Loss of smell as a clinical marker of severe asthma and its association with upper airway inflammatory diseases

Asthma is frequently associated with rhinitis and chronic rhinosinusitis (CRS) while severe asthma is more associated with CRS with (CRSwNP) than without (CRSsNP) nasal polyps. Loss of smell (LoS) is also associated with CRS, mainly with CRSwNP. We aimed to assess loss of smell as a clinical marker to discriminate CRS from rhinitis and severe from non-severe asthma. In a cross-sectional multicentric study, asthmatic patients (N=383) were evaluated by pulmonologists and ENT specialists using GINA, ARIA, and EPOS definitions. LoS was evaluated by severity [VAS scale, 0-100mm, median (IQR, Inter-Quartil Range)] and by prevalence of anosmia (hyposmia VAS >0-70mm, anosmia VAS >70mm). LoS was present in 55.4% of asthmatics (hyposmia 41.5%, anosmia 14.9%). LoS was more severe [22mm (0-75), p