Background: We hypothesized that adding 5 days of prednisone to standard therapy for acute pulmonary exacerbations in patients with cystic fibrosis (CF) would result in a more rapid and greater increase in lung function.
Methods: CF patients with an acute pulmonary exacerbation were randomized to receive oral placebo or prednisone, 2 mg/kg/d up to 60 mg, on days 1 to 5 in addition to standard therapy. Study evaluations on days 1 to 6, 14, and 42 included spirometry, glucose measurements, sputum analysis, and symptom scores.
Results: Twelve subjects were randomized to each arm. The slope of FEV1 between day 1 and day 6 did not differ between evaluable subjects in the prednisone vs placebo groups (52 mL/d vs 51 mL/d, respectively). Mean increase in FEV1 percentage of predicted did not differ significantly between prednisone vs placebo groups (day 6 [mean ± SD], 12.2 ± 5.2% vs 8.1 ± 10.5%; day 14, 14.7 ± 8.8% vs 10.2 ± 11.2%, respectively). Sputum inflammatory markers and symptom scores decreased between day 1 and day 14, but mean values did not differ between groups. Glucosuria occurred in six prednisone subjects, two of whom had hyperglycemia develop.
Conclusions: In this pilot study, addition of oral corticosteroids to standard CF pulmonary exacerbation therapy did not result in a statistically significant effect on lung function or sputum markers of inflammation. Based on a trend toward improvement in pulmonary function with prednisone therapy, we obtained information for power calculations for a definitive study: 250 randomized subjects are required to detect a four-percentage-point treatment effect in FEV1 percentage of predicted at day 14 to discriminate between null and alternative hypotheses.