ABSTRACT
Would we all succumb to dementia if we lived long enough? This is a question posed frequently by the general public to the scientific community. It is of importance both to society, as the proportion of the population made up by older people grows, and to individuals who fear the consequences of prolonged lives with associated frailty. The answer, if it is answerable, will depend on a multitude of factors. This chapter cannot review even a small fraction of the diverse literature relevant to this question, including evidence from biomedical research on ageing, clinical and biomedical research on dementias and also the relevant literature on chronic diseases and causes of death in earlier life. Instead the chapter looks at the types of evidence that have been used to address the question and explores the question itself.
