Development and Validation of Clinical Scoring System to Estimate Mucus Plug Presence in Asthma

Airway mucus plugs on chest computed tomography (CT) are increasingly recognized for their impact and potential as treatable traits. However, radiation exposure warrants reasonable patient selection.

To develop and externally validate a practical clinical score to predict CT-detected mucus plug presence in 2 asthma cohorts and to evaluate its association with clinical outcomes.

This multicenter retrospective analysis used clinical and CT data from adult patients with stable asthma. The primary outcome was mucus plug presence on CT. We identified independent predictors using multivariable logistic regression, derived a practical scoring system in the exploratory cohort, and validated it in an independent cohort.

The prevalence of mucus plugs was 50.8% (218 of 429) in the exploratory cohort and 76.5% (143 of 187) in the validation cohort. Age (A; maximum 2 points), body mass index (B; maximum 2 points), blood eosinophil count (E; maximum 2 points), fractional exhaled nitric oxide (N; maximum 1 point), and percent-predicted FEV₁ (F; maximum 2 points) were independently associated with the presence of mucus plugs. The derived score (ABENF score; maximum 9 points) showed good discrimination in both cohorts (cohort 1: area under the receiver-operating characteristic curve, 0.781, 95% CI, 0.742-0.820; cohort 2: area under the receiver-operating characteristic curve, 0.836, 95% CI, 0.783-0.889). The high-score group (ABENF score ≥4) had a shorter time to first exacerbation (P = .046) and higher sputum eosinophil percentage (P < .001) in the validation cohort.

The ABENF score could be a practical tool to estimate mucus plug presence, potentially supporting more selective CT use.