ABSTRACT
The mean life expectancy of people with Down syndrome is less than that of the general population. However, it has increased from a life span of less than 10 years in the early 1900s to almost 50 years more recently. Twenty per cent or more of people with Down syndrome may be over the age of 55 years at any one time. This improvement has made the prevalence of age-related health problems apparent. The most important of these is the risk of developing Alzheimer-like neuropathological change and dementia of the Alzheimer type.
