Italian Multicenter Cross-Sectional Study (AISAG) on light smoking and allergic diseases in adults.

Allergic rhinitis, allergic dermatitis, and food allergy are extremely common diseases and are frequently associated to each other and to asthma. Smoking is a potential risk factor for these conditions, but so far, results from individual studies have been conflicting. On the basis of these contradictory data in the literature we have carried out a multicenter cross-sectional study to evaluate the relationship between some allergic conditions and exposure or not to active light smoking. The study was carried out between May 2013 and November 2013 in 22 different Italian hospitals. Patients with respiratory and/or food allergy, and aged 18 years and over, visited at Allergy Outpatient Clinics, were invited to participate. A total of 1586 allergic patients (21.6% smokers) with a mean age of 39.2 years (standard deviation, SD = 15.1) were included. We demonstrated that the prevalence of tobacco smoking was higher in patients with food allergy and in asthmatic patients in stage III-IV. But no other statistical differences were found at univariate analysis. The sensitization patterns of non-smokers and smokers were similar. Furthermore, tobacco smoking was associated with higher risk of food allergy and lower risk of asthma. Moreover, tobacco smoking was an independent risk factor for persistent respect to intermittent rhinitis, and for asthma GINA stage III-IV with respect to stage I-II.