The role of ghrelin in the energy homeostasis of elderly people:: A population-based study

Objective: Ghrelin is a hormone secreted mainly in the stomach which stimulates appetite and food intake. Endocrine factors are among the causes of anorexia in elderly people. The main objective of the present study was to examine the effect of age on ghrelin levels in non-institutionalized elderly people. Design and setting: Observational, cross-sectional, population-based study. Participants: A random sample of men aged 70 yr or older was taken from the municipal census. Measurements: All participants underwent a physical examination which measured weight and height, grip strength, functional capacity (according to the Barthel Index) and nutritional status (according to the short form of the Mini Nutritional Assessment). Blood was taken for basic biochemical analysis, determination of somatotropic, corticotropic, and gonadotropic hormones, and for measurement of ghrelin and cholecystokinin. Results: 152 men with a mean (SD) age of 76.7 (5.4) yr were recruited. Mean ghrelin levels were 1143 (401) pg/ml. A weak negative correlation was found between ghrelin levels and age (r=-0.16, p=0.057). Multiple linear regression analysis showed a significant and independent effect of age (beta=-12.1, p=0.049), body mass index (BMI) (beta=-22.0, p=0.021), and creatinine levels (beta=407.7, p=0.002) on ghrelin. No correlations with age and BMI were found for cholecystokinin. Conclusions: There is a slight decrease in ghrelin levels with age in older men aged 70 yr or more, although the clinical relevance of this finding remains unclear.