Introduction: The Biodemography of Complex Relationships Among Aging, Health, and Longevity

Handbook of Sociological Science: Contributions to Rigorous Sociology

“…For example, Ukraintseva et al (2016) note that the influence of a particular genetic variant on longevity may be negative, neutral or positive depending on context. The contributions in Yashin et al (2016) demonstrate how the connections between health, aging and longevity can be studied with existing longitudinal data that include both genetic and nongenetic factors. Others have examined genetic effects on fertility (Kohler et al 1999(Kohler et al , 2006Rodgers & Kohler 2002;Tropf et al 2015).…”

A Systems Level Explanation for Gompertzian Mortality Patterns is provided by the “Multiple and Inter-dependent Component Cause Model”

“…Our model also provides temporal trajectories of mortalityrisk for the individual. These results may give insight into understanding how biological age evolves stochastically within the individual, and how this in turn leads to a natural heterogeneity of biological age in a population.Here µ(t) is the mortality rate, also known as the "force of mortality", "failure rate" or "hazard rate" [11,9,12] and t equals chronological age, i.e., time since birth. The Gompertz Law has two parameters: R 0 is the hypothetical mortality rate at birth, and b is the "Gompertz coefficient"[13] that determines the rate of increase of the exponential term.Apart from its application to mortality rate, the Gompertz Law is also able to describe patterns in disease incidence rates [14,15,16], as well as more abstract measures such as failure rates of computer code [17] and termination rates of self-avoiding random walks in a random network [18].…”

“…Common for such models is an underlying stochastic process describing either accumulation or depletion of a physical entity. Some models focus on a specific molecular or cellular component [24,14], while other models describe more abstract entities such as vitality or frailty [11,20,12,13], and the stochastic process may therefore be interpreted as, e.g., accumulation of damage or depletion of capacity (also termed resilience or redundancy). It is difficult to assert whether the individual mechanistic models mimic a sufficiently generalizable system.…”

“…Here µ(t) is the mortality rate, also known as the "force of mortality", "failure rate" or "hazard rate" [11,9,12] and t equals chronological age, i.e., time since birth. The Gompertz Law has two parameters: R 0 is the hypothetical mortality rate at birth, and b is the "Gompertz coefficient"[13] that determines the rate of increase of the exponential term.…”