Transcript Screening For Cognitive Impairment

Diagnosis and Initial
Management of
Dementia
Nicolas Szecket & Shabbir Alibhai
Updates by Sharif Missiha, PGY2
AIMGP, MSH
December 9, 2004
Objectives
Definition of dementia
Basic work-up of dementia
Role of neuroimaging
“Cognitive-enhancing” drug therapy
Ethical issues in dementia
Selected References Diagnosis
Practice Parameter: Diagnosis of dementia.
Report of the Quality Standards
Subcommittee of the American Academy of
Neurology. Neurology 2001; 56:1143-53
Folstein MF, Folstein SE, McHugh PR. “Minimental state”. A practical method for grading
the cognitive state of patients for the clinician.
J Psychiat Res 1975; 12:189-98.
Selected References Treatment
Canadian Consensus Conference on
Dementia. Management of dementing
disorders. Can Med Assoc J 1999; 160(12
Suppl)
Mayeux R, Sano M. Treatment of
Alzheimer’s disease. N Engl J Med 1999;
341:1670-79
Practice parameter: Management of
dementia. Report of the Quality Standards
Subcommittee of the American Academy of
Neurology. Neurology 2001; 56:1154-66.
The Case
82 y.o. female recently discharged from
GIM with CAP
Episodes of fluctuating LOC and
confusion at initial hospital presentation
Resolved in hospital with treatment of
pneumonia/hypoxia and low-dose
Haloperidol
The Case
PMH
COPD x 5 years
Type II Diabetes Mellitus
Osteoarthritis
Medications
puffers
Glyburide 2.5 mg BID
Tylenol PRN
The Case
Lives with daughter
Progressive memory loss over 2 years
Patient repeats herself, occasionally
disoriented
Forgets to take some of her medications
Daughter is concerned about mother having
‘senile dementia’ and asks you to “check it
out”
The Case
Physical Examination
BP 130/70 HR 80 reg RR 18
Cardio/resp exam normal
Abdominal exam normal
Neurological exam no focal deficits, absent
ankle jerks, downgoing toes
Question 1
Does this woman have dementia?
Definition of Dementia: DSM-IV
Progressive decline in memory AND at least one
other cognitive area

language, orientation, attention, praxis (skilled motor
function), visuo-spatial, abstraction, executive function
Impairment of social, occupational, or personal
function
Change from baseline
In the absence of depression or clouding of
consciousness (i.e. delerium)
See DSM-IV
Epidemiology of Dementia
From the Canadian Study of Health & Aging:
2.4% of Canadians aged 65-74
11.1% aged 75-84
34.5% aged 85+
Affects both sexes
Increasing prevalence in long-term care
Underdiagnosed or misdiagnosed in 20%

Misperception of “normal” aging process
Can Med Assoc J 1994; 150:899-913
Why Bother Making a
Diagnosis?
Common illness, huge burden for patient,
family, and health care system
Potentially reversible in small number
“Cognitive-enhancing” drug therapy now
available
Prognostic implications (long-term planning re
placement, estate, advance directives, etc.)
Question 1
Does this woman have dementia?
Possibly. Not enough information
to make diagnosis
Question 2
What else should be done at the
initial assessment?
Answer:
• Further dementia history
• Physical exam
• Mental status examination
Initial Assessment
General Dementia History
Date of onset/nature of symptoms
Pre-morbid level of functioning
Nature of progression (if any) - rapid/gradual
deterioration vs. “step-wise”
Family history of dementia
Use of CNS toxic drugs
Head injury (especially recent)
Depressive symptoms
Initial Assessment
ADLs (bathing, dressing, feeding, toileting,
transferring, ambulation)
Instrumental ADLs (shopping, cooking,
finances, telephone use)
Home supports (family, friends, CCAC)
Safety (falls, fires, wandering, meds,
driving, violence, etc.)
Initial Assessment
Mental Status Exam
Use standardized simple instrument
(e.g. Folstein’s MMSE*)

MMSE cut-off < 24/30 has 75-85%
sensitivity, 70-80% specificity
Clock-drawing may improve sensitivity


