Asthma is more frequently associated with non-allergic than allergic rhinitis in Portuguese patients* Olga Lourenço 1 , Ana Mafalda Fonseca 1 , Luís Taborda-Barata 1,2 1 CICS, Health Sciences Research Centre, University of Beira Interior, Covilhã, Portugal 2 Cova da Beira Hospital, Covilhã, Portugal *Received for publication: April 2, 2008; accepted: September 24, 2008 INTRODUCTION Rhinitis is a symptomatic disorder of the nose characterized by nasal blockage/congestion, rhinorrhea, itching and sneezing. Underdiagnosis is frequent as the disease is often trivialized, despite important impairment in the quality of life, increased medical costs and decreased school and work productivity. The majority of rhinitis cases generally start in childhood or adolescence in individuals responding to common aeroaller- gens and are mediated by immunoglobulin E (IgE) (allergic rhinitis or AR) (1) . AR is diagnosed by history and examination backed up by specific allergy tests (2) . Other patients develop non allergic forms of rhinitis, such as idiopathic rhinitis, hormonal rhinitis, food induced rhinitis, or drug induced rhinitis (non-allergic rhinitis or NAR) (3). NAR includes a number of heterogeneous nasal conditions, in their majority poorly defined in terms of their underlying mecha- nisms, and with multifactorial aetiology (4) . Unlike AR, there are no specific diagnostic tests for NAR. The diagnosis is pri- marily made by excluding allergy related features and infec- tious causes, as well as by assessing history of reactions to spe- cific irritant/toxic triggers. In addition, the presence of nasal and blood eosinophilia as well as hormonal status (mainly estrogens) should be analysed. Furthermore, NAR can also contribute to rhinitis symptoms in atopic patients, creating a “mixed” phenotype (3) . Based on the time of exposure to allergens, allergic rhinitis has been classified as seasonal allergic rhinitis (SAR), also known as hay fever, and perennial allergic rhinitis. SAR was associated with outdoor allergens, such as pollens, and perennial rhinitis was associated with indoor allergens, such as dust mites, moulds, and animal dander. As this classification was regarded as insufficient, the revised classification adopted by Allergic Rhinitis and its Impact on Asthma (ARIA) divides rhinitis according to frequency and duration of symptoms into “inter- mittent” and “persistent”, and according to severity (based on symptoms and quality of life) into “mild” or “moderate/severe” (4) . The prevalence of rhinitis is increasing woldwide (5) , and the estimated prevalence in Portuguese adults aged between 20 Background: Rhinitis prevalence is increasing worldwide and is frequently associated with asthma, for which it is a risk factor. The aims of the study were to characterise the adult popu- lation with rhinitis attending the Cova da Beira Hospital Allergy Clinic, and to assess the rela- tionship between rhinitis and asthma. Methods: In total, 686 patients were characterised by clinical history and anterior rhinoscopy, and classified according to international guidelines. Atopy was determined by skin prick testing to aeroallergens and quantification of specific IgE. Results: Seventy two percent of patients had allergic rhinitis (AR), and 28% had non-allergic rhinitis (NAR). NAR was more frequently associated with older age, perennial symptoms and female gender. NAR patients more frequently had bronchial asthma. In addition, more NAR than AR patients also had drug allergy, pharyngitis, sinusitis and urticaria. AR patients with nasal polyps more frequently had asthma. Grass pollen and mites were the major sensitisers for AR patients. Sensitisation profiles were not significantly different between urban- and rural- based AR patients. Conclusions: Asthma was more frequently associated with non-allergic than with allergic rhini- tis. The two types of rhinitis did not differ in clinical severity. Although sensitisation profiles were not different between the urban and rural patients, allergic rhinitis prevalence was higher in urban patients. Key words: allergens, rhinitis, human, prevalence SUMMARY ORIGINAL CONTRIBUTION Rhinology, 47, 207-213, 2009