The causes of age-related hoarseness include 1) a decreased amount of mucus covering the vocal cord surface; 2) a decreased content of hyaluronic acid in the superficial layer of the vocal cord lamina propria ; and 3)） age-related atrophy of the vocal cord. Patients with presbyphonia resulting from the second or third causes listed above often show evidence of vocal cord atrophy, such as imperfect closure of the glottis and reduced duration of glottal closure. Some of the middle-aged and older patients with little evidence of vocal cord atrophy have relevant endoscopic findings and/or subjective symptoms, such as sputum sticking sensation during speech and dry mouth. Saliva keeps the vocal cord mucosa moist and serves as a lubricant during speech. Only a limited number of studies have examined the relationship between reduced moisture content of the vocal cord mucosa associated with hyposalivation and the development of presbyphonia. The objective of this study was to evaluate the effectiveness of sialagogue pilocarpine hydrochloride in improving vocal function in patients with vocal disorders considered to be caused by reduced moisture content of the vocal cord mucosa due to hyposalivation. This study included 20 patients aged 60 years and up who were complaining of hoarseness suspected to be the result of reduced secretion of laryngeal mucus and who displayed no apparent space-occupying lesion or vocal cord atrophy. Pilocarpine hydrochloride administered via tablets 1-3 times daily for 4 weeks resulted in increased saliva secretion as well as significant improvement in VHI and acoustic parameters. The results demonstrate the efficacy of pilocarpine hydrochloride for promoting saliva secretion in the treatment of presbyphonia.