Less reliable for limited English, extremes
of formal education
Make sure patient is not delirious
*J Psychiatr Res 1975; 12:189-98
Initial Assessment
Physical Exam
Malnutrition (Subjective Global Assessment Detsky et al.)
Focal neurologic deficits
Parkinsonian features (remember TRAP)
Forget “frontal release” signs (i.e. glabellar
tap, snout, pout, grasp, palmo-mental, etc.) not helpful in diagnosis
Back to the Case
Progressive difficulty with cooking,
aspects of self-care
Occasionally wandering, getting lost
Forgetting names of friends
MMSE 17/30
Probable dementia, typical features of
Alzheimer’s Disease
Question 3
What basic investigations should be
done to rule out reversible causes?
Reversible Causes
(3-5% of all dementias)
Hypothyroidism
Depression (“Pseudodementia”)
Subdural Haematoma
Drug-Induced (narcotics, sedatives, anticholinergics, etc)
B12 Deficiency
Alcoholic Dementia
Metabolic Encephalopathy (Ca, renal/liver failure)
Neurosyphilis
Normal Pressure Hydrocephalus
Brain Tumours
Seizures
Basic investigations
•
•
•
•
•
•
CBC
Lytes/Creatinine
TSH
Glucose
Calcium
B12 (recommended by AAN)
CMAJ 1999; 160(12 Suppl)
Optional Investigations
(In selected patients)
Serum B12 (if not done as matter of routine)
RBC Folate (e.g. alcoholic)
VDRL
HIV
SPECT/PET perfusion scanning (research)
EEG
Evoked Potentials
Genetic testing for AD or other not currently
recommended
*CMAJ 1999; 160(12 Suppl)
Irreversible Causes
Alzheimer’s Disease (60-70%)
Cortical Lewy Body Disease (assoc with PD) (1025%)
Vascular (Multi-infarct) Dementia (10-20%)
Fronto-Temporal Dementia (5%)
Mixed Dementia (10-25%)
Miscellaneous (e.g. PSNP)
Question 4
Should she have neuroimaging (CT
scan or MRI)?
Criteria for Neuroimaging
Age <60
Rapid decline in mental or physical function (over 3-6
mo.) or short duration of dementia (<2 y.)
New localizing neurologic sign
Recent head trauma or unexplained neurologic
symptoms (e.g. headache, seizures)
History of any cancer
Anticoagulants or bleeding disorder
History of incontinence or early gait disorder
Gait disturbance
Unusual/atypical presentation
CMAJ 1999; 160(12 Suppl)
Neuroimaging
Useful in changing diagnosis and/or
management of 5-10% of patients
Contrast-enhanced CT improves yield for
strokes and tumours by 10-15%
Unclear if MRI (cost ~ $850-1000) superior to
CT (~$250-350)
SPECT/PET useful in academic settings but
not recommended routinely
AAN now recommends non-contrast CT or
MRI in initial evaluation of all patients
Neurology 2001; 56:1143
Question 4
Should she have neuroimaging (CT
scan or MRI)?
Answer:
• CT head not indicated
Typical features of dementia
No focal neurological deficits
No high risk features
Question 5
Is there any treatment available?
Classes of Therapy
Cognitive-enhancing drug therapy

Mainly acetylcholinesterase inhibitors
Symptomatic management of behavioural
disturbance e.g. neuroleptics, SSRIs
Potentially disease modifying agents

Memantine, Vit E & Selegilene, Estrogen
replacement, NSAIDs (more prophylaxis)
Future directions (very interesting/exciting)

Secretase modulators, immunization, chelators
Cognitive-Enhancing Drug
Therapy
Acetylcholinesterase Inhibitors




Tacrine (Cognex - hepatotoxic)
Donepezil (Aricept)
Rivastigmine (Exelon)
Galantamine (Reminyl)
Acetylcholinesterase Inhibitors
Has best current evidence of efficacy
Increases acetylcholine levels (major
depleted neurotransmitter in Alzheimer’s
disease)
May have role in other dementias (esp. Lewy
Body Dementia, mixed dementia) – no real
evidence
Most evidence/experience with Donepezil
(Aricept)
Donepezil (Aricept)
Once daily dose
Well tolerated (7-16% discontinuation rate,
only significant s/e are cholinergic – N + V,
Dx, but no serious side effects)
3-6 month trial to determine benefit
Cannot predict who will benefit
Currently covered by ODB under limited use
criteria ($5/day otherwise)
Donepezil (Aricept)
(Rule of thirds)
20-35% major benefit (reversal of cognitive
deterioration by 6-12 months)
30-40% minor benefit (stabilization of
progression)
25-40% no benefit
The AD2000 study, the only non-drug
company sponsored study, found no benefit
in terms of disability progression or entry into
institutional care
Question 5
Is there any treatment available?
Answer:
Options discussed
Started on Donepezil 5 mg OD
To be reassessed in 3 months
When to Refer?
Depending on comfort level of Internist:
Atypical symptoms/unusual features
Rapid progression
Behavioural disturbances
Initiation/monitoring of treatment
Associated possible depression
Caregiver burnout/stress
Ethical issues – for discussion
Disclosure of diagnosis
Driving – obligation to report in Ontario
Caregiver burden
Institutionalization
Advanced directives
Cultural relevance (and sensitivity on the part of the
physician)
Depression (diagnosis and treatment

Watch for anticholinergic SE’s from antidepressants – may
worsen dementia symptoms
Behavioural disturbances and their treatment