Factors influencing treatment response of pulmonary exacerbation in children with cystic fibrosis.

Abstract

Pulmonary exacerbations in cystic fibrosis (CF) significantly impact morbidity and mortality. This study aimed to assess treatment response rates and identify contributing factors towards treatment response. In this single-center, retrospective, longitudinal study spanning four years, we analyzed all pulmonary exacerbation admissions. We compared lung function at baseline, admission, end of treatment, and 6-week follow-up. Treatment response was defined as ≥95% recovery of baseline FEV<inf>1</inf>%. There were 78 children who required a total of 184 admissions. The mean duration of treatment was 14.9±2.9 days. FEV<inf>1</inf>% returned to 95% of baseline in 59% following treatment. The magnitude of the decline in lung function on admission in children who did not respond to treatment was 21.7±15.2% while the decline in children who responded to treatment was 8.3±9.4%, P<0.001. Children who experienced a decline in FEV<inf>1</inf>% greater than 40% exhibited an 80% reduced likelihood of returning to their baseline values (OR -0.8, 95% CI -0.988; -0.612). Similarly, those with FEV<inf>1</inf>% reductions in the ranges of 30-39% (OR -0.63, 95% CI -0.821; -0.439), 20-29% (OR -0.52, 95% CI -0.657; -0.383), and 10-19% (OR -0.239, 95% CI -0.33; -0.148) showed progressively lower odds of returning to baseline. Fourty-eight children required readmission within 7.7±5.4 months, children who responded to treatment had a longer time taken to readmission (8.9±6.4 months) versus children who did not respond to treatment (6.4±3.5 months), (OR: -0.20, 95% CI -0.355; -0.048). A greater decline in lung function on admission and readmission within 6 months of the initial admission predicts non-response to treatment. This highlights the importance of re-evaluating follow-up strategies following discharge.