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:
- No evidence exists to support recommending some of the most
frequently used screening
tests over others.
- None of the tests has a high sensitivity for early or mild
dementia.
- No evidence supports the efficacy of a general screen for
Alzheimer’s disease or related
dementias, given the lack of unequivocally effective treatment
and the difficulty of
recognizing early dementia.
The panel subsequently limited its scope specifically to the
subject of recognition and initial
assessment and therefore did not address differential diagnosis,
management, or treatment issues
after diagnosis.
Principal Objective
The panel’s principal objective was to increase the likelihood of
early recognition and assessment
of a potential dementing illness so that (1) concern can be
eliminated if it is not warranted; (2)
treatable conditions can be identified and addressed
appropriately; and (3) nonreversible
conditions can be diagnosed early enough to permit the patient
and family to plan for
contingencies such as long-term care.
Specifically, the panel’s goals were to:
- Improve the detection of Alzheimer’s disease and related
dementias in their early stages
in persons exhibiting certain signs and behaviors.
- Educate health professionals, patients, and their families
about symptoms that suggest the
need for an initial assessment for a dementing disorder.
- Identify areas for further research on early recognition of
dementia.
Findings
The panel’s major findings include:
- Certain triggers should prompt a clinician to undertake an
initial assessment for dementia
rather than attribute apparent signs of decline to aging.
- An initial clinical assessment should combine information
from a focused history and
physical examination, an evaluation of mental and functional
status, and reliable
informant reports. It also should include assessment for delirium
and depression.
- An assessment instrument known as the Functional Activities
Questionnaire is a
particularly useful informant-based measure in the initial
assessment for functional
impairment.
- Among effective mental status tests, the Mini-Mental State
Examination, the Blessed
Information-Memory-Concentration Test, the Blessed
Orientation-Memory-Concentration Test, and the Short Test of
Mental Status are largely
equivalent in discriminative ability for early-stage
dementia.
- Clinicians should assess and consider factors such as
sensory impairment and physical
disability in selection of mental and functional status tests,
and other confounding factors
such as age, educational level, and cultural influences in
interpretation of test results.
In asymptomatic persons who have possible risk factors (e.g.,
family history and Down
syndrome for Alzheimer’s disease), the clinician’s judgment and
knowledge of the patient’s
current condition, history, and social situation (living
arrangements, support services, isolation)
should guide the decision to initiate an assessment for
dementia.
Initiating an Assessment
For a diagnosis of dementia, current criteria in the Diagnostic
and Statistical Manual of Mental
Disorders, Fourth Edition (DSM-IV), require evidence of decline
from previous levels of
functioning and impairment in multiple cognitive domains, not
solely memory. Because
evidence of decline in previous abilities is critical in
establishing dementia, a personal
knowledge of the patient is invaluable to the clinician in
assessing symptoms and interpreting
results of an initial assessment for dementia.
A focused history is critical in the assessment for dementia. It
is particularly important to
establish the symptoms’ mode of onset (abrupt versus gradual);
progression (stepwise versus
continuous decline; worsening versus fluctuating versus
improving), and duration.
A focused physical examination, including a brief neurological
evaluation, is an essential
component of the initial assessment. Special attention should be
placed on assessing for those
conditions that cause delirium, since delirium represents a
medical emergency. During the
focused physical examination, health care providers should be
alert to signs of abuse and neglect
of patients by caregivers and report suspected abuse to the
proper authorities.
Informant reports (information obtained from family members or
caregivers) can supplement
information from patients who have experienced memory loss and
may lack insight into the
severity of their decline. Health care providers, however, should
consider the possibility of
questionable motives of informant reports, which may exaggerate,
minimize, or deny symptoms.
Brief mental status tests can be used but they are not
diagnostic. They are used to (1) develop a
multidimensional clinical picture; (2) provide a baseline for
monitoring the course of cognitive
impairment over time; (3) reassess mental status in persons who
have treatable delirium or
depression on initial evaluation; and (4) document multiple
cognitive impairments as required
for a diagnosis of dementia.
Assessing for Depression
Depression can be difficult to distinguish from dementia, and it
can coexist with dementia.
Changes in memory, attention, and the ability to make and carry
out plans suggest depression,
the most common psychiatric illness in older persons. Marked
visuospatial or language
impairment suggests a dementing process. The clinical interview
is the mainstay for evaluating
and diagnosing depression in older adults. Two self-report
instruments with established
reliability and validity are the Geriatric Depression Scale (GDS)
and the Center for
Epidemiological Studies Depression Scale (CES-D).
