TIME-VARYING COVARIATES IN MODELS OF HUMAN MORTALITY AND AGING - MULTIDIMENSIONAL GENERALIZATIONS OF THE GOMPERTZ

Models of mortality and aging depend on assumptions about physiologica l change even if they are not made explicit. Standard models, like the Gompertz, often fail to describe mortality at extreme ages, suggestin g a need for biologically more detailed and flexible models. One solut ion is to model the interaction of time-varying covariates with mortal ity to better describe the age dependence of mortality, test hypothese s about the relation of physiological change and mortality, and use lo ngitudinal data to generalize assumptions about physiological change. This model is applied to (a) a 34-year follow-up of risk factors and m ortality and (b) a 9.5-year follow-up of function and mortality from l ongitudinal surveys of the U.S. elderly population.