Assessing the change in body composition and lung function in adults with cystic fibrosis (CF) pre and post initiation of elexacaftor/tezacaftor/ivacaftor (ETI)

Abstract

Objectives: The introduction of ETI has resulted in an improvement in the nutritional status of adults with CF, but research on this topic remains limited [1]. This study aimed to assess the change in body composition and lung function after initiation of ETI. Method(s): A retrospective analysis of patients' electronic data at the start and up to four years after ETI initiation was completed. Weight, body mass index, fat percentage, fat mass and muscle mass were obtained from Tanita MC-780 reports. Predicted forced expiratory volume (FEV1) and forced vital capacity (FVC) were taken within 3 weeks of body composition analysis. Change in body composition was analysed using t-test and Pearson's correlation tests were run to determine whether these changes were associated with change in lung function using SPSS version 29. Result(s): A total of 12 patients were included (7 male). There was a statistically significant change in weight and muscle mass post ETI initiation. A significant change in the correlation coefficient was found between increasing muscle mass and improvements to FEV1 (r=0.607; p=0.048) and FVC (r=0.762; p=0.006). Conclusion(s): This study shows a change in body composition post ETI initiation and suggests that increasing muscle mass is associated with positive effects on lung function in adults with CF. This supports the use of body composition measurements in clinical practice. Further research with a larger patient cohort on the optimal muscle mass targets to support lung function would be useful. Reference: Hevilla F, et al. Nutrients. 2024 Sep 28;16(19):3293. Copyright © 2025