ASSOCIATION OF SKIN-TEST REACTIVITY, SPECIFIC IGE, TOTAL IGE, AND EOSINOPHILS WITH NASAL SYMPTOMS IN A COMMUNITY-BASED POPULATION STUDY

Background: Skin prick tests and measurement of specific IgE are impor tant markers possible allergic causes of disorders of the upper respir atory tract. Objective: In this study we investigated the association of skin test reactivity and specific IgE positivity to five common aer oallergens separately and of total serum IgE and eosinophil count with nasal allergy symptoms in a random sample of the adult population in The Netherlands. Methods: A cross-sectional study was carried out in a sample of 2167 subjects, aged 20 to 70 years, stratified by age and g ender. Nasal allergy symptoms were differentiated into three categorie s: symptoms after exposure to indoor allergens only, symptoms after ex posure to outdoor allergens only, and symptoms after exposure to both indoor and outdoor allergens. Associations were investigated by multip le logistic regression analyses with adjustment for area of residence, gender, age, and smoking status. Results: Skin test and specific IgE reactivity to indoor and outdoor allergens were significantly related to their corresponding nasal symptom groups. Odds ratios increased wit h increasing number of positive skin test results or increasing levels of specific IgE to allergens in all three nasal symptom groups. For e ach allergen, a positive skin test result together with a positive spe cific IgE measurement were the strongest predictors of nasal symptoms. Sensitization to house dust mite was the most prevalent in our study population, whereas the association of skin test reactivity and specif ic IgE positivity with nasal symptoms was strongest for cat allergen. Skin test and specific IgE reactivity to Cladosporium species were not significantly related to the prevalence of nasal symptoms. Total seru m IgE was related to nasal symptoms only in subjects who reported symp toms in response to both indoor and outdoor allergens and only at high levels of IgE. Eosinophil count was associated with nasal symptoms in all nasal symptom groups. Conclusions: Our findings confirm the close relationship of skin test positivity with reported symptoms of nasal allergy in a general population. Specific IgE positivity also shows a close relationship with nasal symptoms in response to allergen exposur e in a general population. Skin testing and specific IgE measurement m ay be considered complementary to one another in diagnosing allergic r hinitis. Total IgE may be considered an indicator of greater dysregula tion of the immune system in atopic allergy. Eosinophil count is assoc iated with nasal symptoms, regardless of type and extent of nasal symp toms.