[ad_1]
That sounds absurd. Immediate good sense can tell us that the older we get, the greater the risk of dying. Indeed, the risk of dying due to age increases over the years, resulting in an upward curve. However, according to a study published in the journal Science above 105 years this curve slows to the point of displaying a plateau area. And the scientists concluded that they analyzed the data of four thousand Italians, at the top of the longevity of the human species there is still no ceiling in sight.
The title of the article is "The plateau of human mortality: demographics of the pioneers of longevity". And the conclusion seems, at first glance, bizarre. The researchers say that at the top of the scale of life, from the age of 105 (if we get there), there is a plateau. We know that every step we take on this ladder, every passing year, exposes us to a greater risk of falling, we read death. But now, the team of researchers led by demographer Elisabetta Barbi, of Sapienza University in Rome, Italy, and the statistician of the Department of Political Science of the University of Rome III, tell us that for the very old, the increased risk of dying because of age tends to slow down. The risk remains high (there at the top where the probability of dying is equal to the probability of staying alive) but does not increase more than that.
Why? Are people who reach this age the strongest and most resilient by various factors (physical and psychological) and therefore "hold on" better and longer? In the article, the researchers do not give clear and definitive answers. For a firm conclusion, it was necessary to have a larger sample, to study more and better these centenarians and other supercentenarians and more (over 110 years), the study authors point out. They note, however, that it is possible to observe similar patterns of extreme age-specific mortality in other species and suggest that structural and evolutionary explanations may be common. And, on the one hand, they point out that improving the care we now devote to "extremely old" people can help mitigate the increase in mortality, but also that this plateau could be the result of genetic factors. The evolutionary theories of senescence, including the theory of accumulation of mutations and age-related gene burden effects, also offer promising ingredients for a joint explanation of the exponential and exponential increase. plateaus of extreme age. in the article that concludes with the statement that further studies are needed to achieve "an empirical clarity that contributes to the ongoing theoretical progress."
Regardless of the reasons that may justify the phenomenon, the article published in Science confirms that the plateau of human mortality exists. "In this study, we present estimates of risk rates based on the data of all Italians aged 105 or older between 2009 and 2015 (born between 1896 and 1910), totaling 3836 documented cases," they explain in the report. Article, concluding that "the risk contour lines were essentially constant after the age of 105 years." "Our estimates are free of aggregation artifacts that limit previous studies and provide the best evidence so far for human mortality trays. "
For this complex exercise in demographics and statistics, researchers used data recently collected and validated by the Italian National Institute of Statistics. From there, it was possible to follow the "individual survival trajectories of all Italians aged 105 or over between 1 January 2009 and 31 December 2015". "For a number of reasons, these data allow us to estimate mortality at extreme ages with accuracy and precision that were not possible before," they say.
The Limit and the Secret of Longevity
The data analysis, according to which mortality rates increase exponentially with age, begins to slow down after 80 years and reach a plateau after 105 years. That is to say, at this stage of life, the odds that a person will die between one birthday and the other are in the order of 50/50. Although disconcerting, one can even admit the existence of this plateau at the top of the walks of life facing these centenarians as multiresistant examples of the human species or, in a more simplistic version, as rather "hard" "To reach this age of three figures for this very reason, to be able to support it then (in a adapted version of the survival of the strongest). However, the most disturbing is that the researchers conclude that it is not yet possible to define a limit of human longevity. In 2016, a team of researchers led by geneticist Jan Vijg of the Department of Genetics at the Albert Einstein School of Medicine in New York, USA, used demographic databases to: conclude that the limit The maximum longevity of our species has been reached and is set at around 115 years. According to this article published in the journal Nature the probability of exceeding 125 years is less than one in 10,000, less than 0.01%.
Adriano Miranda
The upward trend curve that shows the increase in average life expectancy begins in the nineteenth century. The human species has gained about 30 years of life over the last century. The debate is about stopping this line. To what extent, with the advancement of technologies and responses to public health problems, have we been able to reduce mortality in the early years and throughout life and increase longevity? The statistical analysis work of the US research team suggested a response, the 115-year-old. In the article now published in Science experts claim that there is no end in sight, there is no limit established for longevity of the human species
"The increasing number of people with exceptional longevity and the fact that their mortality beyond 105 seems to decline in different age groups – lowering the mortality threshold or delaying the age at which it appears – strongly suggests that longevity continues to increase over time and that a threshold, if any, has not been reached, "conclude the authors, concluding that the results of this study "contribute to a recently reactivated debate on the existence of a maximum longevity set for humans, subscribing to the doubt that this limit is already in view." 19659002] Without certainty , there remains the guarantee that such a debate on longevity will not stay here. In an article by Nature on the study published now, several experts are already discussing the results of this article. Some people consider that the absence of a limit of human longevity is simply "biologically improbable". "We have basic limitations imposed by our body," says Jay Olshansky, a biochemist at the University of Illinois at Chicago, USA, citing as an example cells that do not multiply (like neurons) and who continue to die. it ages, which necessarily imposes a limit.
And even the question of the threshold at the top of the staircase of life seems consensual. While some experts believe that this study presents the strongest evidence so far on plateaus in the mortality of very old people, others claim that a more comprehensive analysis is needed to draw definitive conclusions.
Despite the many questions and discussion that the theme of aging can raise, there is clear evidence. At present, the world will have something like 500,000 people aged 100 or older (and predictions indicate a doubling of that number with each passing decade). On the other hand, the fact that women live longer than men is indisputable. The explanations (and also the jokes that are made in this regard) are the most diverse and range from environmental factors to hormonal or other. In this study, to avoid any doubt about this gender imbalance, among the 3836 Italians aged 105 or over, 3373 were women and 463 men. So, for those who want to live long, long time to be a woman will clearly be an advantage.
On this, another striking example: in the list of 15 people who have exceeded 115 years since 1990, published in the book Supercentenarians published in the International Database on Longevity, contained only two men. One of the women on this list was the Portuguese Maria de Jesus (1893-2009) who was known when the Guinness Book of Records concluded that she was the oldest person on the planet in November 2008 She died on January 2, 2009 with 115 years old. According to the most recent statistics from the National Institute of Statistics, in 2017 there were 4268 people in Portugal with one hundred or more of these 2600 were women. The French Jeanne-Louise Calment was known to have been the longest person on our planet, specifically 122 years and 164 days. He died in 1997.
At Work Supercentenarians were life stories of these examples of extreme longevity, highlighting a few common points. Coincidence or not, most supercentenarians did not have children or had only one, many liked to eat sweets (noting a preference for chocolate), most did not smoke, some drank small amounts Alcohol per day (a glass of Porto for example) and almost all were considered active and well disposed. There was a doubt in the air: is the secret of longevity a recipe that includes, among others, chocolate, a little alcohol and a good mood? This is unlikely. Obviously, the longest human life on the planet will be the result of a mysterious combination of luck and genetics. Not being the reason, chocolate, alcohol and good humor are at least the reward after climbing so many steps.
Source link
