FREQUENCY OF GASTROESOPHAGEAL REFLUX EVENTS INDUCED BY PHARYNGEAL WATER STIMULATION IN YOUNG AND ELDERLY SUBJECTS

Earlier studies have shown that isolated complete lower esophageal sph incter (LES) relaxation occurs as a result of pharyngeal water stimula tion. Association of these relaxations with gastroesophageal reflux ha s not been studied systematically. Our aim was to determine this assoc iation in young and elderly subjects during precibal and postprandial periods. We studied 8 young subjects and 10 elderly subjects for 1 h b efore and 2 h after a 1,000-cal meal. In both groups, during the preci bal period, negligible LES relaxation induced by pharyngeal water stim ulation resulted in gastroesophageal reflux. In the postprandial perio d, gastroesophageal reflux events occurred after 16% of pharyngeal wat er injections in young subjects and after 44% in elderly subjects (P < 0.05). Intraabdominal length of the LES in elderly subjects was signi ficantly shorter compared with younger subjects (P < 0.05). We conclud e that gastroesophageal reflux events induced by pharyngeal water stim ulation in the postprandial period are significantly increased compare d with those of the precibal period and are significantly more prevale nt in the elderly compared with the young. These differences seem to b e associated with a significantly shorter intra-abdominal segment of t he LES in the elderly.