WS06.01 Outcome measures for assessment of lung function – cross-sectional analysis of relationships between impulse oscillometry, electrical impedance tomography, multiple breath washout and spirometry

Objectives: Lung function assessment is key in CF care, but traditional outcome measures (OMs) such as FEV1 may not be sensitive enough the CFTR modulator era. LCI2.5 from multiple breath washout (MBW) a measure of small airway disease can lengthy advanced lung disease. Emerging OMs include impulse oscillometry (IOS) & electrical impedance tomography (EIT). Here we report results cross-sectional analysis relationships between IOS, EIT, MBW spirometry adults with CF. Methods: Cross-sectional baseline measurements spirometry, MBW, IOS and EIT stable patients (n = 68, 42male; mean age 41 y (SD 14.2); 64.5%pred 23.94); 18.78 5.34)) during randomised controlled trial. Pearson correlation coefficients (r), receiver-operator characteristic (ROC) curves intraclass (ICC) two separate test occasions were calculated (table). Results: R5-R20 showed significant moderate linear correlations LCI2.5, LCI5, M1M0, M2M0 Sacin FEV1, FVC FEF25–75 (r 0.43 to 0.62, p < 0.05). End expiratory (ΔEELI), negligible all tests –0.30 0.22, <0.05 0.57). It was possible construct ROC for ΔEELI due lack known “normal” having classified “abnormal” (<6.9). some parameters had good ability distinguish normal abnormal (>0.1 kPa) R5-R20. (≤90% predicted) FEV1. Test-retest reproducibility (ICCs 0.99 0.91). Conclusions: Our data indicate that there indices MBW. This relationship warrants further investigation larger datasets offers less effortful/time-consuming than respectively. did show any or thus useful this context. Table(abstract: WS06.01).Pulmonary 68)R5-R20End Expiratory Impedance (ΔEELI)LCI 2.5FEV1r (p value)ROC AUCr AUC*Unable calculate AUC accepted ΔEELI.r AUC**Unable LCI being (<6.9).r AUCIOS−0.62 (<0.05)0.92R5-R20−0.20 (0.11)−0.50 (<0.05)−−0.57 (<0.05)0.80R5−0.08 (0.50)−0.38 (<0.05)−−0.31 (<0.05)0.62R200.07 (0.57)−0.11 (0.37)−−0.61 (<0.05)0.98X50.18 (0.15)−0.44 (<0.05)−0.67 (<0.05)0.02Ax−0.19 (0.12)−−0.48 (<0.05)−−0.66 (<0.66)0.95Fres−0.15 (0.23)−0.46 (<0.05)−EITAEELI−0.20 (0.11)0.33−0.31 (<0.05)−−0.13 (0.29)0.42Global (GI)0.18 (0.15)0.670.14 (0.26)−0.21 (0.08)0.64MBWLCI 2.50.50 (<0.05)0.85−0.30 (<0.05)−−0.70 (<0.05)0.94LCI 50.52 (<0.05)0.84−0.29 (<0.05)−−0.71 (<0.05)0.92FRC−0.06 (0.65)0.49−0.10 (0.42)−0.01 (0.94)0.54M1M00.52 (<0.05)0.85−0.29 (<0.05)0.94M2M00.51 (<0.05)−−0.65 (<0.05)0.94Sacin0.43 (<0.05)0.69−0.26 (<0.05)−−0.38 (<0.05)0.71Scond0.09 (0.47)0.61−0.10 (0.44)−−0.13 (0.31)0.64SpirometryFEV1−0.62 (<0.05)0.100.21 (0.08)−−0.70 (<0.05)−FVC−0.60 (<0.05)0.170.22 (0.07)−−0.55 (<0.05)−FEF 25–75−0.53 (<0.05)0.130.17 (0.16)−−−0.72 (<0.05)P 0.05 statistically significant.Key – (r<0.3), (0.3 0.7).* Unable ΔEELI.** Open table new tab P significant. Key >0.7).