Download Preventing dementia

Dementia 2010
Mild cognitive impairment is
defined as impairment of
_______ beyond that expected
for a person’s age.
(A) Information processing speed
(B) Memory
(C) Executive functioning
(D) Attention
Answer
• (B) Memory
Dementia is a syndromal term
that refers to which of the
following?
(A) Loss of cognitive function
associated with impaired daily
functioning
(B) Marked change in emotions
and temperament
(C) Neurologic dysfunction
(D) All the above
Answer
• (D) All the above
An imaging report notes “white
matter changes consistent with
microvascular disease”; this
_______ the diagnosis of
vascular dementia.
(A) Establishes (B) Does not
establish
Answer
• (B) Does not establish
Lewy body dementia is
characterized by:
1. Insidious onset and relentless
progression of cognitive dysfunction
2. History of stroke
3. Fluctuating cognitive impairment
4. Dysautonomia with unexplained
falls
5. Formed and/or
microhallucinations
(A) 1 (B 2,3 (C) 3,4,5 (D) 2,3,4,5
Answer
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3. Fluctuating cognitive impairment
4. Dysautonomia with unexplained falls
5. Formed and/or microhallucinations
(C) 3,4,5
The hallmark of frontotemporal
dementia is:
(A) Marked change in personality
or language
(B) Early severe cognitive
impairment
(C) Loss of executive functioning
Answer
• (A) Marked change in personality or
language
The diet believed to be
most beneficial for brain
health is the equivalent of
the _______ diet.
(A) South Beach (B)
Pritikin (C) Mediterranean
(D) Vegan
Answer
• (C) Mediterranean
If cognitive impairment
resolves after treatment of
depression, there is little
risk that the patient will
later develop
dementia.
(A) True (B) False
Answer
• (B) False
A longer interval between the
diagnosis of depression and that
of Alzheimer disease (AD)
_______ the risk for
developing AD.
(A) Increases
(B) Decreases
(C) Has no association with
Answer
• (A) Increases
In evaluating a patient for dementia,
which of the following are
significant findings?
1. Significant weight loss
2. Urinary incontinence
3. Unexplained falls
4. History of stroke, seizure, or head
injury with loss of consciousness
(A) 1,3 (B) 1,3,4 (C) 3,4 (D) 1,2,3,4
Answer
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1. Significant weight loss
2. Urinary incontinence
3. Unexplained falls
4. History of stroke, seizure, or head injury
with loss of consciousness
• (D) 1,2,3,4
Select the correct statement about
obtaining neuroimaging of
patients with depression in mid to
late life:
(A) All require neuroimaging
(B) None require neuroimaging
(C) No hard and fast rule exists
Answer
• (C) No hard and fast rule exists
Of the following, which is
considered the key indicator that
a patient is suffering from
delirium?
(A) Impaired recall
(B) Visuospatial impairment
(C) Fluctuating attention
(D) Visual hallucinations
Answer
• (C) Fluctuating attention
Thiamine deficiency typically
presents as enlargement of the
_______ on magnetic resonance
imaging.
(A) Sulci
(B) Mammillary bodies
(C) Caudate nuclei
(D) Subarachnoid space
Answer
• (B) Mammillary bodies
Comatose patients without
involvement of the deep gray
matter of the thalamus are
typically able to:
(A) Localize painful stimuli
(B) Track faces or fingers
(C) Sit or stand
(D) All the above
Answer
• (A) Localize painful stimuli
In patients displaying altered
mental status, nystagmus across
the vertical plane typically
indicates:
(A) Metabolic disorder
(B) Delirium
(C) Parasympathetic overactivity
(D) Structural pathology
Answer
• (D) Structural pathology
Symptoms of bleeding into the
subarachnoid space include:
(A) Chemical meningitis and
delirium
(B) Aphasia and tremor
(C) Horizontal nystagmus and
myoclonus
(D) All the above
Answer
• (A) Chemical meningitis and delirium
Patients with Alzheimer disease
typically exhibit loss of recent
memory, but unlike with
delirium, their
_______ is frequently preserved.
(A) Attention span
(B) Visuospatial cognition
(C) Abstract reasoning
(D) Motor skills
Answer
• (A) Attention span
Patients who score _______ on a
Mini-Mental State Examination
(MMSE) are considered to have
mild
dementia.
