McRae, Alison

Abstract Satiation is the physiologic process that regulates meal size and termination, and it is quantified by the calories consumed to reach satiation. Given its role in energy intake, changes in satiation contribute to obesity's pathogenesis. Our study employed a protocolized approach to study the components of food intake regulation including a standardized breakfast, a gastric emptying study, appetite sensation testing, and a satiation measurement by an ad libitummeal test. These studies revealed that satiation is highly variable among individuals, and while baseline characteristics, anthropometrics, body composition and hormones, contribute to this variability, these factors do not fully account for it. To address this gap, we explored the role of a germline polygenic risk score, which demonstrated a robust association with satiation. Furthermore, we developed a machine-learning-assisted gene risk score to predict satiation and leveraged this prediction to anticipate responses to anti-obesity medications. Our findings underscore the significance of satiation, its inherent variability, and the potential of a genetic risk score to forecast it, ultimately allowing us to predict responses to different anti-obesity interventions.

Abstract Background Spontaneous hyperinflation is reported to the Food and Drug Administration as a complication of intragastric balloons. It is postulated that orogastric contamination of the intragastric balloon may cause this phenomenon. We sought to investigate the effects of intentional balloon contamination with gastric contents on intragastric balloon diameter and contents, whether methylene blue plays a role in preventing spontaneous hyperinflation, and review the available literature on spontaneous hyperinflation. Methods Four pairs of balloons with different combinations of sterile saline, contaminants, and methylene blue were incubated in a 37° Celsius water bath for 6 months to simulate physiological conditions with serial measurements of balloon diameter. Our findings were compared against a systematic review across multiple databases to summarize the available literature. Results Balloon mean diameter decreased from 33.5 cm ± 0.53 cm to 28.5 cm ± 0.46 cm (p < 0.0001). No significant differences were seen with the methylene blue group. Only 11 cases were found reported in the literature. Conclusions Despite contaminating intragastric balloons with gastric aspirates, hyperinflation did not occur, and other factors may be in play to account for this phenomenon, when observed. Rates of hyperinflation remain under-reported in the literature. Further controlled experiments are needed.