Gender differences in proximal esophageal contractions

There are reports showing that gender has an influence on swallowing and on the contractions of the distal esophageal body.In this investigation we studied the effect of gender on proximal esophageal contraction.We studied 20 men (22-68 years old, median 39 years) and 44 women (18-61 years old, median 41 years) without symptoms and without gastrointestinal or respiratory diseases. We measured the time interval between the onset of pharyngeal contraction 1 cm proximal to the upper esophageal sphincter and the onset of the proximal esophageal contraction 5 cm from the pharyngeal recording. We also measured the amplitude, duration and area under the curve of the proximal esophageal contractions. The recording was performed by the manometric method with continuous perfusion. The contractions were recorded in duplicate after swallows of a 5 mL bolus of water.There were no differences between men and women in the interval between the onset of pharyngeal and of esophageal contractions or in the amplitude of esophageal contractions. The duration of contractions was longer in women (2.35 +/- 0.60 s) than in men (2.07 +/- 0.62 s) but the difference did not reach statistical significance (P = 0.087). The area under the curve of the esophageal contraction was higher in women (130.2 +/- 55.2 mm Hg x s) than in men (97.4 +/- 49.4 mm Hg x s, P = 0.026).We conclude that there is a difference between men and women in the proximal esophageal contractions in response to wet swallows, although this difference is of no clinical relevance.