O032 Gastrointestinal and satiety responses to oral feeding in participants with obesity compared with those of healthy weight: an MRI study

Abstract

Abstract Introduction Satiety is regulated by behavioural and physiological mechanisms. This study aimed to investigate the effects of food ingestion on subjective satiety, gastric emptying, mesenteric blood flow, and blood glucose concentration. Methods Twenty healthy males (10 Lean:10 Obese) were recruited to the study. Gastric content volume (GCV) and superior mesenteric blood flow (SMABF) were measured by magnetic resonance imaging (MRI) (Philips 3T Ingenia and dStream Anterior Coil at baseline) during fasting and immediately after a standard meal (2.5MJ, 78g Carbohydrate, 24g Protein, 21g Fat) and then every 30-minutes for four hours. Gastric emptying rate (GER) was derived from GCV. Blood glucose (BG) and combined satiety scores (CSS; 0–100 mm visual analogue scale) were measured. Data were presented as mean (SD). Results Participants in the lean (age: 38(14) y, BMI: 24(2) kg/m2) and obese (age: 38(13) y, BMI: 34(3) kg/m2) groups showed no statistically significant differences in fasting CSS [39.1(22.6) vs. 30.9(13.5) mm], GCV [59(32.6) vs. 58(29.6) ml], SMABF [7.7(2.5) vs. 6.5(2.6) ml/s], and BG [4.5(0.8) vs. 4.2(0.5) mmol/l]. In response to eating, no differences were seen in CSS, GCV, BF, and BG between the groups. Postprandial CSS correlated positively with GCV (R2=0.42, P<0.001 vs. R2=0.30, P<0.001). GER did not differ between the groups (1.7 vs. 1.8 ml/min). Participants with obesity reported lower satiety scores immediately after eating [85(22.6) vs. 67(22.7) mm] and across the 4 hours (P<0.05). Conclusion Participants with obesity reported lower postprandial subjective satiety. However, this did not appear to be related to gastrointestinal function.