Demography
Tracking down supercentenarians

On April 12, 2001, Marie-Laure Nadon celebrated her 112th birthday in a long-term care centre in the east end of Montréal. She is the only living woman in Quebec who is a member of the select club of supercentenarians, people who have reached 110 years of age. She is also among the 10 oldest people in the world. "We have traced only four other persons in Quebec who have topped 110 years-all women," says Robert Bourbeau, Professor in the Department of Demography at Université de Montréal.

Together with colleagues Jacques Legaré and Bertrand Desjardins, also demographers, Mr. Bourbeau is tracking down supercentenarians not for the public interest value but out of a scientific interest in extreme longevity. Mr. Bourbeau has calculated that, for the generation born at the end of the 19th century, the probability of celebrating a hundredth birthday was 7 in 1000. The chances of reaching 110 years was 1 in 100,000. "Much better than the chance of winning the lottery," the researcher comments. "Without a doubt, human longevity has increased constantly since the 19th century," notes. Mr. Legaré. "How far can it go? Until recently, 110 seemed to be the absolute, unsurpassable limit. These new cases raise several questions."

The study of extreme longevity comes up against a problem of methodology: how to validate claims and rumours about a person's age? "It may seem strange that in 2001 we have no simple, indisputable method for determining someone's age," says Bertrand Desjardins, research officer in the Department of Demography. Birth registers have only had force of law across Canada since 1921, and five years later in Quebec."

International meetings of demographers interested in extreme longevity are held periodically. "We cannot draw any conclusions with our six or seven cases in 20 years. So we have to join forces with international collaborators and pool our data," Bertrand Desjardins explains. Last year, he presented the first case of a Canadian supercentenarian, Flore Bellerive (Couture). The case reassured French demographers, who had never understood how mankind's oldest specimen, Jeanne Calment, managed to reach the ripe old age of 122 years. Since then, several more supercentenarians have been confirmed. The countries most active in this research are Holland, France, England and most of the Scandinavian countries. Together with the Quebecers, some twenty researchers have created the Arles group (an acronym for Alliance for research into exceptional longevity and survival.)

Researcher : Robert Bourbeau
Phone : (514) 343-5870
Funding : Social Sciences and Humanities Research Council