Dry mouth as a novel indicator of hoarseness caused by inhalation therapy

To investigate the influence of dry mouth on the incidence and severity of inhalation therapy-induced hoarseness.

The volume of saliva secreted without stimulation was measured in patients with asthma or chronic obstructive pulmonary disease (COPD) who also answered a questionnaire on subjective ratings for hoarseness. The relationship between salivary secretion and hoarseness was analyzed by the Pearson correlation and multiple linear regression. The prediction accuracy of salivary secretion for the grade of hoarseness was evaluated using a receiver-operating characteristic (ROC) analysis.

A total of 232 patients participated in this study. The subjective rating score of hoarseness was negatively correlated with the volume of saliva secreted (r = -0.273, p < 0.001). A stepwise multiple linear regression analysis revealed that salivary secretion (p < 0.001) and the dose of fluticasone administered (p < 0.05) were significant variables for predicting hoarseness. The ROC analysis for predicting severe hoarseness by salivary secretion showed significant prediction accuracy (AUC = 0.690, 95% CI: 0.614-0.766, p < 0.001) and was higher in patients administered fluticasone (AUC = 0.732, 95% CI: 0.644-0.821, p < 0.001).

Hyposalivation is a significant prediction factor of hoarseness induced by inhaled corticosteroids (ICS). The prediction accuracy was higher in patients administered fluticasone than in those administered another inhalation drug. Although the pharmaceutical efficacy of fluticasone is high, patients with hyposalivation should be prescribed other inhalation drugs.