Lessons learned from a randomized trial of airway secretion clearance techniques in cystic fibrosis.

RATIONALE

Airway secretion clearance therapies are a cornerstone of cystic fibrosis care, however longitudinal comparative studies are rare. Our objectives were to compare three therapies [postural drainage and percussion: (postural drainage), flutter device (FD), and high frequency chest wall oscillation: (vest)], by studying (1) change in pulmonary function; (2) time to need for intravenous (IV) antibiotics, (3) use of pulmonary therapies, (4) adherence to treatment, (5) treatment satisfaction, and (6) quality of life.

METHODS

Participants were randomly assigned to one of three therapies twice daily. Clinical outcomes were assessed quarterly over 3 years.

RESULTS

Enrollment goals were not met, and withdrawal rates were high, especially in postural drainage (51%) and FD (26%), compared to vest (9%), resulting in early termination. FEV(1) decline, time to need IV antibiotics, and other pulmonary therapies were not different. The annual FEF(25-75%) predicted rate of decline was greater in those using vest (P = 0.02). Adherence was not significantly different (P = 0.09). Overall treatment satisfaction was higher in vest and FD than in postural drainage (P < 0.05). Health-related quality of life was not different. The rate of FEV(1) decline was 1.23% predicted/year.

CONCLUSIONS

The study was ended early due to dropout and smaller than expected decline in FEV(1). Patients were more satisfied with vest and FD. The longitudinal decline in FEF(25-75%) was faster in vest; we found no other difference in lung function decline, taken together this warrants further study. The slow decline in FEV(1) illustrates the difficulty with FEV(1) decline as a clinical trial outcome.