Interpreting Findings
Three results are possible from the combination of findings from
assessments of mental and
functional status: (1) normal, (2) abnormal, and (3) mixed.
When results of both mental and functional status tests are
normal and there are no other clinical
concerns, reassurance and suggested reassessment in 6 to 12
months are appropriate. If concerns
persist, referral for a second opinion or further clinical
evaluation should be considered.
When both mental and functional status tests yield findings of
abnormality, further clinical
evaluation should be conducted. However, a laboratory test should
not be used as a screening
procedure or part of an initial assessment. Laboratory tests
should be conducted only after (1) it
has been confirmed that the patient has impairment in multiple
domains that is not lifelong and
represents a decline from previous levels of functioning; (2)
delirium and depression have been
excluded; (3) confounding factors such as educational level have
been considered; and (4)
medical conditions have been be ruled out.
Mixed results—abnormal findings on the mental status test
with no abnormalities in
functional assessment or vice versa—call for further
evaluation. For example:
- Patients who have abnormal results on only the mental
status test require more complete
testing. Results that indicate possible neuropsychiatric or
systemic neurological problems
call for referral to an appropriate specialist.
- Patients who have declining function but normal mental
status test results require either
(1) further neurological evaluation for systemic neurological
diseases or (2) psychiatric
or psychological evaluation if evidence suggests depression or
other emotional problems.
The Role of Neuropsychological Testing
Neuropsychological tests can examine performance across different
domains of cognition. This
broad battery of tests can help in identifying dementia among
persons with high premorbid
intellectual functioning, discriminating patients with a
dementing illness from those with focal
cerebral disease, and differentiating among certain causes of
dementia.
The Importance of Followup
Followup, with assessment of declining mental function, may be
the most useful diagnostic
procedure for differentiating Alzheimer’s disease from normal
aging. For this reason, the mental
status test should be repeated over a period of 6 to 12 months.
In cases of referral, it is important
to make sure that test results and medical records follow the
patient from the specialist back to
the referring clinician.
Key Points About Alzheimer’s Disease
Key Points About Alzheimer’s Disease
- Although changes in memory or cognition may accompany
normal aging, significant
impairment and disability are not a part of normal aging.
- It is important for clinicians, as well as patients and
family members, to recognize
symptoms that should trigger an initial assessment for
dementia.
- Some causes of dementia can be treated effectively to
eliminate or greatly improve
cognitive performance.
- Among older persons, depression and interactions from
multiple medications are two
common and highly treatable causes of dementia symptoms.
- An initial assessment for dementia can (1) lead to
effective treatment of causes; (2)
prevent unnecessary and possibly harmful treatment resulting from
misdiagnosis; and (3)
avoid the trauma of a diagnosis of dementia or Alzheimer’s
disease where it does not
exist.
- The prolonged course of deterioration found in many
dementias takes a major emotional,
psychiatric, and physical toll among family members and
caregivers.
- Learn more about symptoms that may indicate early-stage
dementia and how to conduct
an initial assessment. Read Recognition and Initial Assessment
of Alzheimer’s Disease
and Related Dementias, Clinical Practice Guideline
No. 19, and use its companion Quick
Reference Guide for Clinicians. Give the Consumer
Version to patients, family members,
and other caregivers.
For Patients
- Dementia is different from normal aging. Only certain tests
can show that difference.
Symptoms that suggest Alzheimer’s disease or a related dementia
should be brought to
the attention of the family’s health care provider as soon as
possible.
- Some memory and other problems can improve or disappear
with appropriate treatment.
- Although there is not yet a clearly effective treatment for
Alzheimer’s disease, resources
are available to help patients and families cope with this
condition and prepare for the
future.
- Order the consumer booklet, Early Alzheimer’s
Disease: from the U.S. Government’s
Agency for Health Care Policy and Research. It provides
information about the early
stages of Alzheimer’s disease and similar illnesses. It also
includes a list of resources
where readers can find out more about the medical, financial, and
social support services
that are available in their communities.
- The Agency for Health Care Policy and Research also has a
Clinical Practice Guideline
and a Quick Reference Guide for health care providers
about early identification of
Alzheimer’s disease and other forms of dementia.
Symptoms That Might Indicate Dementia
Does the person have increased difficulty with any of the
activities listed below? Positive
findings in any of these areas generally indicate the need for
further assessment for the presence
of dementia.
