Background: No large studies in adults has examined geographical variation in the prevalence of nasal allergy/allergic rhinitis in adults or considered the proportion of reported nasal symptoms on exposure to allergen attributable to atopy. The aim of this report was to describe the geographic distribution of subjects with nasal symptoms who are sensitized as determined by skin prick tests, using data from the European Community Respiratory Health Survey I.
Methods: Information on the presence of nasal allergy, nasal symptoms on exposure to allergen and atopy using skin prick tests was collected from 15,394 adults aged 20-44 years living in 35 centres in 15 countries. Age sex standardized prevalence of symptoms and the attributable fraction of IgE sensitization for nasal symptoms on exposure to allergen were determined.
Results: The age-sex standardized prevalence of nasal allergy ranged from 11.8% in Oviedo (Spain) to 46.0% in Melbourne (Australia). The prevalence of atopic nasal allergy ranged from 4.6% in Oviedo to 31.8% in Melbourne (analysis limited on 12,566 subjects). The median attributable fraction for atopy on nasal symptoms on exposure ranged between 12.8% and 65.9% (median 27.2%).
Conclusion: In the general population there is a wide variation in the prevalence of nasal allergy in young adults. Many subjects complaining from nasal symptoms on exposure to allergen are not atopic.