Systemic immune-inflammation index in predicting hospitalized bronchiectasis exacerbation risks and disease severity

Bronchiectasis is a common respiratory disease with neutrophilic inflammation being the predominant pathophysiology. Systemic immune-inflammation index (SII) is a simple and readily available biomarker being studied in various conditions including asthma, chronic obstructive pulmonary disease, and interstitial lung disease, but not in bronchiectasis. We aim to investigate the prognostic role of SII in bronchiectasis with this study.