Research from the World Population Program at the International Institute for Applied Systems Analysis in Austria presents a different way to measure aging. Since 1972, the IIASA has been conducting policy-oriented research into problems of a global nature, such as water, energy and world population. Its work is funded by member organizations in 21 nations worldwide, including the National Academy of Science in the United States.
In 2013, Sergei Scherbov and Warren Sanderson of IIASA co-wrote a report that examined the measuring of aging in individuals. Sanderson is also professor of economics and history at Stony Brook University in Long Island, NY.
WS: “In the study of aging, there’s been too much emphasis on age, which sounds kind of strange. The standard ways that people think about this, like measuring the proportion of the population 65 and above is absolutely wrong, because 65 year olds today are not like 65 year old were fifty years ago. They’re not like 65 year olds will be fifty years from now, because our life expectancy has been growing. People have been growing healthier. Cognitive decline has been put off to older and older ages. And older people in the future are going to be more educated than older people who are around now. So we’re saying that when you want to study aging, we have to look at the characteristics and the functioning of people, not just how many birthdays they’ve had.”
KI: How would you propose to track aging more effectively?
WS: “The simple way to do this, instead of counting how many birthdays they’ve had and say they’re going to be old at 65, count how many birthdays people expect to have in the future. That’s their life expectancy. And when we adjust aging measures for life expectancy, we get a whole different picture of what aging is going to be like in individual countries and in the United States. An aging problem is going to be much, much less than people currently perceive it.”
KI: How is life expectancy determined?
WS: “It’s usually determined on a population basis. We have wonderful data on life expectancies because we have death certificates. We know on average how long people at various ages are likely to live. Demographers have studied this a long time and our data on this are very good. In developed countries, life expectancy at age 65 has been increasing between one and two years per decade for a long time, and this is likely to continue.”
KI: How would age be measured?
“If you want to know how fast various groups in the population have aged, so if I want to ask, have more educated people aged faster than less educated people, I can’t use age, because 65-year olds are 65 years old if they’re more educated or less educated. So you need to find some other variable which summarizes very well the characteristics of people at various ages. And we’ve found, rather amazingly, that hand grip strength does that. Hand grip strength is very easily measured, and there are a number of surveys now that actually measure this. And we’ve found that by measuring hand grip strength, 69-year old white women, for example, who are more educated, are the equivalent of 65-year old women with less education. So those women with more education have aged more slowly.”
KI: How can this information be applied?
WS: It’s measured by hand grip strength, which we show in our article as a very good predictor of future mortality and morbidity. Actually a measure of future cognitive decline as well. We’re recommending to doctors, your primary care doctors, that they all get one of these ahdn grip measuring devices, which are $50 or something like that. It takes two seconds, could be done by somebody who takes your blood pressure. If your primary care doctor had measurements on your hand grip strength every six months or every year when you came in, it would turn out to give them a much better reading in what’s going on with you in general than many other things that they do.”
KI: How did you come to these conclusions?
WS: “We reviewed a lot of literature on this. One study had a million Swedish young men. Another study had Taiwanese men and women in nursing homes. We have surveys from all over the world, all of which show the same thing, and they go from young people to old people to people in the community to people in nursing homes. We have evidence about how fast you recover from operations in the hospital. All of them suggest the same thing, that hand grip is an amazingly good measure of what’s gonna happen to you. Once we reviewed all these studies and determined that we could use this as a good summary measure, then we used it to look at the speed of aging.”
You can read more about the study on Warren Sanderson’s page on theconversation.com.
Katya Ivanov, WUWF News