We are rapidly approaching a demographic transition of momentous global importance.
For the first time in human history, the number of people over the age of 65, as a percentage of the global population, will surpass the number of children under the age of five. At the same time, this demographic “X” is being matched by an unprecedented shift in the global burden of disease, with a sharp decrease in infectious diseases and a startling rise in the level and duration of chronic afflictions such as diabetes, cancer, heart disease, and Alzheimer’s.
While individual longevity is a cause for celebration, governments now look to contain or curtail potentially astronomical expenditures on aging-related social and health care. “Healthy life expectancy” will be the new metric of success for health systems desperate to delay the human and financial cost of disability in their populations.
This unprecedented transition demands nothing less than a revolutionary new “algebra” to help us “solve for x” and redefine the equation for global health. In order to cash in our “longevity dividend,” we must develop dramatically more innovative policies, technologies, products, and services.
As Figure 1 shows, within 5 years, the number of people over the age of 65 as a percentage of the global population will surpass the number of children under the age of five. From that point of intersection, the trend lines will diverge dramatically to form an almost perfect “X” that spans the century from 1950 to 2050.1 The World Health Organization (WHO) estimates that there will be two billion people over the age of 60 by the year 2050.2
Moreover, the blue line in this demographic X marks a change that is truly global. Populations are aging fastest in low- and middle-income countries. While Europe and Japan’s “aging” has long been tracked with interest, the world is just waking up to the implications of rapid aging in countries such as Brazil and Thailand, and that China’s median age will be 49 by 2050.
Simultaneously, the green trend line marks an unprecedented decline in global fertility rates. This shift, and its implications, is now being covered in global media sources. The Economist noted recently that the city of Shanghai reported fertility of just 0.6 in 2010 — probably the lowest level of anywhere in the world. As Figure 2 shows, Taiwan provides a startling example of declining fertility, dropping from seven births per woman in 1950 to below one in 2010.
Lastly, the velocity of this transition is unprecedented. One of the classic measurements for the speed of population aging is to measure the number of years required by a society to move from 7 percent to 14 percent over the age of 65. Whereas most European societies took a century to make this journey, Figure 3 shows us that Asian societies now reach that destination in less than a generation.
What can we begin to do now?
These unprecedented circumstances demand nothing less than a revolutionary new “algebra” to help us solve for X and redefine the equation for global health.
Figure 4 shows the world mortality rate by age group. We could argue for many markers of aging, but mortality does mark the most definitive point of success or failure. In light of our mission “to sustain health through the integration of molecular and behavioral metrics to improve outcomes and lower costs” is there a particular opportunity to target a global age cohort approaching 60 years of age, a cohort facing imminent aging and retirement challenges, yet still capable of behavioral changes that might pull the mortality curve down?