Multidimensional disability/mortality trajectories at ages 65 and over: The impact of state dependence

How dependent is life expectancy at age 65 on one's degree of disability or specific types of functional limitations? Are there significant sex differ ences? For closed-cohorts of males and females in different disability/func tional-status states at age 65, how do their age and disability-specific fu nctional statuses evolve with increasing age? These questions are addressed by analyzing multidimensional disability/mortality trajectories generated using a two-component stochastic process model applied to multivariate long itudinal data from the 1982 to 1994 National Long Term Care Surveys. In thi s model, one component process describes the temporal and age dynamics of a person's functional state and the other describes the risk of death as a f unction of a person's age and stochastically evolving position in the funct ional-status state space. Large differences were found in life expectancy a mong closed cohorts of persons who, at age 65, are in one of seven basic di sability/functional-status states, identified by a multivariate analysis. L arge differences between males and females in life expectancy for the origi n-specific cohorts were also found. While females starting in most states t end to live longer, they are not as likely to return to the healthy, nondis abled state - females also tend to go into institutions at a higher rate th an males.