Rhinitis symptoms and IgE sensitization as risk factors for development of later allergic rhinitis in adults

Abstract

Background: Rhinitis symptoms and IgE‐sensitization often mismatch. Asymptomatic sensitization is an established risk factor for later rhinitis, whereas it is not clear whether rhinitis is a risk factor for later development of IgE‐sensitization. Objective: To investigate whether nonallergic rhinitis is a risk factor for later development of IgE‐sensitization in adults during an 8‐year follow‐up period, and whether asymptomatic sensitization is a risk factor for later development of rhinitis. Methods: In a population‐based study of 15–69 years olds in 1990, 734 subjects were re‐examined in 1998. On both occasions questionnaires on rhinitis symptoms were completed and serum IgE (against birch, grass, mugwort, cat, dog, and Dermatophagoides pteronyssinus) were determined (positive if ≥0.35 kU_A/l). Asymptomatic sensitization: positive IgE levels without any rhinitis symptoms. Nonallergic rhinitis: rhinitis symptoms and no sensitization. Results: Asymptomatic sensitization to pollens, pets, or house dust mite was significantly associated with onset of rhinitis symptoms, also when changing baseline cut‐off for sensitization to ≥0.1 or ≥0.7 kU_A/l. The 8‐year incidence of pollen‐related rhinitis was 15.1% and 2.6% in subjects sensitized and nonsensitized to pollens, respectively (odds ratio 6.1, 95% CI 2.3–16.0). Persistent or intermittent nonallergic rhinitis was not significantly associated with later sensitization, yet a positive trend for development was observed in nonallergic pollen‐related rhinitis. Conclusion: Asymptomatic sensitization but not nonallergic rhinitis was a significant risk factor for later development of allergic rhinitis.