Comparing encounter-based and annualized chronic pseudomonas infection definitions in cystic fibrosis

Chronic Pseudomonas aeruginosa (Pa) infection is associated with increased morbidity and mortality in people with cystic fibrosis (CF). There is no gold standard definition of chronic Pa infection in CF. We compared chronic Pa definitions using encounter-based versus annualized data in the Early Pseudomonas Infection Control (EPIC) Observational study cohort, and subsequently compared annualized chronic Pa definitions across a range of U.S. cohorts spanning decades of CF care. We found that an annualized chronic Pa definition requiring at least 1 Pa + culture in 3 of 4 consecutive years (Green 3/4) resulted in chronic Pa metrics similar to established encounter-based modified Leeds criteria definitions, including a similar age at and proportion who fulfilled chronic Pa criteria, and a similar proportion with sustained Pa infection after meeting the chronic Pa definition. The Green 3/4 chronic Pa definition will be valuable for longitudinal analyses in cohorts with limited culture frequency. (c) 2021 European Cystic Fibrosis Society. Published by Elsevier B.V. All rights reserved.

Automated summary

Chronic Pseudomonas aeruginosa (Pa) infection is associated with increased morbidity and mortality in people with cystic fibrosis (CF). This study compares different definitions of chronic Pa infection and finds that an annualized definition requiring at least 1 positive culture in 3 of 4 consecutive years produces similar results to established encounter-based criteria. The findings suggest that this annualized definition is valuable for longitudinal analyses in cohorts with limited culture frequency.