Discussion of the Paper:

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Discussion of the PaperIDL, the International
Database on LongevityLiving to 100
SymposiumSociety of Actuaries

• Leonid A. Gavrilov, Ph.D.
• Center on Aging
• NORC and University of Chicago
• Chicago, Illinois, USA

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Disclaimer

• This discussion may be incomplete because the
  discussed paper was received only at the Symposium

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Why Supercentenarian Studies are so Important?

• Extreme cases are particularly informative for
  discriminating between competing theories
• (Peter Kapitsa, physicist, Nobel prize winner)
• Extreme cases of longevity are particularly
  informative for discriminating between competing
  theories of aging and longevity

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Historical Note

• Early studies starting with Gompertz (1825)
  himself suggested mortality deceleration and
  leveling-off at advanced ages
• Later studies by British researchers, Greenwood
  and Irwin (1939) suggested that mortality force
  becomes constant at extreme old ages

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M. Greenwood, J. O. Irwin. BIOSTATISTICS OF
SENILITY
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Mortality at Advanced Ages

• Source Gavrilov L.A., Gavrilova N.S. The
  Biology of Life Span
• A Quantitative Approach, NY Harwood Academic
  Publisher, 1991

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Constant failure rate at extreme old ages was
also predicted by the reliability theory of aging
and longevity

• Gavrilov L.A., Gavrilova N.S. The Biology of Life
  Span A Quantitative Approach, NY Harwood
  Academic Publisher, 1991
• Gavrilov, L.A., Gavrilova, N.S. The reliability
  theory of aging and longevity. J. Theor. Biol.
  213, 527-545, 2001.

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Non-Gompertzian Mortality Kinetics of Four
Invertebrate Species

• Non-Gompertzian mortality kinetics of four
  invertebrate species nematodes, Campanularia
  flexuosa, rotifers and shrimp.
• Source A. Economos. A
  non-Gompertzian paradigm for mortality kinetics
  of metazoan animals and failure kinetics of
  manufactured products. AGE, 1979, 2 74-76.

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Non-Gompertzian Mortality Kinetics of Three
Rodent Species

• Non-Gompertzian mortality kinetics of three
  rodent species guinea pigs, rats and mice.
• Source A. Economos. A non-Gompertzian
  paradigm for mortality kinetics of metazoan
  animals and failure kinetics of manufactured
  products. AGE, 1979, 2 74-76.

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Non-Gompertzian Mortality Kinetics of Three
Industrial Materials

• Non-Gompertzian mortality kinetics of three
  industrial materials steel, industrial relays
  and motor heat insulators.
• Source A. Economos. A non-Gompertzian
  paradigm for mortality kinetics of metazoan
  animals and failure kinetics of manufactured
  products. AGE, 1979, 2 74-76.

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Thus, the conclusion of the discussed paper

• Striking feature of these supercentenarian
  survival curves is the seemingly exponential
  decline in survival probabilities
• fits well with the earlier studies and
  theoretical predictions
• (except that these earlier studies are not cited
  in the discussed paper)

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Remaining questions and methodological concerns

• Where is the proof that the list of
  supercentenarians is indeed complete or
  age-ascertainment-bias free?
• Where are the data themselves?
• There are no data in the announced
  www.supercentenarians.org

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Specific question for discussion

• this supercentenarian list is assumed to be
  age-ascertaintment-bias free (Kestenbaum and
  Fergusson, 2002)
• Questions for discussion
• Is this list really bias-free?
• How do we know that it is unbiased?