A hundred years ago in 1918, Alexander Graham Bell started looking at centenarians – those who live up to and beyond 100 years.
Earlier studies looked at families in 14th-19th century China and Swedish families between 1500 and 1829. But Bell’s study was unique. Although Bell became famous for inventing the telephone, he was also one of the first to study centenarians. He based his work on records collected by Reuben Walworth (1864) using detailed 8,797 records of descendants of William Hyde who died in 1681 in the US.
While most of these early descendants died before age 40, a testament to the hazardous environmental conditions prevailing at the time, a small minority survived till very old age. Overall, Bell found more females dying before the age of 40 (childbearing age), after which they began gaining an advantage. He identified that the longevity of parents (more so for fathers) related to the longevity of their children. Interestingly, he found that longer lived parents had more children. While fathers that married younger lived longer.
Today centenarians are still rare, but more common than they were in Bell’s time. Centenarians are, in fact, the fastest growing population group in post-industrialised countries.
Centenarians are mainly women, with seven out of 10 of the total number. Few are obese, especially men, and few smoked, although around one in five smoked in the past.
Jeane Louise Calment, the longest-lived person who died at the age of 122, smoked a couple of cigarettes a day until she was 117, and she only stopped because she became blind and had difficulty lighting up. One in seven lucky centenarians experience no significant changes in their thinking.
Many centenarian women have children after the age of 35 years. At least half of centenarians have close relatives and grandparents who also achieve very old age. So it seems genes play a strong role in exceptional longevity, but it does not determine it.
The 2000-2011 rate of centenarians per 100,000 people is variable, from 36.8 in Japan, 26.6 in Italy, 25.8 in France, 20.3 in the UK, 17.4 in Canada, 17.3 in the US, 15.1 in Germany and 3.8 in Russia. Given that the population in Malta is expected to top 450,000 in 2016, then we would expect to see between 17 and 162 centenarians. But how many centenarians do we have?
By 2050, the National Statistics Office anticipates more than 700 Maltese centenarians
As an avid Maltese centenarian watcher, Michael Bonnici, a retired politician from Żebbuġ, scours newspaper obituaries looking for centenarians. Bonnici estimates there are 24 living centenarians in Malta today.
The Times of Malta obtained 2011 census data from the National Statistics Office which identified 31 residents aged 100 or over. The oldest Maltese person to have ever lived seems to be a woman from Balzan, who died in 1999 at the age of 109. By 2050, the National Statistics Office anticipates more than 700 Maltese centenarians. There are no records of a Maltese ever becoming a supercentenarian – over 110 years of age.
But there is a problem with estimating very old age. In 1986, given continued claims of extreme age, Norris and Ross McWhirter, the editors of The Guinness Book of World Records, noted that: “No single subject is more obscured by vanity, deceit, falsehood and deliberate fraud than the extremes of human longevity.” Stephen Coles reports how the US Census Bureau dropped its estimate of centenarians from 2,700 in 1990 to 1,400 centenarians in 2000 after checking the dates of birth with the Social Security Administration. And then, even this number is likely to be exaggerated.
Faulty data also seems to be a problem in Malta. In January 2016, Leonard Callus wrote about one 120-year-old woman registered to vote in Balzan; two 116-year old women from Gżira and St Paul’s Bay; and two 115-year-old women from Msida and St Julian’s. In total there were 134 voters between 100 and 120, only 55 of which were Maltese citizens. These inaccuracies in reporting extreme long age have received a lot of attention from demographers.
Longevity myths reached a peak in 1970 because of a series of articles in the National Geographic by Alexander Leaf. Later, Leaf himself acknowledged that people lied to him in order for them to improve their social status and to promote local tourism.
As a consequence, more careful checks are being implemented, resulting in 1999 in a new methodology for asserting true age. This methodology, first used in Sardinia, is now used to determine the ‘Blue Zones’, areas throughout the world where centenarians cluster.
Despite an incredible opportunity for Malta to have such long-lived examples, we only have half the rate of centenarians of what we see in the rest of Europe. Why are they dying early?
To examine this further, we need to start maintaining better records and to promote projects that monitor and engage these unique individuals so that we can learn their secrets for posterity.
Mario Garrett is the author of Politics of Anguish: How Alzheimer’s disease became the malady of the 21st century. He will be delivering a talk at the University of Malta on February 9 from 5.30 to 7.30pm on ‘Methodological critique of Alzheimer’s disease: Bad science, good politics’.