Persistence of lung hyperinflation and small airway dysfunction in school-aged children with cystic fibrosis treated with elexacaftor–tezacaftor–ivacaftor: results from the real-world MODUL-CF study
Source: PubMed Central Open Access, NCBI / U.S. National Library of Medicine
Background Trapped gas (TG) and ventilation inhomogeneity (VI) are early markers of altered small airway function (SAF) in cystic fibrosis (CF) lung disease. The evolution of these markers in children with CF (chCF) treated with elexacaftor–tezacaftor–ivacaftor (ETI) remains poorly understood. Using data from multiple breath washout (MBW) and body plethysmography (pleth) from a national, real-world cohort of school-aged chCF, we tested the hypothesis that VI and TG do not consistently return to normal levels following ETI therapy. Methods Data from MBW and pleth tests were collected from seven centres prior to ETI initiation (month 0 (M0)), after a year of treatment (M12) and at M6 (when available). Analyses were conducted to assess the evolution of per cent predicted (pp) residual volume (ppRV), total lung capacity (ppTLC) and the ppRV/TLC ratio, as well as the difference between pp functional residual capacity (ppFRC)and ppFRCas markers of TG. Global and regional VI indices were compared to those of age- and sex-matched healthy controls. Results A total of 192 chCF aged from 6 to 18 years at ETI initiation underwent MBW at M0 and M12. Significant reductions were observed in ppRV, ppTLC, ppRV/TLC and TG. However, 28% of the chCF cohort had ppRV/TLC values >120% at M12. MBW-derived outcomes improved significantly, but 51.9% of the cohort had lung clearance index (LCI) values at M12 that had not returned to healthy control levels. Conclusion ETI significantly improved SAF. How
Abstract
Background Trapped gas (TG) and ventilation inhomogeneity (VI) are early markers of altered small airway function (SAF) in cystic fibrosis (CF) lung disease. The evolution of these markers in children with CF (chCF) treated with elexacaftor–tezacaftor–ivacaftor (ETI) remains poorly understood. Using data from multiple breath washout (MBW) and body plethysmography (pleth) from a national, real-world cohort of school-aged chCF, we tested the hypothesis that VI and TG do not consistently return to normal levels following ETI therapy. Methods Data from MBW and pleth tests were collected from seven centres prior to ETI initiation (month 0 (M0)), after a year of treatment (M12) and at M6 (when available). Analyses were conducted to assess the evolution of per cent predicted (pp) residual volume (ppRV), total lung capacity (ppTLC) and the ppRV/TLC ratio, as well as the difference between pp functional residual capacity (ppFRC)and ppFRCas markers of TG. Global and regional VI indices were compared to those of age- and sex-matched healthy controls. Results A total of 192 chCF aged from 6 to 18 years at ETI initiation underwent MBW at M0 and M12. Significant reductions were observed in ppRV, ppTLC, ppRV/TLC and TG. However, 28% of the chCF cohort had ppRV/TLC values >120% at M12. MBW-derived outcomes improved significantly, but 51.9% of the cohort had lung clearance index (LCI) values at M12 that had not returned to healthy control levels. Conclusion ETI significantly improved SAF. However, not all outcome measures returned to normal, indicating residual lung disease in some chCF. Shareable abstract ETI improves ventilation inhomogeneity and reduces gas trapping without returning these indices to normal values, indicating residual lung disease, even in young children https://bit.ly/4iMBZJG short abstract-1