Exposure to pets, and the association with hay fever, asthma, and atopic sensitization in rural children
- 11 October 2004
- Vol. 60 (2), 177-184
- https://doi.org/10.1111/j.1398-9995.2004.00645.x
Abstract
Background: An increasing number of studies report pet exposure to be associated with lower risk of asthma and allergies. This ‘protective pet effect’ has been suggested to result from a modified T‐helper (Th)2‐cell response, or because of increased microbial load in homes where pets are kept. We examined the associations between pet contact and the occurrence of asthma and allergies in children of the rural Allergy and Endotoxin (ALEX) population, taking farm animal contact, endotoxin and cat allergen levels in mattress dust into account. Methods: Information about contact with pets and farm animals, asthma and allergy were collected for 812 children by a standardized parents’ questionnaire and an interview. Mattress dust endotoxin and cat allergen levels as well as specific IgE and IgG4 antibodies to Fel d1 were determined. Results: Current contact with dogs was inversely associated with diagnosed hay fever (OR 0.26, 95% CI 0.11–0.57), diagnosed asthma (OR 0.29, 95% CI 0.12–0.71), sensitization to cat allergen (OR 0.48, 95% CI 0.23–0.99) and to grass pollen (OR 0.55, 95% CI 0.33–0.94), but not with increased IgG4 levels. Early and current contact with cats were associated with reduced risk of wheezing (OR 0.48, 95% CI 0.23–1.00, and OR 0.49, 95% CI 0.26–0.92, respectively) and grass pollen sensitization. Adjustment for farm animal contact but not for endotoxin and cat allergen exposure attenuated these associations and the effect of pet was stronger among farmers’ children. Conclusion: Although pet exposure was very frequent in this rural population, the inverse relation between current dog contact, asthma and allergy was mostly explained by simultaneously occurring exposure to stable animals or was restricted to farm children. In addition, a subtle form of pet avoidance may contribute to the protective effect of pet.Keywords
This publication has 28 references indexed in Scilit:
- Which factors explain the lower prevalence of atopy amongst farmers' children?Clinical and Experimental Allergy, 2003
- Exposure to pets and atopic dermatitis during the first two years of life. A cohort studyPediatric Allergy and Immunology, 2002
- Exposure to endotoxin decreases the risk of atopic eczema in infancy: A cohort studyJournal of Allergy and Clinical Immunology, 2001
- Dog exposure in infancy decreases the subsequent risk of frequent wheeze but not of atopyJournal of Allergy and Clinical Immunology, 2001
- Exposure to farming in early life and development of asthma and allergy: a cross-sectional surveyThe Lancet, 2001
- Systematic review: Exposure to pets and risk of asthma and asthma-like symptomsJournal of Allergy and Clinical Immunology, 2001
- Austrian children living on a farm have less hay fever, asthma and allergic sensitizationClinical and Experimental Allergy, 2000
- Prevalence of hay fever and allergic sensitization in farmer's children and their peers living in the same rural communityClinical and Experimental Allergy, 1999
- International Study of Asthma and Allergies in Childhood (ISAAC): rationale and methodsEuropean Respiratory Journal, 1995