The coming acceleration of global population ageing

Abstract

The future paths of population ageing result from specific combinations of declining fertility and increasing life expectancies in different parts of the world. Here we measure the speed of population ageing by using conventional measures and new ones that take changes in longevity into account for the world as a whole and for 13 major regions. We report on future levels of indicators of ageing and the speed at which they change. We show how these depend on whether changes in life expectancy are taken into account. We also show that the speed of ageing is likely to increase over the coming decades and to decelerate in most regions by mid-century. All our measures indicate a continuous ageing of the world's population throughout the century. The median age of the world's population increases from 26.6 years in 2000 to 37.3 years in 2050 and then to 45.6 years in 2100, when it is not adjusted for longevity increase. When increases in life expectancy are taken into account, the adjusted median age rises from 26.6 in 2000 to 31.1 in 2050 and only to 32.9 in 2100, slightly less than what it was in the China region in 2005. There are large differences in the regional patterns of ageing. In North America, the median age adjusted for life expectancy change falls throughout almost the entire century, whereas the conventional median age increases significantly. Our assessment of trends in ageing is based on new probabilistic population forecasts. The probability that growth in the world's population will end during this century is 88%, somewhat higher than previously assessed. After mid-century, lower rates of population growth are likely to coincide with slower rates of ageing.

Human Capital and Sustainability

“…Most European countries are either slightly or below the replacement level. Stochastic projections of world population published by the IIASA show a 80-85% chance that the world population will peak and start to decline before the end of the 21st century [116]. Other studies project that if global fertility rates were to fall to the level already prevalent in Europe for the past decade, then world population could decline to the range of 3.5 to 4.4 billion in 2200 and 1.1 to 1.7 billion in 2300 [117].…”

Problems, challenges and promises: perspectives on precision medicine

“…In addition, models are being generated to account for pharmacokinetics and pharmacodynamics to analyse drug action, and even human-population level pharmacogenomics models of disease risk [10,39,40]. A direct challenge facing precision medicine is not only the generation of models at these disparate levels but the incorporation of models accounting for different levels of organisation into holistic multi-scale models [10] While not all treatment decisions require holistic multi-scale models, the aging demographic of the global population [45,46] is driving increased occurrence of comorbidities. Such comorbidities result in patients being prescribed multi-drug regimens (drug cocktails), often with prescriptions coming from different healthcare specialists.…”

Learning to live long

“…Vor allem in europa und Japan wird sich die Alterung besonders beschleunigen (Lutz et al 2008). Schon heute ist Deutschland -gemessen am Anteil der über 60-Jährigen an der Gesamtbevölkerung - nach Japan und Italien das drittälteste Land der welt.…”