1.1. Data validation: an essential step

Within the expanding group of centenarians, recent years have seen the establishment of a new, even more long-lived group: people aged 105 or over. On 1 January 2023, this group had an estimated 2,000 members in France [2], equalling the number of centenarians in 1981. It is difficult to count individuals who reach these very advanced ages, as their numbers remain small, and the reported ages in the census may be incorrect. Vital records provide a more accurate means to count deaths at age 105 or above, after checking the validity of the recorded data. Over the last two decades, an international team of researchers has developed a new data source, the International Database on Longevity (IDL [3], see Box 1) for this purpose. For France, the data are drawn from the National Directory for the Identification of Natural Persons (RNIPP), a database managed by the National Institute of Statistics and Economic Studies (INSEE) that contains the list of all named individuals, born in France or abroad, who ­possess a social security number [4]. When one of these individuals dies in France, or their death abroad is reported to the French authorities, the death is registered in the RNIPP. For the French data in the IDL, INSEE provides INED with an annual list of persons born in France (metropolitan France and overseas departments) who died at age 105 or above in the preceding two years. These data are then systematically verified in full for all individuals who reached age 110 or over, and in part for those who died at ages 105-109. This involves checking the accuracy of the characteristics reported in the RNIPP (dates and places of both birth and death) by matching them against against individual vital records (birth and death certificates) of each person. While errors are relatively rare among deaths below age 110 (0.7%), a much larger share of cases at this age or above are excluded after verification (around 8% [5]).

1.2. Growing numbers of deaths beyond age 105

RNIPP data show trends over time in the annual number of deaths at ages 105 or above (Figure 1). While representing a minute fraction of the over 600,000 deaths recorded annually in France (under 0.15%) their number has surged in recent years, rising from just a handful of individuals in the late 1980s to 924 in 2020. The dip observed in 2021 and 2022 does not reflect a drop in the probability of reaching age 105, but rather the arrival at this age of the smaller cohorts born during the First World War. The collapse in births (by more than 40%) between 1915 and 1919 continues to have repercussions 105 years later. The fact that the decline is not already apparent in statistics from 2020 is likely due to the increase in deaths during the COVID-19 epidemic.

The vast majority of people who die at age 105 or above are women (843 women and 81 men in 2020, or 10 times more women). This impressive ratio is entirely due to excess male mortality, which operates throughout the lifespan, particularly at working ages, decreasing the share of males as the generation gets older. Births have an opposite effect, as slightly more boys than girls are born each year. Immigration, which could modify the sex ratio, has no effect here, as only individuals born in France are included in the IDL for France.

The predominance of women in the pyramid of deaths at age 105 or above is even more impressive. Figure 2 clearly shows the male-female contrast in numbers of deaths, along with the concentration of male deaths at the ‘youngest’ ages, with the male bars dwindling almost to invisibility beyond age 108.

1.3. Beyond age 110: Supercentenarians

People who reach the age of 110 are known as ‘supercentenarians’. While still a rare event, it has become much more frequent in recent decades (Fig. 3). No deaths in this age range are recorded in the RNIPP before 1987, and it would be another two decades before the number reached double digits. It has since grown considerably, while fluctuating widely due to the small annual numbers concerned. In 2022, 39 deaths at age 110 or above were recorded. Predictably, the overwhelming majority were women: 38 out of the 39. This predominance has remained constant over time, as can be seen in Figure 3, where the curve for all deaths at age 110 or above is almost identical to the curve for women’s deaths at those ages. At the department level in metropolitan France, the ratio of deceased supercentenarians to the total population ranges from 0 to 17 per million inhabitants, but with no clear geographical pattern. Guadeloupe and Martinique, with 44 and 36 supercentenarians per million inhabitants, respectively, stand out clearly from the rest of France, however (see Box 2).

Both the increase in the number of supercentenarians in recent years and the predominance of women at these ages have been observed in all countries where it is possible to validate age at death (see Box 1). The number itself depends, of course, on the size of the population, and more exactly on the size of the cohorts born 110 years earlier. France outperforms England and Wales, for example, for which comparable data are available. In 2020, the latest year available for England and Wales, the ratio of individuals who died at age 110 or above (11) to the size of the 1906–1910 birth cohorts was 2.4 per million, versus 6.9 per million in France. This French supercentenarian advantage, which remains to be confirmed in comparisons with more countries, is consistent with Natalie Blanpain’s finding that the probability of becoming a centenarian is higher in France than in 15 other European countries [2].

More anecdotally, two of the four individuals worldwide recognized as having lived more than 118 years are French women (along with one woman in the US and one Japanese woman): Jeanne Calment, the oldest recorded human being at age 122 years and 5 months, and more recently Lucile Randon, who died in 2023 just before her 119^th birthday (118 years and 11 months).

1.4. Does the risk of death level off at very advanced ages? 

In addition to counting verified cases and validating the extreme ages attained by a small number of individuals, demographers study deaths at age 105 and above in order to refine their estimates of the risk of death at very advanced ages. While it is now possible to accurately trace the mortality curve up to age 100 (for cohorts born in 1901–1905, a woman aged 100 had a one-in-three chance of dying before her next birthday), risks of death beyond that age are still fluctuating and uncertain (Figure 4), particularly for men. At these advanced ages, the numbers of observations remain insufficient to settle an ongoing debate among researchers. Some argue that ­mortality continues to increase exponentially with age, as seen at younger ages, while others hold that this increase slows, or even levels off to reach a mortality plateau [6]. In coming years, as the quantity of reliable data in the IDL increases, it should become possible to determine the shape of the mortality curve at very advanced ages with less uncertainty.