Alzheimer's disease (AD) is associated with a substantial reduction in life expectancy, and mortality has long been evaluated as part of the natural history of this progressive disease. Survival time also plays an important role in projecting the future public health costs of AD. There is now considerable evidence linking mortality in AD with the severity of cognitive impairment and the level of disability in common activities of daily living (Bowen et al., 1996; Jagger et al., 1995; Moritz et al., 1997); established predictors of mortality in AD are listed in Table 1. However, the relationship between mortality and other disease characteristics has received less attention.