Inhaled beclomethasone dipropionate improves acoustic measures of voice in patients with asthma

Inhaled corticosteroids have the potential to produce upper-airway side effects such as hoarseness. As new compounds and delivery devices are developed and compared, it is difficult to quantify their adverse upper-airway effects.

We undertook the following study to test the ability of an acoustic analysis technique to quantify changes in vocal function in steroid-naive patients with asthma who receive inhaled beclomethasone dipropionate (BDP), 1,000 microg/d for 4 months.

Patients self-administered one of four regimens of inhaled BDP. Group 1 patients received one 250-microg puff qid via metered-dose inhaler (MDI); group 2 patients received one 250-microg puff qid via MDI with a holding chamber; group 3 patients received two 250-microg puffs bid via MDI; and group 4 patients received two 250-microg puffs bid via MDI with a holding chamber. A smaller cohort of nonsmoking asthmatic patients was managed without steroid intervention for 4 months. At baseline and again at 8 weeks and 16 weeks after the initiation of BDP treatment, patients underwent spirometry and methacholine challenge. At baseline and again at 2, 4, 8, 12, and 16 weeks, patients underwent voice recording for analysis of voice parameters. The recorded vowels were low-pass filtered (10 KHz), digitized (22 KHz), and analyzed by software to obtain two acoustic measures: (1) jitter, the cycle-to-cycle variation in the time period of the voice signal; and (2) shimmer, the cycle-to-cycle variation in voice signal amplitude.

We recruited 77 patients for randomization to inhaled steroid therapy and 10 patients who continued to receive only occasional inhaled bronchodilator therapy. In all active treatment groups, FEV(1), FVC, and provocative concentration of methacholine causing a 20% fall in FEV(1) improved significantly after BDP treatment. Mean jitter scores, a measurement of variation in voice pitch, were not significantly influenced by BDP treatment. However, mean shimmer scores, a reflection of perturbation in vocal amplitude, fell significantly (p < 0.05) in the active treatment groups. These reductions in shimmer scores were not significantly different in the active treatment groups. Shimmer scores in the bronchodilator-treated group were unchanged during the 16 weeks of follow-up.

Our data show that a simple and noninvasive acoustic analysis of voice is sensitive to subclinical changes associated with inhaled corticosteroid therapy. We have shown that 1,000 microg/d of inhaled BDP actually improves specific acoustic measures of voice in patients with inadequately controlled asthma. These improvements were uninfluenced by dosing schedule and whether a spacing chamber was used.