Background: We examined the year-to-year change in FEV1 for individuals and the overall cystic fibrosis population to better understand how individual trends may differ from population trends. Methods: We calculated individual yearly changes using the largest annual FEV1 percent predicted (FEV1%) measurement in 20,644 patients (6-45years old) included in the Epidemiologic Study of Cystic Fibrosis. We calculated yearly population changes using age-specific medians. Results: FEV1% predicted decreased 1-3 points per year for individuals, with maximal decreases in 14-15year olds. Population changes agreed with individual changes up to age 15; however after age 30, yearly population change approximated zero while individual FEV1% predicted decreases were 1-2 points per year. Conclusions: Adolescents have the greatest FEV1% predicted decreases; however, loss of FEV1 is a persistent risk in 6-45year old CF patients. Recognizing individual year-to-year changes may improve patient-specific care and may suggest new methods for measuring program quality.
- Annual trends
- Cystic fibrosis
- Pulmonary function
ASJC Scopus subject areas
- Pediatrics, Perinatology, and Child Health
- Pulmonary and Respiratory Medicine