Gastric emptying time of fluids and solids in healthy subjects determined by 13C breath tests:: influence of age, sex and body mass index

Background and Aim: Disturbance of gastric emptying leads to a variety of symptoms. Furthermore, gastric motility disorders might play a role in the pathophysiology of functional dyspepsia. In previous studies C-13 breath tests were validated as non-invasive tools in the measurement of gastric emptying time. So far, reliable reference values of healthy subjects are missing and the impact of constitutional traits (age, sex, body mass index [BMI]) needs to be clarified. Methods: A study was conducted in 90 healthy individuals (45 men, 45 women) that assessed the correlation of parameters of gastric emptying (half gastric emptying time [T-1/2] and time of fastest gastric emptying [T-lag]) with age, sex and BMI for fluid and solid test meals by C-13 breath tests. 100 mg of sodium acetate or sodium octanoate, respectively, were used as tracers. Breath probes were analyzed by non-dispersive infrared spectroscopy. Results: The mean +/- SD of half gastric emptying time (T-1/2) of a fluid test meal was determined to be 80.5 +/- 22.1 min and for Tlag to be 40.3 +/- 10.2 min. However, the T-1/2 and Tlag of solid meals did not fit to normal distribution and thus median and percentiles were determined. The median time of T-1/2 for solids was 127 min (25-75% percentiles: 112.0-168.3 min) and 81.5 min for T-lag (25-75% percentiles: 65.5-102.0 min). No significant correlation was found between gastric emptying and age, sex or BMI. Conclusion: This is the first study to examine gastric emptying in an adequate number of healthy subjects by C-13 breath tests. No significant correlation was found with age, sex and BMI. Although there is considerable standard deviation in gastric emptying time, these results may nevertheless serve as reference values for further studies.