Although clinically significant bronchiectasis (CS-Bx) has been recently defined for clinical trials (Aliberti, Lancet RM 2021), a validation of those criteria in a real-life scenario is still lacking.

We conducted a multicentre, cross-sectional study (The Steady State Signs and Symptoms - 4S study) across 9 Italian Bronchiectasis Programs in 2023-24 enrolling consecutive adults with radiologically and CS-Bx (according to the judgement of the attending physician). A comprehensive evaluation of signs and symptoms during stable state was performed. Patients were divided into adherent (A) or not adherent (B) to 2021 criteria for clinically significant bronchiectasis.

Among 357 patients (73.7% female, median age 67 yo) enrolled, 50.7% had cough daily or most days a week, 48.5% sputum production daily or most days a week, 33.6% fatigue, 18.8% weight loss, 17.6% night sweats, 10.6% fever or low-grade fever, 8.1% nocturnal respiratory symptoms, 6.2% significant exertional dyspnoea. 35.0% had a history of exacerbations. 45.9% belonged to Group A. A higher prevalence of patients in Group A was detected among patients undergoing daily physiotherapy compared to naïve patients (56.2% vs 40.5%, P=0.005). Among patients in Group B, 30.0% had either cough or sputum production most days a week, and 19.1% a history of exacerbations without daily sputum or cough. When compared to group B, patients in group A were more frequently males (33.5% vs 20.2%, P=0.004), more severe (BSI 6 [3-10] vs 4 [3-7], P=0.009) and more frequently infected by Pseudomonas (27.5% vs 10.5%, P<0.001).

Patients with CS-Bx have heterogeneous signs and symptoms and they often do not fulfil the 2021 criteria.