BackgroundLittle is known about risk factors for chronic and mucoid Pseudomonas aeruginosa (Pa) infection in cystic fibrosis (CF) adults, and whether the prevalence is changing.MethodsWe employed a retrospective cohort to analyze data from a single adult CF center (2002 to 2012). Regression models were used to assess independent predictors and change in prevalence of chronic and mucoid Pa infection over time.ResultsThe odds ratio of mucoid Pa infection was significantly less in individuals with better baseline lung function (OR 0.84,95%CI:0.77–0.92) and those diagnosed after the age of 25 (OR 0.21, 95%CI:0.05–0.95). The prevalence of chronic Pa and mucoid Pa decreased during the time interval. After adjusting for confounders, the observed decrease in chronic and mucoid Pa between 2002 and 2012 was no longer significant.ConclusionsThe prevalence of chronic and mucoid Pa is decreasing. Larger studies are needed to confirm these regional trends and their significance.Electronic supplementary materialThe online version of this article (doi:10.1186/s12890-016-0333-y) contains supplementary material, which is available to authorized users.