Abstract
Introduction. Atopic sensitization increases the risk of asthma. Generally, the presence of IgE antibodies (IgE-ab) to furry animals represent a risk factor for developing asthma in temperate areas, while IgE-ab to mites is the main risk factor in tropical and sub-tropical areas.
Aim. To study patterns of sensitization and the risk of asthma among adults.
Methods. In the West Sweden Asthma Study a questionnaire targeting asthma issues were sent to 30 000 randomly selected subjects aged 16-75 years. Of the 18 081 responders, a randomly selected sample of 2000 subjects and all reporting asthma, further 1536 subjects, were invited to detailed clinical examinations. Sera were received from 924 subjects with a diagnosis of asthma and from 1011 without, and these 1935 subjects were selected for this study. Sera were analyzed for IgE-ab using three allergen panel tests including inhalant and food allergens (ImmunoCAP). Samples with a level of IgE >0.35 kUA/l were analyzed for IgE-ab against each individual allergen included in the test.
Results. The risk of being sensitized was significantly higher in the asthma group for the 21 allergens tested (p<0.05). The risk was highest for individuals sensitized to furry animals (risk ratios 4,5-7,9). The level of IgE-ab was also significantly higher in the asthma group (p<0.0001) and 45% of the sera were triple positive to dog, cat and horse compared to 22% in the control group. The risk was lower for other allergens tested, including pollen, mites and foods (risk ratios 2,4-3,8).
Conclusion. Sensitization, particularly to furry animals, appears in this large sample of adults from West Sweden to be a major risk factor for asthma.
- © 2014 ERS