October 15, 2011 ◆ Volume 84, Number 8
one individual user of the Web site. All other rights reserved. Contact firstname.lastname@example.org for copyright questions and/or permission requests.
American Family Physician 895
Evaluation of Suspected Dementia
B. BRENT SIMMONS, MD, and BRETT HARTMANN, MD, Drexel University College of Medicine,
DANIEL DEJOSEPH, MD, The Commonwealth Medical College, Scranton, Pennsylvania
20 years, and this increase will bring a higher
prevalence of dementia.1 Early identification
of cognitive impairment can help patients
and their physicians to enact appropriate
advance care planning, identify comorbidi-
ties and secondary causes of cognitive dys-
function, and discuss initiation of medical
therapy. The U.S Preventive Services Task
Force recommends cognitive assessment
if cognitive impairment or deterioration is
suspected.2 However, primary care physi-
cians often cite time constraints as a barrier
to performing this assessment; as a result,
dementia may go unrecognized.3 This arti-
cle addresses the assessment of suspected
dementia, including a review of practical
tools for evaluating cognitive impairment
and geriatric depression.
he proportion of persons in the
United States older than 65 years
will grow from 12 percent to
more than 20 percent in the next
Epidemiology and Risk Factors
After 65 years of age, the lifetime risk of
developing dementia is approximately 17 to
20 percent; 70 percent of patients with
dementia have Alzheimer disease, 17 percent
have vascular dementia, and 13 percent have
a combination of dementia with Lewy bod-
ies, Parkinson-related dementia, alcoholic
dementia, or frontal lobe dementia.4,5 The
transitional state between normal cognition
and early Alzheimer disease is called mild
cognitive impairment, which is defined as
memory impairment without meeting crite-
ria for dementia. Each year, 10 to 15 percent
of patients with mild cognitive impairment
develop Alzheimer disease.6 Alzheimer dis-
ease affects 5.3 million Americans, and is
the sixth leading cause of death.4 Median
survival time after diagnosis of dementia is
Risk factors for dementia include age,
family history of dementia, apolipoprotein
E4 genotype, cardiovascular comorbidities,
chronic anticholinergic use, and lower edu-
cational level.8-10 The greatest risk factor for
dementia is increasing age. In persons 71 to
79 years of age, the prevalence is approxi-
mately 5 percent, increasing to 37 percent in
persons older than 90 years.5 Having a col-
lege education has been shown to delay cog-
nitive dysfunction by two years, compared
As the proportion of persons in the United States older than 65 years increases, the preva-
lence of dementia will increase as well. Risk factors for dementia include age, family history of
dementia, apolipoprotein E4 genotype, cardiovascular comorbidities, chronic anticholinergic
use, and lower educational level. Patient history, physical examination, functional assessment,
cognitive testing, laboratory studies, and imaging studies are used to assess a patient with sus-
pected dementia. A two-visit approach is time-effective for primary care physicians in a busy
outpatient setting. During the first visit, the physician should administer a screening test such
as the verbal fluency test, the Mini-Cognitive Assessment Instrument, or the Sweet 16. These
tests have high sensitivity and specificity for detecting dementia, and can be completed in as
little as 60 seconds. If the screening test result is abnormal or clinical suspicion of another dis-
ease is present, appropriate laboratory and imaging tests should be ordered, and the patient
should return for additional cognitive testing. A second visit should include a Mini-Mental
State Examination, Geriatric Depression Scale, and verbal fluency and clock drawing tests, if
not previously completed. (Am Fam Physician. 2011;84(8):895-902. Copyright © 2011 Ameri-
can Academy of Family Physicians.)
Downloaded from the American Family Physician Web site at www.aafp.org/afp. Copyright © 2011 American Academy of Family Physicians. For the private, noncommercial use of
902 American Family Physician
Volume 84, Number 8 ◆ October 15, 2011
setting” in screening for dementia. J Geriatr Psychiatry
Neurol. 2008; 21(4): 250-260.
26. Aprahamian I, Martinelli JE, Neri AL, Yassuda MS. The
clock drawing test: a review of its accuracy in screening
for dementia. Dement Neuropsychol. 2009; 3(2): 74-81.
27. American Geriatrics Society. A guide to dementia
diagnosis and treatment. http://dementia.american
geriatrics.org/. Accessed August 22, 2010.
28. Knopman DS, DeKosky ST, Cummings JL, et al. Practice
parameter: diagnosis of dementia (an evidence-based
review). Report of the Quality Standards Subcommit-
tee of the American Academy of Neurology. Neurology.
2001; 56(9): 1143-1153.
29. Sheikh JI, Yesavage JA. Geriatric Depression Scale
(GDS): recent evidence and development of a shorter
version. In: Clinical Gerontology: A Guide to Assess-
ment and Intervention. New York, NY: Haworth Press;
30. Marc LG, Raue PJ, Bruce ML. Screening performance
of the 15-item geriatric depression scale in a diverse
elderly home care population. Am J Geriatr Psychiatry.
2008; 16(11): 914-921.
31. Almeida OP, Almeida SA. Short versions of the geriatric
depression scale: a study of their validity for the diagnosis
of a major depressive episode according to ICD-10 and
DSM-IV. Int J Geriatr Psychiatry. 1999; 14(10): 858-865.
32. American Psychiatric Association. Treatment of Patients
with Major Depressive Disorder. 3rd ed. Washing-
ton, DC: American Psychiatric Association; 2000.
GuideChapToc_7.aspx. Accessed May 24, 2011.
33. Clarfield AM. The decreasing prevalence of reversible
dementias: an updated meta-analysis. Arch Intern Med.
2003; 163(18): 2219-2229.
34. Braffman B, Drayer BP, Anderson RE, et al. Dementia.
American College of Radiology. ACR Appropriateness
Criteria. Radiology. 2000; 215 suppl: 525-533.
35. De Meyer G, Shapiro F, Vanderstichele H, et al.;
Alzheimer’s Disease Neuroimaging Initiative. Diagnosis-
independent Alzheimer disease biomarker signature in
cognitively normal elderly people. Arch Neurol. 2010;
36. Engler H, Forsberg A, Almkvist O, et al. Two-year
follow-up of amyloid deposition in patients with
Alzheimer’s disease. Brain. 2006; 129(pt 11): 2856-2866.
37. Ishii K. Clinical application of positron emission tomog-
raphy for diagnosis of dementia. Ann Nucl Med. 2002;