If I am 58 years old, it has been 58 years, or 21,170 days (at least) since I was born. This is my chronological age. But what if this way of conceiving age was becoming obsolete? From the deep reflections on aging, life expectancy and longevity, new perspectives have appeared.
Biological age, for example, is, as the Ageingnomics Research Center explains, “the indicator of the real state of the body, which depends on the peculiar, unique and unrepeatable vital process that each person experiences. Unlike chronological age - which is only based on the time that has passed since birth -, biological age is the age of the organism. That is to say, despite my 58 years of chronological age, I may be 48 years biologically old or I may be 70 biological years old, with a body affected by bad habits or pathologies.
A third interesting concept that is being talked about more and more is the so-called prospective age: the years we have left to live. “Prospective age refers to a paradigm shift: age is no longer only defined by the number of years lived, but by what is expected to be achieved in the future. This is linked to various factors that can influence longevity and quality of life,” Francisco Tarazona, geriatrician and coordinator of the medical area of the Ribera University Hospital (Alcira) and clinical member of the Society's Board of Directors, explains to La Vanguardia. Spanish of Geriatrics and Gerontology.
This idea is also influenced by each individual's perception of their own life. “Prospective age focuses on various biological factors, but also the person's attitude and perspective on their own life and their future, rather than on their chronological age,” Tarazona points out.
“Chronological age and prospective age are different lenses to see the same reality and understand the implications of aging,” explains Simon Lloyd, doctor in environmental sciences and researcher at ISGlobal, a center promoted by the “la Caixa” Foundation. Simon Lloyd and other researchers have just published a study in the journal Environmental Research on aging and mortality associated with temperatures in Spain over the last 40 years. In it they explain that “an alternative conceptualization of aging, pioneered in demography and proposed by Warren Sanderson and Sergei Scherbov, suggests that using chronological age alone can be misleading, since it does not take into account the evolving dynamics of longevity and the patterns health changes.
As Lloyd indicates, these authors recommend adopting an alternative perspective that considers age and aging in terms of functional capacity. The latter can be measured as "prospective age": the average number of years that people of a given chronological age can still expect to live (i.e., conditional or remaining life expectancy). As people age, their health, disabilities, and cognition tend to be more correlated with their prospective age than with their chronological age.”
“Prospective age”, in fact, is a concept that was introduced in 2010, in an article in the journal Science, by scientists Sergei Scherbov, from the Wittgenstein Center for Demography and Global Human Capital (Vienna), and Warren Sanderson, professor of economics. at Stony Brook University (New York) and academic at the International Institute for Applied Systems Analysis in Luxembourg.
The prospective age compares ages from different periods taking into account the increase in life expectancy, using life tables that we could compare with price indices.
Among the main factors that influence a person's prospective age “is genetic predisposition, which plays an important role in longevity and susceptibility to diseases; lifestyle, social factors such as accessibility to healthcare, socioeconomic factors, social support network; the educational level; the environment and living conditions, the present stress and its management capacity to name the most relevant,” says Tarazona.
The prospective age is set on personal characteristics, such as remaining life expectancy. Scherbov and Sanderson propose considering that a person reaches old age at the age at which his remaining life expectancy is 15 years or less, regardless of his chronological age at that moment: 65, 58 or 73. But physical capabilities and cognitive are also crucial, because the increase in life expectancy implies that the years we spend in good health conditions are also prolonged.
At this point... May I know how many years I have left? Unfortunately, it is not easy. “It is not possible to accurately calculate our prospective age, but it is within our reach to estimate the time we may have left to live,” explains Tarazona. As? “Based on the current state of health, one's own medical history and family history, the results of health examinations performed, adherence to a healthy lifestyle and maintenance of a positive life attitude.”
In any case, "this estimate is not exact and only brings us closer to a notion on which we can articulate, especially in the most unfavorable cases, measures to improve the state of health and quality of life, increasing the probability of greater longevity." "adds the specialist from the La Ribera University Hospital.
The clinical applicability of the concept is erratic at the moment, it is not reliable, according to Tarazona. But from the economic and statistical perspective, this concept gains importance to reliably calculate -and taking into account demographic changes-, pensions and other public resources that will be necessary in the not distant future.
"The prospective age is technically calculated taking into account the changes in the highest ages that a population reaches, from which a fixed amount is subtracted, usually about fifteen years, which is what we could call life expectancy in old age" explains Mercedes Ayuso, professor of Actuarial Statistics at the University of Barcelona (Department of Econometrics, Statistics and Applied Economics, Riskcenter-UB).
With this approach, it no longer makes sense to talk about old age when a fixed age is reached, normally 65 years of age (common in many countries), an age that has traditionally been marked as the beginning of retirement. "With the prospective age vision, the age at which we begin to talk about old age is a mobile age, which will become increasingly older if the time people live from birth increases," Ayuso points out.
Although it is not a widely used concept yet in the design of public policies, "it is used in the literature, for example, when justifying active aging in the workplace and increasing retirement ages. It is a way of reasoning that The 65 years of today are not equivalent to the 65 years of 30 years ago, because now people live longer after that age," according to the economist.
The social and economic implications of this fact, as can be seen, are not minor. As the professor of actuarial statistics reflects, "societies must be prepared for longer life horizons in the population. Technically, the idea of prospective age allows us to take into account changes in life expectancy since the person is born. ; not conditioning the calculation to a fixed age (65 years) that is the same for everyone."
Furthermore, prospective age can, or ideally should, influence how individual people plan for retirement, long-term care, and resource management. We must think not only how long we have lived, but how much we could live. "Citizens must have information about the years they are expected to live, and to do so it is essential to take into account the generation to which they belong (year of birth), and how the probabilities of survival/mortality change generationally speaking (for example, due to health advances). That way they will be able to make forecasts about the needs they will have and the coverage they will require to cover them," comments the economist.
It also advises that citizens be up to date on the pension, health and long-term care coverage that they will have depending on how long they will live. "This will help build long-term savings, also individually," as public coffers should do.
