Lung clearance index (LCI) is a biomarker of ventilation inhomogeneity. Data are scarce on its usefulness in daily practice for monitoring the effects of treatments in older children and adults with CF. In this French observational study of lumacaftor-ivacaftor, 63 of 845 patients (7.5%) had available LCI performed at baseline and at six (M6; n=34) or 12 months (M12; n=46) after lumacaftor-ivacaftor initiation. At inclusion, median [IQR] age was 16 years [13-17], ppFEV₁ was 72.8 [59.6-80.7], and LCI was 12.3 [10.3-15.0]. At both M6 and M12, no statistically significant LCI increases of 0.13 units or 1.34% (95% CI: -4.85-7.53) and 0.6 units or 6.66% (95% CI: -0.03-13.5) were observed. Discordant results between LCI and ppFEV₁ were observed in one-third of the patients. In daily practice, LCI monitoring in adolescents and young adults with moderate lung disease gives results that are more heterogenous than those reported in children with milder disease.

肺清除指数 (LCI) 是通气不均匀性的生物标志物。关于其在日常实践中用于监测年龄较大的儿童和成人 CF 治疗效果的数据很少。在这项关于 lumacaftor-ivacaftor 的法国观察性研究中，845 名患者中有 63 名 (7.5%) 在基线和 lumacaftor-ivacaftor 开始后 6 个月 (M6；n=34) 或 12 个月 (M12；n=46) 时进行了可用的 LCI。纳入时，中位 [IQR] 年龄为 16 岁 [13-17]，ppFEV ₁为 72.8 [59.6-80.7]，LCI 为 12.3 [10.3-15.0]。在 M6 和 M12 中，没有观察到 0.13 个单位或 1.34%（95% CI：-4.85-7.53）和 0.6 个单位或 6.66%（95% CI：-0.03-13.5）的统计显着 LCI 增加。LCI 和 ppFEV _{1之间的结果不一致}在三分之一的患者中观察到。在日常实践中，对患有中度肺病的青少年和年轻人进行 LCI 监测的结果比在患有轻度疾病的儿童中报告的结果更具异质性。