Background
Dementia is a syndrome in which progressive deterioration in
intellectual abilities is so severe
that it interferes with the person's usual social and
occupational functioning. An estimated 5 to
10 percent of the U.S. adult population ages 65 and older is
affected by a dementing disorder,
and the incidence doubles every 5 years among people in this age
group.
Alzheimer's disease is the most common form of dementia in the
United States. It and related
dementias affect at least 2 million, and possibly as many as 4
million, U.S. residents. Despite its
prevalence, dementia often goes unrecognized or is misdiagnosed
in its early stages. Many
health care professionals, as well as patients and family
members, mistakenly view the early
symptoms of dementia as inevitable consequences of aging.
Some disorders that result in dementia are "reversible or
potentially reversible," which means
that they can be treated effectively to restore normal or nearly
normal intellectual function.
Among the most frequent reversible causes of dementia are
depression, alcohol abuse, and drug
toxicity. In elderly persons, drug use—particularly drug
interactions caused by
"polypharmacy" (simultaneous use of multiple drugs)—is a
common cause of cognitive
decline. Depression also is an underdiagnosed condition in this
population.
The majority of dementias, including Alzheimer's disease, are
considered nonreversible. Even
for these conditions, correct diagnosis of the problem in its
early stages can be beneficial.
Correct recognition can prevent costly and inappropriate
treatment resulting from misdiagnosis,
and give patients and families time to prepare for the
challenging financial, legal, and medical
decisions that may lie ahead. In addition, many of the
nonreversible dementias such as
Alzheimer's disease include symptoms that can be treated
effectively (for example, incontinence,
wandering, depression).
According to the National Institute on Aging, an estimated $90
billion is spent annually for
Alzheimer's disease alone, and the noneconomic toll is
incalculable. Although State and local
governments and the Federal Government bear some of the economic
burden, largely through
Medicare and Medicaid, a substantial proportion is borne by
families that provide unpaid care.
Changes caused by dementia may advance relentlessly over many
years, creating not only deep
emotional and psychological distress but practical problems
related to caregiving that can
overwhelm affected families.
Addressing the Problem
In 1992, the Agency for Health Care Policy and Research, a
Federal Government agency within
the Public Health Service, convened a panel of private-sector
experts to develop a clinical
practice guideline on screening for Alzheimer's disease and
related dementias. This topic was
selected because:
- Dementia in the adult population is a serious and growing
medical, social, and economic
problem.
- Alzheimer's disease and related dementias exact a massive
toll in health care costs,
disability, and lost productivity of both patients and family
caregivers.
- Early symptoms of dementia are commonly overlooked,
mistakenly attributed to normal
aging, or misdiagnosed.
- Failure to diagnose early-stage dementia can result in
needless and possibly harmful
treatment.
After extensive literature searches and meta-analyses, the panel
decided to focus on early
detection of dementia in persons exhibiting certain
characteristics or triggers that signal the need
for further assessment, rather than recommend general screening
of segments of the population,
such as those over a certain age. The panel made this decision
after concluding that: