Refractory and unexplained chronic cough in adults treated in a cough centre.

<bold>Background:</bold> Refractory (RCC) and unexplained chronic cough (UCC) are significant clinical challenges, impairing patients’ quality of life. However, defining RCC in routine practice remains imprecise. This study aimed to assess RCC and UCC prevalence among patients referred to our cough centre and to analyse RCC prevalence in relation to its definition. <bold>Methods:</bold> This cohort study included all patients diagnosed at our cough clinic between 2018-2022. The response to therapy was measured based on cough severity and cough-related quality of life (measured by the Visual Analogue Scale [VAS] and by the Leicester cough questionnaire [LCQ], respectively). RCC was defined as persistent cough, with none or minimal improvement (<30 mm reduction on the VAS) after ≥2 treatment attempts and with its severity >40/100 mm in VAS. <bold>Results:</bold> Of 202 patients (F 137/M 65; median age 59.5 yrs, IQR 46-68; median cough duration 48 months, IQR 24-120) treated for chronic cough, only three (1.5%) were diagnosed with UCC. Among 164 patients monitored for therapy response, 71 (43.3%) experienced a cough severity reduction of ≥30 mm (VAS), while 100 (61%) showed an improvement of >1.5 points (LCQ). Based on basic definition, RCC was diagnosed in 54 of 164 patients (32.9%). Applying stricter criteria (persistent severe cough (>40 mm in VAS), insufficient therapy response (<30 mm reduction in VAS, and<1.5 point improvement in LCQ), RCC would be diagnosed in 45 subjects (27%). <bold>Conclusions:</bold> RCC is common in patients referred to cough clinics. The prevalence of RCC differs slightly depending on the diagnostic criteria. It is necessary to clarify the definition of RCC used in routine practice. An ERS NeuroCOUGH CRC site