Endocrinological and Nutritional Implications of Anorexia of Aging

Poor appetite—known as anorexia—is a common condition in aging and is associated with poor outcomes, including reduced survival and impaired quality of life. The anorexia of aging is mainly the result of several complex endocrinological, metabolic, and nutritional changes occurring with later age. The modulation of different peptides and hormones has been identified as an important determinant for the development of low appetite; in particular, an altered imbalance of plasma ghrelin, leptin, and cholecystokinin and increased inflammatory markers are implicated in its pathophysiology, and robust evidence of their involvement in anorexia of aging has been produced in the clinical setting. More recently, researchers identified that the gut microbiome composition significantly varies according to the appetite status. Other important clinical factors may worsen the symptoms of the anorexia in the elderly, in particular the potential concomitant presence of chronic catabolic comorbidities. Importantly, data indicate that anorexia is prevalent in frail older adults, negatively impacting body composition and specifically in altering muscle mass and function. For all these reasons, a prompt and early diagnosis of anorexia in the elderly is crucial to implement personalized metabolic and nutrition interventions to improve the outcomes and ameliorate quality of life