(A) 30 (B) 20 (C) 10 to 20 (D)
<10
Answer
• (B) greater than or equal to 20
Studies show that driving
abilities significantly
deteriorate once a patient
with dementia scores
_______ on
the MMSE.
(A) <25 (B) <20 (C) <15
(D) <10
Answer
• (B) <20
Acting as a caregiver for an
individual with dementia is
associated with a high likelihood
of developing:
(A) Post-traumatic stress disorder
(B) Acute stress disorder
(C) Anxiety and depression
(D) Adjustment disorder
Answer
• (C) Anxiety and depression
In patients with advanced
dementia, feeding tubes reduce
the rates of aspiration pneumonia
and are associated
with measurable increases in
survival.
(A) True (B) False
Answer
• (B) False
Delerium
• the ability to provide lucid history with normal
orientation, attention, recent recall, and speech eliminates
the possibility of delerium
• A history that suggests cognitive problem necessitates
methodical mental status examination
• In the setting of altered mental status, signs on general
examination indicate presence of delirium and differentiate
sympathetic nervous system overactivity from
underactivity
• in delirium, acute cognitive changes occur over hours to
days
• fluctuating attention key indicator; may affect all aspects
of cognition, including memory, language, and visuospatial
testing
Diagnostic tests
• memory tests unreliable after diagnosis of confused
state
• digit span testing—in young adults, average recall spans 7
forward and 4 backward
• forward testing typically sufficient
• digit span recall declines slightly with age (80-yr-old
should still recall 6 digits forward)
• test of recent memory—patients must retain information
for short period (eg, recall 3 different objects 5 min later)
• sympathetic overactivity states—eg, alcohol withdrawal,
hyperthyroidism, drug effect
• sympathetic underactivity—caused by eg, sedative
hypnotics
• history from witnesses frequently presents conflicting
information due to fluctuating nature of syndrome
Risk factors for delirium
• age >65
• baseline cognitive dysfunction (lowers threshold
for delirium; prolongs recovery) establish true
baseline by contacting caretakers
• diminished hearing or vision
• poor general health
• bladder catheters (associated urinary tract
infections)
• new medications
• Restraints
• sleep deprivation;
• screen for metabolic causes and sepsis
Dementia
• poor intellectual or cognitive function with no
disturbance of consciousness
• older patients at risk for both delirium and dementia
• patients with dementia typically
• display social behavior and engage in basic conversation
• similarities and differences—useful bedside test assesses
abstract thinking; eg, ask patient to explain differences and
commonalities between apples and oranges
• delirium impairs even basic abstract thought
• cognitive functioning— established by questioning family
and friends after establishing cognitive baseline
• ask about functional cognitive activi activities engaged in
by patient (eg, finances)
Dementia
• Visual hallucinations—frequently attributed to metabolic disorders
(eg, alcohol withdrawal)
• typically related to neurodegeneration in patients with Parkinson’s
disease
• Lewy body dementia—frequently causes visual hallucinations
• may account for 15% to 25% of patients diagnosed with Parkinson’s
disease
• visual hallucinations increase over time; responds to carbidopalevodopa (Sinemet), resulting in frequent misdiagnosis of Parkinson’s
disease
• carbidopa-levodopa causes visual hallucinations in absence of
pathology
• as neurodegeneration progresses, even low doses may trigger
hallucinations
• stroke and visual deficit—typically produces inability to see, rather
than hallucinations in visual field; neurodegenerative symptoms
overlap with symptoms of delirium, but persist significantly longer
Thiamine deficiency
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presents with enlarged mammillary bodies on MRI
metabolic cause of delirium with highly specific treatment
frequently underrecognized
in autopsy studies, only 10% of patients accurately
diagnosed before death expecting presence of all 3 major
indicators (confusion, limitation of eye movements, truncal
ataxia) frequently leads to missing diagnosis of thiamine
deficiency
• suspect when confusion of unknown cause present with
malnourishment
• deficiency typically impairs absorption, necessitating
intravenous or intramuscular thiamine
Encephalopathy
• clonus—typically elicited by rapid movement of joint or
hyperreflexia
• frequently occurs at ankle, occasionally entire leg
• rhythmic and induced by movement
• myoclonus—almost uniformly presents with asynchronous
features (eg, twitching, but not rhythmic)
• ongoing seizure—especially with rhythmic twitching of
digit or ocular deviation to one side with nystagmoid
