Risk factors for increased need for intravenous antibiotics for pulmonary exacerbations in adult patients with cystic fibrosis

Background: Pulmonary exacerbations (P Exs) are important in cystic fibrosis (CF). They are very common, and are associated with poor quality of life. P Exs are regarded as an important end point in clinical trials. Risk factors associated with increase in P Exs have not been examined at a large scale. This study investigates factors associated with P Exs in a large cohort of adolescent and adult patients. Patients and methods: This is a cross-sectional study on data collected in the South and West Regions in England in 2002. Patients aged 16 years and over were included. Data on age, gender, FEV 1 , body mass index (BMI), infection with Pseudomonas aeruginosa (Pa) and on CF-related diabetes were included in the analysis. P Ex was defined as an episode treated with IV antibiotics. Forward stepwise multiple regression analysis was performed with the number of P Exs being the independent variable. The rest of the variables were considered to be the dependent variables. Results: Data from 341 patients (194 female), mean age (SD), 24.9 (8.9) years were available. In 2002, a total of 599 P Exs were reported, median 1.00 range 0—16 P Exs. Using stepwise multiple regression analysis factors associated with increased number of P Exs were: infection with Pa ( t-value —5.0, P < 0.0001), FEV 1 , ( t-value —4.9, P < 0.0001) and diabetes mellitus, ( t-value —2.1, P = 0.04). Age, gender and BMI did not influence the annual number of exacerbations. Conclusions: In this study, risk factors for P Exs were found to be as follows: growth of Pa in the sputum, reduced FEV1 and CF-related diabetes mellitus. Chronic Respiratory Disease 2008; 5: 29—33