Prevalence of food allergy in asthmatic children under 18 years of age in Semnan-Iran in 2007-2008

It is shown that the prevalence of food allergy in asthmatic children is high and there is significant association between food allergy and use of cow's milk before one year of age, low birth weight, short breast feeding period, male gender, history of other allergies in the patient and close relatives, early age of initiation of symptoms and also introduction of complementary foods before six month of age.

Abstract

Introduction: Asthma is the most common chronic disorder in children and is more prevalent in children5-10 years of age. The prevalence of childhood asthma has increased in recent years. Food allergy has beenimplicated as a risk factor for asthma. In this study, we determined the prevalence of food allergy andassociated factors in asthmatic children less than 18 years of age.Materials and Methods: In this Cross-sectional study, we studied 298 asthmatic children less than 18 yearsof age in Semnan (Iran) in 2007-2008, who were diagnosed according to physical examination and history.Skin prick test was performed for all of participants and a questionnaire was filled out. Wheals of 3millimeter and flares of 10 millimeters larger than negative control was regarded as a positive test.Results: 35.9 %( 95% Confidence Interval: 30.5-41.3%) of asthmatic children showed sensitization to atleast one of the principal allergenic foods (wheat, rice, peanut, egg, soya and cow milk). Prevalence of foodallergy in asthmatic children under 18 years of age had significant association with gender, birth weight,history of other allergies, family history of allergy, type of coexistent allergy and age of initiation ofsymptoms, age of introduction of complementary feeding, consumption of cow milk before one year of ageand also duration of breast feeding( P<0.05).Conclusion: these finding showed that the prevalence of food allergy in asthmatic children is high. There issignificant association between food allergy and use of cow's milk before one year of age, low birth weight,short breast feeding period, male gender, history of other allergies in the patient and close relatives, early ageof initiation of symptoms and also introduction of complementary foods before six month of age. Thus, weshould have particular attention on food allergens in such kind of patients, until they outgrown their foodallergies. This is the optimum way for controlling asthma in these people.