Currently, there is ongoing
discussion regarding potential protective effects of exposure to pets during
early childhood on the development of atopic disorders in children later in
life. We used data from three consecutive cross-sectional surveys to study
the relationship between contact with dogs, cats and other pets, and
allergic diseases in schoolchildren 5-14 years of age. In three study areas
of the former East Germany, 7,611 questionnaires were received from 5,360
different children who were examined between 1992 and 1999 as school
entrants, or third- or sixth-graders. Allergic sensitization to common
aeroallergens (birch, grass, mite, cat) was assessed by specific serum
immunoglobulin E (IgE) concentrations [using radioallergosorbent testing (RAST)]
for 85% of the children. After adjustment for possible confounders, inverse
associations were found between contact with dogs in the first year of life
and lifetime prevalences of asthma [odds ratio (OR) = 0.68; 95% confidence
interval (CI): 0.43-1.08], hay fever (OR = 0.61; 95% CI: 0.39-0.95), eczema
(OR = 0.76; 95% CI: 0.61-0.94), itchy rash (OR = 0.76; 95% CI: 0.61-0.94),
and pollen sensitization (RAST
4: OR = 0.56; 95% CI: 0.38-0.82). These effects were more pronounced for
children with atopic parents. Similar associations were observed for current
contact with dogs. We identified no clear relationships for the other pets
(cats, rodents, birds), with the exception that children currently exposed
to cats were more likely to be sensitized against cats. In conclusion, this
study supports the hypothesis of a potential protective mechanism related to
dog exposure in early life, especially for children of atopic parents.
However, this association was found only for dogs and not for cats. |
