Factors associated with frequent exacerbator's phenotype in non-cystic fibrosis bronchiectasis: a retrospective single centre analysis

Bronchiectasis is a heterogeneous disease with a variety of underlying etiologies. Acute exacerbation is defined as a sudden deterioration of respiratory symptoms."Frequent exacerbators"(FE) are characterized by a more severe disease course leading to a worsened quality of life and higher mortality risk. The aim of this study is to describe FE by finding associated factors in outpatient cohort followed at our Institution. FE are defined with history of >=3 exacerbations for year in previous 3 years and/or >= 1 hospitalizations. Clinical, radiological and microbiological variables were compared between FE and not FE. Statistical analysis was made using Mann-Whitney test for continuos or ordinal variables and Fisher exact test for categorical variables.A two-tailed p-value of < 0.05 was considered significant.109 patients were included (51.4% FE, 48.6% non-FE).FE were more symptomatic with higher frequency of cough (73% vs 26%, p<0.0001), daily sputum (68.7% vs 34.6%,p=0.001) and severe dispnea (27% vs 6%,p=0.03). Radiological involvement (presence of cystic bronchiectasis) was strongly associated with FE FE group (p=0.0002). Lung function impairment was significantly more frequent in FE with lower median values of FEV1 (p=0.0157). Previous bacterial infections were significantly associated to FE phenotype with correlation for Staphilococcus aureus (p=0.006), Pseudomonas aeruginosa (p=0.001) and Aspergillus (p=0.0445) previous infections. In conclusion, FE phenotype rapresents a large proportion of our cohort of patients and to identify the treatable traits of FE could avoid the progression of disease.