Factors affecting progression of lung disease among patients with cystic fibrosis

<b>Aim:</b> To investigate the role of different types of bronchial infection and respiratory symptoms upon lung function decline. <b>Methods:</b> 89 children and adults with CF (mean (SD) age: 11.71 (6) years) performed 1340 serial Multiple Breath Washout (MBW) tests and 980 spirometries over a 5-year period. Respiratory symptoms (cough, sputum, nasal congestion) and Pulmonary Exacerbations (PEx) were recorded. Pseudomonas Aeruginosa, Staphylococcus aureus infection, as well as aspergillus, candida, Achromobacter, Acinetobacter, Serratia and Stenotrophomonas Maltophilia isolated from cough swabs/ sputum cultures were recorded. <b>Results:</b> Most lung function parameters showed significant progression with age (FRC, LCI, Scond, M1/M0, M2/M0, FEV1% predicted, FEF50% predicted). LCI was the most sensitive discriminator between the types of infection examined (p &lt; 0.0001). Pseudomonas aeruginosa infection, Staphylococcous, Achromobacter and stenotrophomonas maltophilia colonization were significantly associated with LCI. Cough and PeX were also significantly associated with LCI. A multiple regression was run to predict LCI deterioration from Pseudomonas aeruginosa-, Staphylococcus aureus –, other bacteria colonization and respiratory symptoms (cough, sputum). These variables predicted statistically significantly LCI, p &lt;0.001, R2 = 0.463. <b>Conclusion:</b> The LCI demonstrates progression of lung disease and corresponds to changes in respiratory symptoms and bacterial infections among children with CF. LCI may be a useful marker to track disease deterioration and may have a role in the routine clinical care of patients with CF.