movement
• dystonia—presents as abnormal, fixed posture (typically of
leg or trunk) with no rhythmic movements
• postural tremor—fine high-frequency tremor when limb
held against gravity; subsides at rest
Seizures and delirium
• delirium may persist after seizure into postictal
state
• mimics sedative-hypnotic drug effect, but may
indicate sympathetic overactivity
• evaluate patient for earlier seizure
• frequent subtle seizures (particularly
• partial-complex type) may induce prolonged
postictal state
• actual seizure activity often too short-lived for
observation
• specific metabolic disorders predispose patients to
both seizures and delirium (eg, severe
hypoglycemia)
Receptive aphasia
• patients frequently fabricate words
(neologisms) or speak nonsensically
• occasionally clinically indistinguishable from
delirium (neuroimaging requiered to confirm
diagnosis)
• majority of patients displaying receptive aphasia
present with hemiparesis or visual field cuts
• screen for aphasia assesses repetition, naming, and
comprehension (varies with severity of delirium)
• Meaningful response to any questions establishes
comprehension, ruling out receptive aphasia
Brain Injury
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subdural hematoma—compresses brain
Neurologic structures may shift across midline
In most severe cases, medial portion of temporal lobe extends and compresses brainstem and third
cranial nerve
common in patients with no history of falling
computed tomography (CT) of head recommended for patients at high risk
nonfocal neurologic examination—common
neurologists have difficulty predicting findings associated with compression of brain
findings may refer to hemisphere opposite subdural hematoma
Early herniation—may present with evidence of partial third cranial nerve palsy (parasympathetic
nerve fibers affected, producing dilated pupils)
suspicion warranted even without pupil indications
prompt imaging required once brainstem symptoms manifest (to rule out incipient brainstem
compression)
coma—patients without involvement of deep gray matter of thalamus typically maintain ability to
localize painful stimulus
in absence of verbal communication, physicians may assess volitional activity by applying sternal
rub
patients who reach toward sternum receive diagnosis of encephalopathic state (ie, not comatose)
brainstem reflexes—differentiate “dense” encephalopathy from coma
pupils correspond to upper and midbrain;
corneal function and “doll’s eyes” reflex correlate to middle brainstem
pons; respiration and cardiovascular function correlate to lower brainstem
mid-position fixed pupils—typically indicates late herniation compromising both sympathetic and
parasympathetic nerves in brainstem
Altered mental status
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general examination—should focus on distinguishing delirium from alternative diagnosis
Look for tachycardia, fever, stiff neck, tremor, asterixis, or myoclonus (common accompaniments of delirium or encephalopathy)
patients with limited functioning may retain ability to track face or finger
horizontal nystagmus frequently indicates metabolic disorder
nystagmus in vertical plane typically indicates structural pathology (most often in posterior fossa requires immediate imaging)
measure sensory function and withdrawal on both sides of body (eg, with painful stimulus to nail beds)
facial response to painful stimulus may reveal asymmetry
motor examination—patients typically uncooperative
check limb movement against gravity
attempt to get patient walking or standing;
destructive processes in cerebellum (eg, hemorrhage) may selectively interfere with ability to sit or stand (no changes in limb
coordination)
making patient sit and stand allows assessment for midline cerebellar findings
Cerebrospinal fluid (CSF) examination—underutilized
screens for infectious meningitis (acute and chronic) recommended with even slightest suspicion
indicated in unexplained delirium after imaging fails
assessment for xanthochromia critical
bleeding into subarachnoid space produces chemical meningitis and delirium
blood frequently not visible (depends on when hemorrhage occurred)
rule of halves— xanthochromia appears 0.5 day after hemorrhage, peaks at 0.5 wk, begins to disappear after 0.5 mo
meningitis— neoplastic meningitis typically accompanied by other systemic signs of advanced neoplasm
other types include chemical meningitis
patient may display evidence of vasculitis, sarcoidosis, or other uncommon disorders
HIV encephalopathy—causes impaired attention, forgetfulness, and white matter lesions
other sources of CNS involvement require exclusion
herpes simplex encephalitis—may present with only confusional state and abnormal behavior (due to temporal lobe involvement)
