The global challenge of ageing population – Part I: Definitions, epidemiology and physiological changes

Background & ObjectivesOver the past 50 years, epidemiological data from the World Health Organisation has demonstrated a trend towards population ageing throughout the world. While this is widely recognised in the developed world, the phenomenon has been largely overlooked in the developing world, despite the fact that the rate of ageing in developing countries far outstrips that of developed countries. This global trend towards an increasingly older society has significant implications for healthcare. This article aims to review the definitions of ageing, its epidemiological characteristics and physiological changes associated with ageing.MethodsA narrative review of the literature was undertaken using Medline, CINAHL and the Cochrane Database, supplemented by manual searches of the literature, and guided by the reference lists of relevant papers identified in the electronic search. No restriction was placed on the type of paper to be included in the study.ResultsThe initial electronic search of the three databases included 239 papers, of which 60 were found to be relevant and included in this review. These articles discussed the epidemiology and definition of ageing, the physiology of ageing and its impact on health and illness, and the implications for health services. The overall findings of the studies implicate the clear differences in the physiology of older people, which do create specific challenges for health service provision.ConclusionPopulation ageing is a significant global phenomenon, affecting both developed and developing regions of the world. More work is needed, particularly in the developing world, to better understand the impact of ageing on our population.