Response to nonallergenic irritants in children with allergic and nonallergic rhinitis

Purpose: Nonallergenic irritants can aggravate the symptoms of rhinitis. We investigated the clinical responses of children with allergic rhinitis (AR) and nonallergic rhinitis (NAR) to nonallergenic irritants, and identified factors associated with these responses. Methods: Children with chronic rhinitis (n=208) were classified as having AR or NAR based on the presence of aeroallergen-specific IgE. Healthy controls (n=24) were recruited for comparison. The Allergic Rhinitis and its Impact on Asthma (ARIA) guidelines were used to classify patients, and their irritant score (0-21 points) and current symptom score (5-35 points) were measured. Subjects with irritant scores >3 and <3 were classified as having irritant and nonirritant rhinitis, respectively. Results: The mean age of enrolled subjects was 6.8 years (range: 1.8-16.0 years). The AR and NAR groups had similar irritant scores (P=0.394) and proportions of subjects with irritant scores >3 (P=0.105). Irritant score correlated positively with symptom score (P=0.005), and the proportion of subjects with irritant scores >3 was greater in children with moderate-severe rhinitis than in those with mild rhinitis (P=0.046). Multiple logistic regression analysis indicated that the presence of atopic eczema increased the risk for sensitivity to a nonallergenic irritant (aOR=2.928, 95% CI 1.567-5.473, P=0.001). Conclusions: Response to a nonallergenic irritant was useful for gauging the severity of rhinitis, but not for differentiating AR from NAR. AR and NAR patients with atopic eczema may increase nasal sensitivity to nonallergenic irritants.