Delayed postprandial gastric emptying and impaired gallbladder contraction together with elevated cholecystokinin and peptide YY serum levels sustain satiety and inhibit hunger in healthy elderly persons

Abstract

Background. Altered gastric and cholecystic motility are risk factors for malnutrition in elderly persons, mainly through impaired satiety-appetite rhythm. Contrasting data have been published about this topic. The aim of this study was to evaluate, in healthy elderly participant, postprandial gastric and cholecystic emptying in relation to serum CCK (cholecystokinin) and PYY (peptide YY), as well as satiety and hunger sensations. Methods. We studied 10 community-dwelling elderly persons, (77 ± 3 years old) and 9 younger adult persons (32 ± 8 years old). Using ultrasonography, we measured gastric antrum area and cholecystic volume in fasting condition and after an 800-kcal mixed meal. Time for gastric and cholecystic emptying, and percentage of cholecystic emptying were calculated. Satiety and hunger were evaluated every 30 minutes using visual analogue scales. CCK and PYY serum levels were assayed 30 minutes before and at times 0, 30, 60, 120, and 240 minutes after the meal. Results. Elderly participants showed a longer gastric emptying time compared to younger participants (448 ± 104 vs 306 ± 57 minutes, p < .002). Postprandial cholecystic emptying was significantly reduced in the older group (maximum contraction, 69% vs 84%; p < .05). After the meal, CCK and PYY levels showed higher, persistent elevation in elderly participants. In this group, postprandial satiety lasted significantly longer than in younger participants, and hunger was suppressed throughout the postprandial period. Antral area directly correlated with satiety and inversely with hunger. Gallbladder volume inversely correlated to satiety. Conclusions. This study showed, in a group of healthy elderly people, delayed gastric emptying associated to reduced cholecystic contractility together with higher CCK and PYY serum levels. These modifications facilitated long-lasting satiety and hunger suppression after a meal. This condition may lead to caloric restriction and finally to malnutrition at older ages.