indicated by fever, headache, and focal findings; patients with abnormal CSF (pleocytosis and elevated protein in polymerase
chain reaction)
typically receive acyclovir
Types of Dementia
• Alzheimer disease—recent memory loss
prevalent, but attention span typically preserved in
mild cases, patients recall forward digit spans of 6
to 7
• Vascular dementia—fairly common; occurs with
extensive vascular disease and shows extensive
vascular changes on neuroimaging
• frontotemporal dementias—produce changes in
behavior and anxiety; patients typically perform
well on mental status examinations but exhibit
deeper cognitive changes
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Driving safety
older individuals estimated to comprise 25% of drivers by 2030
responsible for 7% of accidents, but
15% of traffic fatalities
mixed evidence associates mild cognitive impairment and mild dementia with
increasedmcrash rates
dementia inevitably affects driving safety
Physicians must assess for increased safety risks
loss of driver’s license significant and affects quality of life (associated with poorer
health and depression)
several states make reporting mandatory; assessing driver safety—
document driver history
ask about recent accidents and tickets, getting lost, frequency of driving, and selflimiting behavior (eg, driving only for specific purposes)
Objective second individual should be asked about driving safety (in private)
American Medical Association guide—assesses vision, motor function, and cognition;
includes visual acuity testing, rapid walking, and range of motion test (ie, ability to look
over shoulder)
cognitive tests include trails B and clock draw
clock draw—patient asked to draw clock face on blank paper and illustrate time using
both hemispheres
Driving Safely
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trails tests—assess executive functioning
Trails A involves connecting series of numbers in order
trails B connects interspersed letters and numbers (high difficulty)
American Academy of Neurology review (2000)— evidence-based
review of Alzheimer disease and driving risk
recommended patients with MMSE <20 not drive
studies correlate scores <20 with worse driving ability
Absolute cutoff score not defined
MMSE scoring combined with results from clock draw and trails tests
before making decision
behind-the-wheel testing—gold standard; typically administered by
driving rehabilitation specialist
Usually not covered by insurance (costs $200)
State mandatory reporting laws—physicians immune from litigation in
these states
Increased supervision
• independent activities of daily living
• (IADL)—primary focus when assessing increased need for supervision
• includes complex tasks (eg, shopping, paying bills, personal grooming,
housekeeping)
• financial activities typically impaired first
• ask about ability to handle checkbook;
• activities of daily living (ADLs)—include eating, dressing, toileting,
and transferring; safety of independent living—determined on case-bycase basis
• need for assistance with 1 core ADLs typically necessitates 24-hr
• supervision (not absolute)
• physicians should ask family members about home accidents (eg, items
left unattended on stove) and wandering behavior
• caregiving—informal care provided by family members and friends
• Caregivers require multidisciplinary support, including health care
• providers, social workers, home care workers, and clergy
Increased supervision
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physicians frequently unaware of patients in caregiving role
study found 24% of patients who see family physicians were caregivers
associated with high incidence of depression (30%-60%) and anxiety (17%); caregivers
rate personal health status significantly lower than controls
overall mortality risk among elderly spousal caregivers expressing burden or stress rises
by 63% (vs controls)
20% of caregivers forced to leave jobs
31% of families reported losing all or most of savings due to patient’s illness
Assisting caregivers—recognition of patients in caregiving role critical
provide disease-based education
watch for common associated health effects (eg, depression)
offer links to community resources; provide referrals for bereavement counseling when
necessary
community resources— include home care, senior centers, and adult day programs
day programs geared toward dementia and provide respite for caregivers
Alzheimer’s Association and Area Agency on Aging provide online locators of respite
care
National registries for dementia link with local police departments to provide alerts for
lost patients
Advanced stages
• all patients with dementia eventually have difficulty eating;
pocketing food—behavior caused by apraxia
• recommend preparing caregivers for inevitable feeding issues and
