Allergen-specific sensitization in asthma and allergic diseases in children: the study on farmers' and non-farmers' children

• Published in: Clinical and experimental allergy Vol. 35; no. 2; pp. 160 - 166
• Main Authors: Remes, S. T., Koskela, H. O., Iivanainen, K., Pekkanen, J.
• Format: Journal Article
• Language: English
• Published: Oxford, UK Blackwell Science Ltd 01.02.2005; Blackwell; Wiley Subscription Services, Inc
• Subjects: Adolescent; Agricultural Workers' Diseases - diagnosis; Agricultural Workers' Diseases - immunology; allergen; Allergens - immunology; Allergic diseases; Animals; Animals, Domestic; asthma; Asthma - diagnosis; Asthma - immunology; atopy; Biological and medical sciences; Case-Control Studies; Chi-Square Distribution; Child; children; cockroach; Cockroaches; Cross-Sectional Studies; Dermatophagoides; Environmental Exposure; epidemiology; farm; Female; Finland; Fundamental and applied biological sciences. Psychology; Fundamental immunology; Humans; Hypersensitivity - diagnosis; Hypersensitivity - immunology; Immunopathology; Lepidoglyphus destructor; Male; Medical sciences; pets; sensitization; skin prick test; Skin Tests; Finland; Human; pets; Immunopathology; Lung disease; Allergy; Prick test; Respiratory disease; Exploration; Epidemiology; Asthma; Atopy; Cockroach; Immunology; children; Bronchus disease; farm; Sensitization; skin prick test; Obstructive pulmonary disease; Farmer; Child; Allergen; Farming; Skin test
• ISSN: 0954-7894; 1365-2222
• DOI: 10.1111/j.1365-2222.2005.02172.x

Summary Background Farmers' children are less frequently sensitized to common allergens than the non‐farmers' children, but less is known about their sensitization to other allergens and its association with clinical diseases. Objective To examine the association of farm environment with atopic sensitization, allergic diseases, expression of allergen‐induced symptoms, and the importance of specific sensitization against ‘common’ (timothy, dog, cat, birch, Dermatophagoides pteronyssimus, mugwort) and ‘other’ (cockroach, horse, Lepidoglyphus destructor, cow) allergens for asthma and allergic diseases in children. Methods A cross‐sectional study including 344 farmers' and 366 non‐farmers' children aged 6–13 years in eastern Finland, using a self‐administered written questionnaire and skin prick tests against the above‐mentioned allergens. Results Farmers' children had less asthma and allergic diseases and were less often sensitized against common allergens than the non‐farmers' children. However, little difference was observed in sensitization against the other allergens between the farmers' (17.2%) and non‐farmers (14.5%) children [adjusted odds ratios (aOR) 1.11 (0.71–1.72)]. Being sensitized against only other allergens, without sensitization against common allergens, was unrelated to asthma or allergic diseases. Among the single allergens, sensitization against pets or pollen, or against horse or cow, had the strongest association with asthma, hayfever, and atopic eczema; no such association was seen in D. pteronyssimus, mugwort, cockroach, or L. destructor. Farmers' children had significantly less often symptoms of allergic rhinitis in contact with dog (aOR 0.32%, 95% confidence interval (CI) 0.15–0.67), cat (aOR 0.45, 0.22–0.88), or pollen (aOR 0.58%, 95% CI 0.37–0.90) than the non‐farmers' children. Conclusion Farm environment reduces the occurrence of asthma, allergic diseases, and atopic sensitization in children, and also the occurrence of allergen‐induced rhinitis. Remarkable differences were observed between single allergens in their association with allergic disease, stressing the importance of allergen selection when defining atopy in epidemiological studies.