Postprandial cholecystokinin secretion in elderly with protein-energy undernutrition.

Objective Malnutrition is currently observed in aged people, and cholecystokinin is an important peripheral satiety signal. The aim of this study was to examine the effect of aging and protein-energy malnutrition on postprandial cholecystokinin (CCK) release. Design Non-randomized, cross-sectional comparison by age group. Setting Gastroenterology section of a teaching hospital. Participants Twenty-one human volunteers divided into three groups: young healthy subjects (Group 1: mean 29 years, n = 7), aged healthy subjects (Group 2, mean 80 years, n = 7), and aged subjects with an important degree of malnutrition (Group 3, mean 84.6 years, n = 7). Intervention Each subject ingested a standardized liquid meal after an overnight fast. Main Outcome Measures Plasma cholecystokinin was measured using a sensitive bioassay before and after the ingestion of the liquid meal. Results Basal cholecystokinin levels were similar (0.9 to 1 pm equivalent CCK-8) in the three groups. Postprandial levels were significantly increased over basal (P < 0.05). The maximal cholecystokinin value was lower in Group 1 (3.5 ± 0.8 pm equivalent CCK-8) and Group 2 (3.3 ± 0.77 pm equivalent CCK-8) than in Group 3 (8.3 ± 2 pm equivalent CCK-8) (P < 0.05). Integrated plasma cholecystokinin was also similar in Group 1 (171 ± 38 pm · 60 min), (P < 0.05). Conclusion The increase of postprandial maximal levels of cholecystokinin is more related to malnutrition than to aging.