RESUMO
Asthma is one of the most prevalent chronic diseases in Spain. In 2019, the Spanish Society of Allergology and Clinical Immunology (SEAIC), the Spanish Society of Primary Care Physicians (SEMERGEN), the Spanish Society of Family and Community Medicine (semFYC), the Spanish Society of General and Family Physicians (SEMG) and the Spanish Society of Pulmonology and Thoracic Surgery (SEPAR) drafted a document laying down the criteria for referral and action guidelines in the diagnosis, control and monitoring of the asthmatic patient to facilitate ongoing care and improved attention in every setting. The new circumstances derived from the Covid-19 pandemic have demanded that some of the recommendations of the previous edition be updated and adapted to the new healthcare situation.
RESUMO
OBJECTIVE: The "united airway disease" concept is based on the bidirectional interaction between asthma and rhinitis. The aim of this study was to determine the relationship between upper airway diseases and bronchial hyperresponsiveness (BHR), as well as their association with the fractional concentration of exhaled nitric oxide (FeNO) and atopy in patients with persistent symptoms suggestive of asthma requiring methacholine challenge testing (MCT) to confirm asthma diagnosis. METHODS: A cross-sectional prospective study was carried out in adult patients with persistent asthma-like symptoms and negative bronchodilator testing. FeNO and MCT were performed in all patients. Asthma was confirmed based on the presence of suggestive symptoms and MCT results. Associated upper airway diseases included allergic rhinitis, nonallergic rhinitis, chronic rhinosinusitis with nasal polyps (CRSwNP), and aspirin-exacerbated respiratory disease (AERD). RESULTS: The study included 575 patients; asthma was confirmed in 32.3%, and FeNO values ≥ 50 ppb were found in 27% of the patients. Elevated FeNO was significantly associated to AERD. The prevalence of atopy in asthma patients was 86.6%. Atopy was present in 90.4% of patients with asthma and FeNO levels ≥ 50 ppb. A significant association was found between AERD, asthma, and FeNO ≥ 50 ppb. CONCLUSIONS: Patients with symptoms suggestive of asthma but negative bronchodilator testing are commonly seen in usual practice. In this population, the association of high FeNO levels and BHR to atopy, as well as to AERD, suggests the presence eosinophilic inflammation in both the upper and lower airways and supports the "one airway" hypothesis.