providing information about behavioral indicators
• helpful feeding techniques—
• increased feeding assistance
• stable and upright feeding position
• smaller portions (on plate and fork); softening food (eg, with gravy)
• feeding tubes—multiple studies show no benefit for advanced dementia
• associated with chronic diarrhea, dislodgment problems, discomfort,
increased risk for aspiration pneumonia, and increased use of restraints
• no measurable increases in survival found
Cognitive impairment
associated with normal
aging
• Loss of memory for words and names
• slowed processing speed
• difficulty sustaining attention when faced
with competing environmental stimuli
• no functional impairment
Mild cognitive impairment
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memory impairment beyond that expected for person’s age
memory impairment increasing over last 6 to 12 mo
other cognitive functions generally unimpaired
daily function not significantly impaired
not dementia
subjective complaint not usually useful (real changes more apparent to
others than to self)
• 80% of people with mild cognitive impairment already have emerging
dementia that will convert to frank dementia within 5 yr (usually
Alzheimer disease [AD])
• prediction of who will convert currently difficult, but in near future,
biomarkers may be available to accompany clinical assessment
• study indicates high level of psychopathology (eg, anxiety, irritability,
depression, paranoia)
Clinical management
• no treatments approved by Food and Drug
Administration (FDA)
• monitor alcohol use, medications (eg,
analgesics, psychotropics, over-the counter
drugs)
• provide prophylaxis for cardiovascular risk
factors
• treat anxiety and affective disorders, but
eschew benzodiazepines
Unapproved treatments
• acetylcholinesterase inhibitors studied
exhaustively
• most results negative
• some definitive studies of donepezil (Aricept)
showed positive effect
• “but not enough to define practice”;
• Discuss both known and unknown effects of
acetylcholinesterase inhibitors with patient and
family
• no other agents (eg, vitamins, memantine)
adequately tested or show evidence of benefit
Dementia
• syndromal term that refers to loss of
cognitive function associated with impaired
daily functioning,
• eventual marked change in emotions and
temperament
• in late stages, with neurologic dysfunction
• of 50 to 100 causes of dementia, AD by far
most common
Warning signs of early
dementia
• difficulty with learning and retaining
information, vocabulary, and orientation
• trouble with daily tasks
• changes that interfere with function
• behavior changes (eg, passivity, irritation,
suspiciousness)
• concerns should trigger evaluation of
cognition, function, and behavior
Barriers to early
diagnosis of AD
• average time between appearance of initial
symptoms and diagnosis of possible
dementia 4 yr
• average time between diagnosis and
initiation of therapy 2 yr
• shortness of visits and constraints
• on reimbursement most significant barriers
Differential diagnosis
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includes AD
vascular dementia
Dementia with parkinsonian features
Lewy body dementia
and frontotemporal dementia
Alzheimer disease
• insidious onset
• relentless progression of cognitive
dysfunction (usually, but not always,
memory)
• with subsequent generalization to other
domains
• (eg, language, visuospatial function,
executive function, problem-solving,
insight, sequencing of events, prioritizing)
• minimal psychopathology in early stage
• no prominent neurologic abnormalities
Vascular dementia
• risk factors same as those for stroke (eg,heart disease,
arrhythmia, congestive heart failure, hypertension,
dyslipidemia, diabetes, smoking, family history of stroke)
• history of focal or nonfocal events
• Focal findings on examination
• supported by imaging
• Imaging reports of “white matter changes consistent with
microvascular disease” not diagnostic
• such changes seen in 80% of normal older individuals;
diagnosis difficult accounts for only 5% of patients with
dementia
• look for pattern of stabilization, decline, stabilization,
decline
Dementia with parkinsonian features
• requires specialist to distinguish between AD with
parkinsonian features, Lewy body dementia, and
Parkinson disease with dementia
• Lewy body dementia: indicated by slowly
progressive, but peculiarly fluctuating course “like
… chronic delirium”
• characterized by fluctuating cognitive impairment,
atypical and nonprogressive parkinsonian features
(with onset of dementia after that), and
dysautonomia with unexplained falls
• hallmark—vivid psychopathology with formed
hallucinations and/or microhallucinations
Frontotemporal dementia
• early but mild cognitive impairment
