Early cat ownership and the risk of sensitization and allergic rhinitis in Ligurian children with respiratory symptoms

Background: Studies on the role of cat ownership in the development of allergy have lead to conflicting results, probably owing to heterogeneity of the populations evaluated. Objective: To evaluate the possible effect of cat ownership on the frequency of sensitization and asthma or rhinitis in children living in Liguria, Italy, who attended a pediatric clinic for respiratory symptoms. Methods: We enrolled 269 consecutive school-aged children in 12 months. Sensitization to aeroallergens by skin prick testing and the presence of respiratory symptoms (ie, asthma and rhinitis) were evaluated. To analyze the role of different independent variables in association with respiratory symptoms and sensitization, a multiple logistic regression analysis was performed. Results: Of 269 children, 81 were exposed to cats at home in the first 2 years of life (early cat owners), 65 after the first 2 years of life (late cat owners), and 123 never (never cat owners). Early cat ownership was significantly associated with a lower risk of cat sensitization compared with never cat ownership (adjusted odds ratio [ORadj], 0.32; 95% confidence interval [CI], 0.14-0.74; P = .0 1). Early cat ownership was also associated with a significantly lower risk of allergic rhinitis than late cat ownership (ORadj, 0.43; 95% CI, 0.22-0.85) or never cat ownership (ORadj, 0.51; 95% CI, 0.28 -0.92). No differences in the frequency of asthma were found among the 3 groups (P =.74) Conclusions: Cat ownership in early childhood can play an important role in preventing sensitization to cat and in lowering the frequency of allergic rhinitis, at least in children with the characteristics of the population studied. Ann Allergy Asthma Immunol. 2005;94:561-565.