We propose a model of aging and health deficit accumulation model with an infinite time horizon and a steady state of constant health. The time of death is uncertain and endogenous to lifestyle and health behavior. This setup can be conceptualized as a strive for immortality that is never reached. We discuss adjustment dynamics and show that the new setup is particularly useful to understand aging of the oldest old, i.e. of individuals for which morbidity and mortality have reached a plateau. We then show how the existence of a steady state can be used to perform comparative dynamics exercises analytically. As an illustration we investigate the effects of more expensive health investment and of advances in medical technology on optimal short run and long run health behavior.
comparative dynamics endogenous mortality life-expectancy medical progress