy (OR=1.4; p=0.02), tobacco smoke at home (OR=0.7; p=0.01) and household density (OR=0.6; p=0.001); diagnosis of unspecified allergic sensitization (11.8%) was related to high parental education (OR=1.2; p=0.03), parental employment (OR=0.8; p=0.02) and pets at home (OR=1.2; p=0.06). Symptoms of chest wheezing (11.5%) were related to tobacco smoke at home (OR=0.8; p=0.06). Attacks of dyspnea (7.3%) were related to parental allergy (OR=1.4; p=0.007), and type of heating (OR=1.7; p=0.04). Hay fever symptoms (5.7%) were related to younger age (OR=1.3; p=0,01) and urban residence (OR=2.0; p<0.0001). CONCLUSIONS: Except for asthma the prevalence of allergic diseases and symptoms as well as their correlates in children of Ternopil are similar to other estimates obtained in Eastern Europe. Low prevalence of asthma and relatively frequent occurrence of spastic bronchitis may suggest substantial underdiagnosis of childhood asthma.