Bronchiectasis in patients with inflammatory bowel diseases - prevalence, predictors, and clinical characteristics.

Abstract

Background: Inflammatory bowel diseases (IBD) are known to be associated with bronchiectasis (BE). However, data on BE among patients with IBD (IBD-BE) is limited.

Research question: What are the prevalence, risk factors, and clinical characteristics of IBD-BE?

Study design and methods: This was a single center retrospective study including patients who visited an IBD unit at a tertiary center between 2022 and 2023. Data on prior chest CT scans was extracted. Radiologists blinded to clinical data analyzed all chest CT scans for BE. The overall prevalence of IBD-BE was estimated using multiple imputation analysis. Risk factors were analyzed in the whole cohort and after matching.

Results: 1637 patients with IBD were included, 254 had prior chest CT scans, of these, 30 (1.8% of the cohort) had BE. The estimated overall prevalence of IBD-BE was 5.17% (95% CI 3.60-8.22%). Chest cuts of available abdominal CT scans (n=1048) were also analyzed identifying 19 additional cases of IBD-BE, resulting in a minimal prevalence of 3%. Ulcerative colitis, prior IBD-related surgery, and extra-intestinal manifestations (EIMs) were risk factors for IBD-BE. Of patients with chest CT scans, 63% had evidence of BE their prior abdominal CT scans, and 70% had relevant respiratory symptoms. Despite this, most did not see a pulmonologist nor received BE-related therapy. Clinical characteristics and outcomes were similar to patients with non-IBD-related BE.

Interpretation: This study shows a relatively high prevalence of IBD-BE. The low rates of BE-directed therapy and pulmonology referral indicate the need for a higher degree of suspicion and timely referral.