TY - JOUR T1 - The reproducibility and responsiveness of the lung clearance index (LCI) in bronchiectasis JF - European Respiratory Journal JO - Eur Respir J VL - 44 IS - Suppl 58 SP - P2572 AU - L.J.F. Grillo AU - S. Irving AU - J.C. Davies AU - A. Bush AU - D. Bilton AU - R. Wilson AU - M.R. Loebinger Y1 - 2014/09/01 UR - http://erj.ersjournals.com/content/44/Suppl_58/P2572.abstract N2 - Background: There are limited clinical outcome markers in non CF bronchiectasis (NCFBx). Lung clearance index (LCI) provides an assessment of peripheral airway function, and is a sensitive measure in cystic fibrosis. We assessed the reproducibility and responsiveness of LCI in stable and exacerbating NCFBx patients. Methods: 25 stable outpatients and 27 exacerbating inpatients were recruited and underwent LCI and lung function on 2 separate occasions. Exacerbating patients were tested at the beginning and end of 10 days IV antibiotics (IVABx). All exacerbating patients improved clinically and were discharged. Data is presented as median (range) and comparisons made using Mann Whitney U and Wilcoxon Signed Rank tests. Results: LCI was reproducible between visits in stable patients (Intraclass Correlation Coeff 0.915 (95% CI 0.76,0.97, p=0.001, n=19)).There was no significant difference (p=0.81, n=23) in LCI between stable (11.3(6.9-22.8)) and exacerbating (12.6(6.9-19.7)) patients, or between paired values at start (12.6(6.9-19.7)) and end (12.4(7.2-21.2)) of IVABx (p=0.296, n=21). FEV1% (68.6(33.4-124.9) v 52.5(18-110) p=0.02) and FVC% (93.8(63.4-143.7) v 74(17-134) p=0.002) were different in stable and exacerbating patients. In addition, unlike LCI, these values did significantly improve in exacerbating patients with IVABx (FEV1: 52.5(18-110) v 57.5 (23-123), p=0.007; FVC 74(17-134) v 84.2(24-140), p=0.002). No significant changes were seen for MEF. Conclusion: LCI is reproducible in stable NCFBx, but is unresponsive to IV antibiotics leading to clinical and spirometric improvement in this group of relatively severe NCFBx patients, in whom it is thus unlikely to be a useful clinical tool. ER -