• hallmark—marked change in personality or
language
Evaluation of possible
dementia
• patient history
• Differential diagnosis (looking at cognition, function, and
behavior)
• Mini-Mental State Examination (MMSE)
• category retrieval
• clock draw (patient asked to draw clock set to, eg, 11:10)
• complete blood count; imaging studies; many optional
tests (eg, genetic testing
• Structural magnetic resonance imaging (sMRI)
• biomarkers in blood and urine
• functional positron emission tomography (fPET) expected
to become routine in 5 yr
Impact of AD
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cost of care—currently $120 billion/yr in
United States
by 2050, $1.2 trillion/yr
physical and psychologic toll on caregivers
high risk for major depression and medical
morbidity associated solely with demands
of providing care
Brain fitness strategies
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epidemiologic studies suggest medications for other physical conditions may confer
brain health or protection against dementia (controversial; speaker does not recommend)
no evidence for benefit of nutriceuticals; stress reduction
depression highly correlated with cognitive dysfunction
pearl—if first onset of depression occurs late in life, patient has high likelihood of
developing AD
physically active adults have lower risk for AD (requires equivalent of 40-min brisk
walk 3 times/wk)
other lifestyle choices—avoid sports with potential for brain trauma
smoking cessation
moderate consumption of red wine (4-14 4-oz servings/wk) possibly beneficial
equivalent of Mediterranean diet healthiest diet (brightly colored fruits and vegetables;
fish
olive oil
Dairy in moderation
minimize red meat and simple carbohydrates);
mental activity (must involve mental effort [“something stimulating that you don’t
ordinarily do”])
Memory or other cognitive training techniques (benefit can be significant, but limited to
specific function addressed)
Things to Remember
• brain aging inevitable
• many age-related changes mitigated by
healthy lifestyles
• memory-training techniques (eg, look, snap,
connect technique)
Depression and Dementia
• depression and dementia are syndromes, not
etiologies
• Diagnostic and Statistical Manual of Mental
Disorders, Fourth Edition (DSM-IV)
• definition of dementia—impairment in memory
and 1 other domain of cognition
• these must cause functional impairment
• deficits not solely due to delirium
• definition of major depressive syndrome
• presence of 5 of 9 symptoms that cause functional
impairment unrelated to bipolar disorder
• symptoms cannot be better accounted for by
another condition
5 of the 9 following symptoms
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1) depressed mood most of the day, nearly every day, as indicated by either subjective report (e.g.,
feels sad or empty) or observation made by others (e.g., appears tearful). Note: In children and
adolescents, can be irritable mood.
(2) markedly diminished interest or pleasure in all, or almost all, activities most of the day, nearly
every day (as indicated by either subjective account or observation made by others)
(3) significant weight loss when not dieting or weight gain (e.g., a change of more than 5% of body
weight in a month), or decrease or increase in appetite nearly every day. Note: In children, consider
failure to make expected weight gains.
(4) insomnia or hypersomnia nearly every day
(5) psychomotor agitation or retardation nearly every day (observable by others, not merely
subjective feelings of restlessness or being slowed down)
(6) fatigue or loss of energy nearly every day
(7) feelings of worthlessness or excessive or inappropriate guilt (which may be delusional) nearly
every day (not merely self-reproach or guilt about being sick)
(8) diminished ability to think or concentrate, or indecisiveness, nearly every day (either by
subjective account or as observed by others)
(9) recurrent thoughts of death (not just fear of dying), recurrent suicidal ideation without a specific
plan, or a suicide attempt or a specific plan for committing suicide
Etiologies
• dementia—include AD, cerebrovascular disease,
Lewy body disease, and other brain diseases (eg,
HIV infection)
• unknown whether depression causes dementia,
• but depression often earliest symptom of AD
• depression—include AD, cerebrovascular disease,
substance and prescribed medication use (eg,
alcohol, interferon),
• genetic predisposition
• reaction to psychosocial stressors
Relationship between depression
and dementia
• Cognitive impairment can be feature of
depressive episode, but does not always
resolve with treatment of depression
• conversely, depression also common (50%)
in dementia
• recent meta-analysis showed depression
approximately doubles chance of having
