Mortality rate and affecting factors in bronchiectasis patients: a 10-year retrospective cohort study from Turkey

BACKGROUND: Bronchiectasis is a heterogeneous respiratory disease with substantial variation in its clinical course. This study aimed to determine the all-cause mortality rate among hospitalized adults with bronchiectasis—the prespecified primary endpoint—and to evaluate secondary exploratory predictors including sputum microbiology and peripheral eosinophil counts. METHODS: We retrospectively analyzed 14,319 outpatients diagnosed with bronchiectasis (ICD-10 J47) at a tertiary care center between 2015 and 2024. Mortality analysis was restricted to 2,382 hospitalized adults. Demographic characteristics, comorbidities, hospitalization burden, sputum microbiology, and baseline eosinophil levels were assessed. Time-to-all-cause mortality was analyzed using a multivariate Cox proportional hazards model (confirmatory analysis). Associations involving microbiology and eosinophilia were evaluated as secondary exploratory endpoints. RESULTS: The 10-year crude mortality rate was 34.8%, higher in males and in patients ≥ 55 years. Independent predictors of increased mortality included male sex, older age, COPD, sequelae of tuberculosis, Pseudomonas aeruginosa infection, increased hospitalization number, and longer hospital stay. Pseudomonas aeruginosa was the most frequently isolated pathogen and was associated with recurrent hospitalizations and higher mortality. Hemoptysis was associated with better survival. Baseline eosinophilia (≥300 cells/µL) was independently associated with mortality, although the effect size was minimal (HR 1.003), indicating limited clinical impact. CONCLUSION: Bronchiectasis imposes a significant mortality burden, particularly among older males and patients with COPD overlap or Pseudomonas aeruginosa infection. Hemoptysis was associated with better survival, whereas peripheral eosinophilia showed only a minimal prognostic effect. These findings highlight the clinical heterogeneity of bronchiectasis and support a risk-stratified management approach focused on high-risk phenotypes.