Effects of aging on sensitivity of the pharyngeal and supraglottic areas.

As one ages, sensory discrimination in the oral cavity progressively diminishes, and dysphagia and aspiration are more likely to occur. Whether similar age-related laryngopharyngeal (LP) sensory abnormalities exist and contribute to dysphagia and aspiration is unknown. The purpose of this study was to determine if sensory discrimination in the area of the laryngopharynx innervated by the superior laryngeal nerve diminishes with increasing age. By applying a previously described device and technique that utilized endoscopically delivered air pulse stimulation of the anterior wall of the pyriform sinus, sensory discrimination can be reliably determined. LP sensory discrimination testing was performed in 80 healthy adults 23-87 years of age, with a mean age of 47 +/- 20 years. There were 60 men and 20 women. The test subjects were divided into 3 age groups, 20-40, 41-60, and > or =61. For the entire population studied, average LP sensory discrimination thresholds were 2.60 +/- 0.56 mm Hg air pulse pressure (APP). In general, there was a progressive increase in sensory discrimination threshold with each decade of life. A correlation analysis revealed that there were significant increases in pressure thresholds with advancing age (r = 0.62, P <0.0001). For subjects 20-40 years, average threshold was 2.06 +/- 0.20 mm Hg APP, for the 41-60 age group, 2.45 +/- 0.34 mm Hg APP, and for subjects > or =61, 2.97 +/- 0.78 mm Hg APP. Thresholds for the > or =61 group were significantly different from those for the 20-40 and the 41-60 groups (P <0.05). Progressive diminution in LP sensitivity with increasing age might be a contributing factor in the development of dysphagia and aspiration in the elderly.