The demographic revolution and our common future.

The global population reached two billion people in 1927 and six billion in 1999. If the medium variant projection of the United Nations were to materialize, the Earth's population would reach nine billion in 2054. However, such a brave new world will be inhabited by a brave old humankind; in 2050, 16.4% of the world population and 27.6% of the European population are projected to be 65 years and above, and in 14 countries, including nine European ones, more than 10% of the total population will be 80 years or older. The United Nations also project a world-wide decline in the number of children and in total fertility, and by 2050, there will be more elderly than children in several parts of the world, particularly in Europe. It seems likely that many of our classical institutions, for instance healthcare -- unless reformed -- will cater increasingly for the needs of a population structure that no longer exists. The World Health Organization projects that by the year 2020, global health trends will be dominated by the ageing of the world population, the HIV/AIDS epidemic, tobacco-related mortality and declining child mortality. Furthermore, the leading causes of disease burden will be heart disease, depression and traffic accidents. How can we meet the giant challenges of the 21st century? In the view of the author, the most rational remedy must be a quantum leap in research in general and in medical research in particular.