As Baby Boomers and other population segments age across the world, demographers are studying how the transition will influence global economy.
Chronological age is not an accurate indicator of potential social and economic burden as many elders are “functionally” younger than their stated age, a new study suggests.
Instead, experts say cognitive function, rather than age distribution, is a better indicator of the impact of aging on an economy.
The study is published in the Proceedings of the National Academy of Sciences.
Investigators found one standardized indicator of cognitive ability – memory recall – is better in countries where education, nutrition, and health standards are generally higher.
Aging populations — such as the Baby Boomer cohort in the U.S. — are of concern to many countries as it is often assumed that aging necessarily implies a greater cost to society in terms of aged care, age related disease, and reduced capacity to contribute to society.
However, research suggests that the effects of chronological aging are uneven across nations and that in some countries, particularly more affluent ones that are able to invest in early and sustained education and health programs, cognitive function and thus the ability to live healthy, productive lives is maintained longer.
“Demographic indicators of the economic impact of an aging population typically rely on measures based on populations’ age-distribution, expressed as the Old Age Dependency Ratio (OADR). While this is a helpful measurement, it does not include information on individual characteristics, other than age,” said lead author Vegard Skirbekk, Ph.D., from the International Institute for Applied Systems Analysis (IIASA).
“We believe cognitive function can provide a new and comparable measure of how a region or a nation’s population may age. Such information can inform early intervention in the education and health systems to try and improve cognitive performance, ultimately reducing the burden of aging.”
Skirbekk is a demographic researcher at IASA, an independent international research group that examines problems like population aging or climate change that are too large or complex for one country or academic field.
“For example, in northern Europe or the United States where there is a relatively large population over the age of 65, we found that cognitive function is higher for this age group than for the same age group in Mexico, India and China. Overall, even though Europe and the US may be chronologically older they are ‘functionally’ younger,” Skirbekk said.
Cognitive ability levels are also good indicators of individual productivity which has direct relevance to economic and business activities within a country.
The authors suggest that the difference in cognitive function may be explained by the fact that seniors in some regions of the world experience better conditions during their childhood and adult life; including nutrition, duration and quality of schooling, exposure to disease, and physical and social activity.
The study involved surveys of people aged over 50 years from a range of countries including the U.S., Mexico, India, Japan, and across Europe, from both urban and rural areas. The surveys measured, among other parameters, short-term memory, or the ability to immediately recall words read out to the participants. Immediate recall has been shown to influence decision-making ability and the risk of dementia.
According to the authors, because aspects of cognitive functioning at older ages can now, for the first time, be more readily compared, such a measurement may also serve as a benchmark for countries to assess the burden of aging across nations.