Ricerc@Sapienza

Theories about biological limits to life span and evolutionary shaping of human longevity depend on facts about mortality at extreme ages, but these facts have remained a matter of debate. Do hazard curves typically level out into high plateaus eventually, as seen in other species, or do exponential increases persist? In this study, we estimated hazard rates from data on all inhabitants of Italy aged 105 and older between 2009 and 2015 (born 1896–1910), a total of 3836 documented cases. We observed level hazard curves, which were essentially constant beyond age 105.

One of the oldest but still debated question in
evolutionary demography is about the shape of
the mortality trajectory for humans at extreme
ages. Several studies suggested that for humans
adult and early-old death rates rise exponentially
up to about age 80 and thereafter decelerate. Other
studies, however, found that the exponential
increase of the mortality risk with age continues
at advanced ages in humans. Recent studies on
exceptionally long-lived individuals have shown
that the trajectory of mortality levels off at