The BSI predicts future risk of hospitalization and mortality in people with bronchiectasis, combining clinical, imaging, and microbiology factors into a single score.
Low risk of future exacerbations/mortality.
Intermediate risk.
High risk.
Certain bacteria — especially Pseudomonas aeruginosa — are associated with more frequent exacerbations and worse outcomes in bronchiectasis, so their presence meaningfully raises risk.
Roughly: 0–4 is low risk, 5–8 is intermediate, and 9 or higher is high risk of future exacerbations, hospitalization, and mortality.
It stratifies prognosis to guide monitoring intensity, airway-clearance and eradication strategies, and how aggressively to manage a patient's bronchiectasis.
Recent hospital admission and older age contribute the most points, reflecting their strong association with poor outcomes.