Background
The elderly population (those aged 65 years or older)
in the USA is expected to double from approximately 35
million today to more than 70 million by 2030 [1]. With
this rapid growth in the number of older Americans, prevention and treatment of chronic diseases of aging will
take on growing importance. Dementia is a disease of
particular concern because the decline in memory and
other cognitive functions that characterizes this condition also leads to a loss of independent function that has
a wide-ranging impact on individuals, families and
healthcare systems. Accurate national estimates of the
current and future prevalence of dementia are essential
for effective planning for the long-term care and medical
costs that will fall to the Social Security, Medicare andother insurance programs for elderly adults in the USA.
To date, five important reports have estimated the prevalence of dementia or Alzheimer’s disease (AD) in the USA
[2–6], all employing extrapolations from a few US communities or from European and Canadian studies. However, studies of other medical conditions, such as stroke,
hypertension and cancer, suggest substantial regional
variation in the occurrence of these conditions throughout the USA [7, 8]. Similar regional variability may occur
for dementia as well. In an attempt to directly determine
the dementia prevalence rate in the USA, we conducted
the Aging, Demographics, and Memory Study (ADAMS),
the first population-based study of dementia to include
individuals from all regions of the country.
Prevalence of Dementia in the
United States: The Aging, Demographics,
and Memory Study