Influence of dentures on residual inhaled corticosteroids in the mouths of elderly asthma patients.

Background: The influence of dentures on residual inhaled corticosteroids (ICSs) in the mouths of elderly asthmatic patients and the appropriate time for gargling after inhaling ICSs are unclear.

Methods: Twenty elderly patients in whom moderate persistent asthma was stably controlled using fluticasone propionate Diskus (FP, n = 10) or hydrofluoroalkane-beclomethasone dipropionate (HFA-BDP, n = 10) for more than 3 months and who wore dentures daily were switched to the other type of ICS for 4 weeks in a crossover manner. The residual amount of each ICS in their mouths after inhalation was measured along with determination of peak inspiratory flow (PIF) and pharyngeal culture for detecting Candida albicans.

Results: The total amounts of residual ICSs in gargling fluids (μg) with HFA-BDP were significantly greater than those with FP (15.6 ± 14.6 vs. 11.5 ± 13.8, p = 0.028). The residual amounts of HFA-BDP were significantly greater in the patients with complete dentures than in those with partial dentures. The residual amounts of FP were significantly correlated with the PIF values in the FP treatment (p = 0.013) but not in the HFA-BDP treatment (p = 0.202). No residual ICSs remained after the third gargling in either treatment. The occurrence of candidiasis during the HFA-BDP period was significantly higher than that during the FP treatment (p = 0.046).

Conclusion: The dentures of elderly asthmatics affect the oral residues of ICSs and occurrence of candidiasis in HFA-BDP treatment; meanwhile, the PIF values affected these factors in FP treatment. Three times gargling after inhaling ICSs is required.