Introduction

Globally, the population is ageing – virtually every country in the world is experiencing growth in both the size and proportion of older people in their population (United Nations, 2019). The United Nations (2019) estimates that, by 2050, one in six people in the world will be aged over 65, up from one in 11 in 2019. The proportion of adult life spent beyond the age of 65 stands at a quarter or more at most developed countries (United Nations, 2019). The number of people aged 60 and over now outnumbers children younger than five years (World Health Organisation, 2019).