Objectives: The effects of gender on gastric emptying have not been fully elucidated. The aims of this study were to determine how gender affects gastric emptying and to see whether any of the observed differences in gastric emptying correlate with alterations in antral motility as measured by dynamic antral scintigraphy (DAS), cutaneous electrogastrography (EGG), and antroduodenal manometry (ADM).
Methods: Nine normal women [age 27.9 +/- 2.2 (mean +/- SEM) yr] in the first 10 days of the menstrual cycle and 13 normal men (age 27.5 +/- 1.7 yr) underwent simultaneous gastric emptying scintigraphy, DAS, EGG, and ADM. After an overnight fast and placement of an ADM catheter and EGG electrodes, a 60-min fasting recording was obtained, followed by ingestion of a 99m Tc-labeled solid meal. Measurements for all modalities were acquired every 10-15 min for 180 min.
Results: The gastric T1/2 was longer in women than in men [102 +/- 18 min vs. 71 +/- 4 (mean +/- SEM) min, p < 0.05]. A comparison of the gastric emptying pattern in women with that in men revealed no difference in proximal gastric emptying and lag phase, but in women the terminal slope of emptying was decreased compared with that in men (p < 0.05). The contractility measured in mid-antrum by DAS was significantly lower for women (p < 0.05). A decrease was also seen in the strength of contractions as measured by ADM.
Conclusions: These data demonstrate that gastric emptying of solid food in normal young, premenopausal women is slower than in age-matched men, even during the first 10 days of the menstrual cycle. The findings suggest that the delay is due primarily to altered distal gastric motor function. This hypothesis was corroborated by finding decreased antral contractility as recorded by both dynamic antral scintigraphy and ADM. This study demonstrates the need to use appropriate control values to evaluate symptomatic female patients.