Gut microbiota in relation to frailty and clinical outcomes

The gut microbiota is involved in several aspects of host health and disease, but its role is far from fully understood. This review aims to unveil the role of our microbial community in relation to frailty and clinical outcomes.Ageing, that is the continuous process of physiological changes that begin in early adulthood, is mainly driven by interactions between biotic and environmental factors, also involving the gut microbiota. Indeed, our gut microbial counterpart undergoes considerable compositional and functional changes across the lifespan, and ageing-related processes may be responsible for - and due to - its alterations during elderhood. In particular, a dysbiotic gut microbiota in the elderly population has been associated with the development and progression of several age-related disorders.Here, we first provide an overview of the lifespan trajectory of the gut microbiota in both health and disease. Then, we specifically focus on the relationship between gut microbiota and frailty syndrome, that is one of the major age-related burdens. Finally, examples of microbiome-based precision interventions, mainly dietary, prebiotic and probiotic ones, are discussed as tools to ameliorate the symptoms of frailty and its overlapping conditions (e.g. sarcopenia), with the ultimate goal of actually contributing to healthy ageing and hopefully promoting longevity.