Alexandre Kalache, MD, PhD,
Chief, Ageing and Life Course (ALC),
World Health Organization,
Geneva, Switzerland.
Ingrid Keller, MSc, MPH
Associate Professional Officer, ALC,
World Health Organization,
Geneva, Switzerland.
Introduction
Within the next few decades, one of the defining features of the world population will be the rapid increase in the absolute and relative numbers of older people in both developing and developed countries. We are currently at the threshold of global aging. Worldwide, the total number of older people--defined as those over 60 years of age--is expected to increase from 605 million in 2000, to 1.2 billion by the year 2025.1 Currently, approximately 60% of older persons live in the developing world, a number that is expected to increase to 75% (840 million) by the year 2025. Figure 1 shows the proportional increase of older persons among the total population for some developing countries as compared to the Canadian population.
In the year 2000, in a number of developed countries, there were, for the first time, more people aged 60 and older than there were children under the age of 14.1 Population aging could be compared with a silent revolution that will impact on all aspects of society. It is imperative that we are adequately prepared for it: the opportunities and the challenges are multiple.
