Epidemiological characterization of the intermittent and persistent types of allergic rhinitis

Background: A new classification of allergic rhinitis (AR) has been proposed by the allergic rhinitis and its impact on asthma (ARIA) workgroup. The validity of this new classification is still largely unknown, especially the extent to which it differs from the classical seasonal/perennial (SAR/PAR) classification, and how and whether intermittent and persistent types of AR, as defined by ARIA, differ from each other. Methods: Two-step cross-sectional, population-based, in six Western Europe countries; telephone interview followed by clinical diagnosis [including specific immunoglobulin E (IgE) measurements] in a selected subset. Results: Within the population with AR, 29% of the subjects had persistent AR. There was no association between the intermittent/persistent and the SAR/PAR classifications. Subjects with persistent AR had more severe symptoms, and higher rate of self-awareness and previous diagnosis of AR; they were also clearly distinct in their sensitization pattern and medication use. Conclusions: The classic types of SAR/PAR cannot be used interchangeably with the new classification of intermittent/persistent, as they do not represent the same stratum of disease. There is also evidence that the persistent type describes a distinct group with characteristics that differentiates them from intermittent AR. These results support the validity of the new ARIA classification.