- Learning and retaining new information. For example:
is more repetitive; has more
trouble remembering recent conversations, events, appointments;
more frequently
misplaces objects.
- Handling complex tasks. For example: has more
trouble following a complex train of
thought, performing tasks that require many steps such as
balancing a checkbook or
cooking a meal.
- Reasoning ability. For example: is unable to respond
with a reasonable plan to problems
at work or home, such as knowing what to do if the bathroom
flooded; shows
uncharacteristic disregard for rules of social conduct.
- Spatial ability and orientation. For example: has
trouble driving, organizing objects
around the house, finding his or her way around familiar
places.
- Language. For example: has increasing difficulty
with finding the words to express what
he or she wants to say and with following conversations.
- Behavior. For example: appears more passive and less
responsive; is more irritable than
usual; is more suspicious than usual; misinterprets visual or
auditory stimuli. In addition
to failure to arrive at the right time for appointments; the
clinician can look for difficulty
discussing current events in an area on interest and changes in
behavior and dress. It
might also be helpful to follow up on areas of concern by asking
the patient or family
members relevant questions.
Guideline Development
The Agency for Health Care Policy and Research convened an
18-member private-sector,
interdisciplinary panel composed of psychologists, psychiatrists,
neurologists, an internist,
geriatricians, nurses, a social worker, and consumer
representatives. The panel conducted
extensive literature searches to identify empirical studies of
assessment of mental status
instruments for differentiating persons with and without dementia
and instruments used in the
assessment of persons with Alzheimer’s disease. It conducted
additional literature searches
related to assessment of functional impairment and risk factors
for dementia and conducted
meta-analyses. The panel also held a public hearing to give
interested organizations, individuals,
and agencies an opportunity to present oral or written testimony
for the panel’s consideration.
The results of the literature reviews and meta-analyses were used
to develop a draft guideline.
Copies were distributed for two peer review cycles. Reviewers
were selected to represent a broad
range of disciplines and clinical practice areas. A total of 109
reviewers submitted comments,
which were collated and reviewed by the panel co-chairs and used
to develop the final guideline.
Current Availability
You can now obtain copies of the Consumer Version free
through InstantFAX, which operates
all day every day. Using a fax machine equipped with a touch tone
telephone, dial (301)
594-2800, push 0 and follow the voice prompts. The code for the
publication is 967123.
Future Availability
Additional guideline information will be available later this
year (Winter 1996) in several forms:
- Clinical Practice Guideline, intended for the health
care provider, contains a discussion
of the issues and the panel’s findings and recommendations, with
supporting evidence
and references. It also includes a series of tables and a flow
chart summarizing the panel’s
recommended approach to early recognition and initial assessment
of suspected
dementia.
- Quick Reference Guide for Clinicians, also intended
for health care providers, is a brief
summary of and companion piece to the Clinical Practice
Guideline. It provides
highlights of initial assessment and interpretation of findings
and presents the tables and
flow chart.
- Consumer Version, published in English and Spanish,
is a brochure for patients, their
families, and the general public that describes the problem,
outlines procedures for
identifying dementia in its early stages, and provides resource
information for those who
must deal with a diagnosis of probable Alzheimer’s disease or a
related dementia.
To obtain further information on the availability of the Quick
Reference Guide or Consumer
Version, call the AHCPR Publications Clearinghouse at (800)
358-9295 or write to:
Alzheimer’s Disease
AHCPR Publications Clearinghouse
P.O. Box 8547
Silver Spring, MD 20907-8547
Single and bulk copies of the Clinical Practice Guideline,
Recognition and Initial Assessment of
Alzheimer’s Disease and Related Dementias, may be purchased,
when available, from the U.S.
Government Printing Office by calling (202) 512-1800.
The Clinical Practice Guideline, Quick Reference Guide, and
Consumer Version will also be
available on the Internet through the AHCPR Home Page. You can
access the guideline products
by using a Web browser, specifying the URL http://www.ahcpr.gov/guide, and clicking on
Clinical Practice Guidelines Online.
AHCPR, a part of the U.S. Public Health Service, is the lead
agency charged with supporting
research designed to improve the quality of health care, reduce
its costs, and broaden access to
essential services.
U.S. Department of Health and Human Services
Public Health Service
Agency for Health Care Policy and Research
2101 East Jefferson Street, Suite 501
Rockville, MD 20852
AHCPR Publication No. 97-R123
September 1996