Alzheimer’s dementia
• unknown whether depression is prodrome
of or independent risk factor for dementia
(evidence exists for both)
Pseudodementia
• occurs when individual appears to be
demented due to severity of depression
• in study of older patients, 70% converted to
true dementia within 5 yr, even if cognitive
impairment resolved with treatment of
depression
Depression as risk factor
• longer interval between diagnoses of
depression and AD associated with
increased risk for development of AD
• on autopsy, more plaques and tangles seen
in brains of patients with lifetime history of
depression
Possible trajectories linking
depression and dementia
• 1) depression results in no cognitive deficit, and cognition
remains stable over time
• 2) some shrinking of hippocampus occurs in both
depression and dementia
• perhaps resulting in mild cognitive impairment that
remains stable over time
• 3) patient already has neuropathology of AD that may
progress to mild cognitive impairment and later to AD
• 4) combination of AD neuropathology and cerebrovascular
disease may cause frontal striatal damage, which leads to
depression;
• 5) cerebrovascular disease in and of itself results in
depression and vascular dementia
Frontotemporal dementia
• initial symptoms can mimic those of
depression
• overlapping symptoms include emotional
blunting
• decline in personal hygiene
• Distractibility and impersistence,
hyperorality
• dietary changes,
• weight changes,
• altered speech output
Evaluation
• watch for red flags of dementia
• obtain detailed history, including
personality changes, risk factors for
dementia (eg, substance use, HIV infection)
• do thorough review of systems, including
significant weight loss, urinary
incontinence, unexplained falls, and history
of stroke, seizure, or head injury with loss
of consciousness
• perform complete physical and neurologic
examinations
Mental status examination
• include MMSE for evaluation of cognition in all
patients
• if red flags occur, consider more extensive
evaluation
• Modified MMSE: adds 4 new test items and more
scoring gradations to standard MMSE
• Clock-drawing task: several available; provides
information that can indicate presence of cognitive
impairment
• Montreal Cognitive Assessment (MoCA): takes
about same time as MMSE, with some additions
• Available free at www.mocatest.org
Laboratory evaluation
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complete blood count
Electrolyte levels
liver function tests
thyroid-stimulating hormone level
vitamin B12 and folate levels
syphilis screen (either rapid plasma reagin [RPR] or Venereal Disease
Research Laboratory [VDRL])
depending on circumstances, consider measures of inflammation
(erythrocyte sedimentation rate [ESR] or C-reactive protein [CRP])
Autoimmune disease (rheumatoid factor [RF] or antinuclear antibody
[ANA])
HIV test
Lyme disease test
lumbar puncture,
and/or electroencephalography
Neuroimaging
• no hard-and-fast rule on whether to obtain
neuroimaging on patients with depression in
mid to late life
• if red flags seen, consider computed
tomography (CT) of head or MRI
(preferred)
• if concern high for frontotemporal
dementia, consider PET or single proton
emission computed tomography (SPECT
• Medicare approved to distinguish
Alzheimer dementia from frontotemporal
Misdiagnosis of delirium
• delirium common in acute-care settings and may
present with depressive symptoms;
• study found that of 67 consecutive patients
referred to psychiatry for evaluation of depression,
• 28 delirious
• common symptoms included low mood, feelings
of worthlessness, and frequent thoughts of death
• Delirium initially considered in differential
diagnosis of referring physician in only 3 patients
Preventing dementia
•
•
•
•
•
•
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potentially modifiable risk factors include
Smoking
high blood pressure in midlife
High body mass index in midlife
high cholesterol in midlife
Diabetes
unknown whethter controlling these risk factors
prevents dementia, but may help
• Mediterranean diet (rich in polyunsaturated fats
and antioxidants) appears protective for heart
disease and possibly for cognition
Preventing dementia
• Key components of Mediterranean diet: ample
fruits and vegetables
• healthy fats (eg, olive oil, canola oil)
• Small portions of nuts
• red wine in moderation (study suggests same
effect with any alcohol
• lower quantity recommended for women than for
men)
• fish on regular basis
• minimal red meat
• Other cognitive protective factors: physical and
mental exercise
Treatment
• if unsure whether patient has depression,
dementia, or both
• treat for depression first and monitor for
response
• in general, antidepressants have favorable
risk/benefit profiles and are effective