Longitudinal bacterial prevalence in cystic fibrosis airways: Fact and artifact.

Background: Opportunistic bacterial infection is a hallmark of cystic fibrosis (CF) lung disease and early mortality. Poorly characterized prevalence changes have accompanied two decades of health improvements, with CFTR modulators likely to further affect infection epidemiology.
Methods: Bacterial prevalence change trends across birth cohorts were assessed with linear regression using 2001-2019 US CF Foundation Patient Registry data. Informative missingness was assessed, as was age-to-age infection status.
Results: Bacterial prevalence constantly changed from 2001 to 2019, with changes differing across birth cohorts. Informative censoring affected prevalence change for some organisms. Age-to-age infection status changes were greater than net changes in bacterial prevalence and varied by age.
Conclusions: CF infection epidemiology changed over two decades and will continue to do so. Understanding how modulators affect infection epidemiology will require creative designs for longitudinal prevalence change studies emphasizing prevalence changes independent of effects on lung biology.
Competing Interests: Declaration of Competing Interest The authors have no competing interests relative to this content to report. MWK received salary support to his institution from the Cystic Fibrosis Foundation and the National Institutes of Health (UL1TR002548). JJL received salary support from the Cystic Fibrosis Foundation (CAVERL22AB0).
(Copyright © 2023 European Cystic Fibrosis Society. Published by Elsevier B.V. All rights reserved.)