Cognitive

Dementia

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Dementia, Alzheimer's Disease, Alzheimer Disease, Alzheimers Disease

  • Definition
  1. Chronic loss of previously acquired mental function
  • Epidemiology
  1. Prevalence
    1. Age over 65 years: 10%
    2. Age over 90 years: 37-50%
  • Causes
  • Risks Factors
  • Alzheimer's Disease
  1. Age >65 years old (greatest risk factor)
  2. Apo E4 Allele
    1. Confers 8% risk if two Alleles
  3. Family History of Alzheimer's Disease
  4. FAD gene
  5. Female gender
  6. Low education
  7. Head Trauma
  8. Cardiovascular disease (e.g. prior Myocardial Infarction)
  9. Cerebrovascular Disease (e.g. prior Cerebrovascular Accident)
  10. Diabetes Mellitus
  11. Combined CV factors in middle age (Odds Ratio 3.5)
    1. Hyperlipidemia
    2. Hypertension (increased systolic Blood Pressure)
    3. Kivipelto (2001) BMJ 322:1447-51 [PubMed]
  • Types
  • Presentations
  1. Cortical (e.g. Alzheimer's Disease): 60-70% of cases
    1. Short Term Memory loss
    2. Aphasia
    3. Apraxia
  2. Subcortical (e.g. Vascular Dementia): 10-20%
    1. Mental slowing
    2. Mood disturbance
  3. Metabolic Dementia (e.g. Vitamin B12 Deficiency)
    1. Similar presentation as subcortical Dementia
  4. Lewy Body Disease (7%)
    1. Parkinsonian symptoms with Dementia
  5. Frontotemporal Dementia
    1. Socially inappropriate and compulsive behaviors
    2. Empathy loss, change in political and religious beliefs
    3. Progressive Aphasia
  6. Mixed Dementia (10-20%)
    1. Combined Cortical and subcortical
    2. Usually Alzheimer's with Multi-infarct Dementia
  • Types
  • Dementia Syndromes
  1. Alzheimer's Disease (60-70%)
  2. Dementia with Lewy Bodies (15-25%)
  3. Frontotemporal Dementia (5-15% overall, but 60% in those 45-60 years old)
  4. Vascular Dementia (5-20%)
  5. Creutzfeldt-Jakaob Disease (<1%)
  • Criteria
  1. Insidious, gradual onset (months) of deterioration
    1. Mild to severe fluctuations
    2. All higher cortical functions
  2. Long duration of symptoms
  3. Normal Level of Consciousness, but altered content
    1. Impaired memory and
    2. One higher cortical function (e.g. Judgement)
  4. Vital Signs typically normal
  • Presentations
  • Early
  1. New information is difficult to learn and retain
  2. Complex tasks are difficult to perform
  3. Unable to solve simple problems
  4. Getting lost in familiar surroundings
  5. Difficulty expressing oneself
  6. Irritable or aggressive behavior
  • History
  1. Family members should accompany patient to appointment, sitting side-by side with patient
  2. First ask questions of patient "why are you here?"
    1. Do not spend much time on this aspect
    2. Establish relationship with patient and establish reliability as historian
  3. Ask family (and patient if mild Dementia)
    1. Baseline functional status (education level, work responsibilities)?
    2. When was the first time their thinking and memory was completely normal?
    3. Timeline of cognitive function loss since onset?
    4. Is there any time you thought they were having a stroke?
    5. Do they repeat? misplace? Forget names? Rely more on notes and calendars?
    6. Who is in charge of medications? Bill Paying? checkbook balancing (IADLs) ?
    7. Word finding difficulty?
    8. Get lost driving?
    9. Do you feel comfortable leaving them alone? Overnight? For a weekend? for a week?
    10. Can they perform Activities of Daily Living (ADLs)?
    11. Are they depressed? anxious? agitated or restless?
    12. Do they have Hallucinations?
    13. How is sleep? Do you sleep in the same bed? Nighttime Incontinence?
    14. Has there been Head Trauma?
  4. References
    1. McCarten (2009) UMN CME Internal Medicine Review, Minneapolis
  • Findings
  • Signs and symptoms
  1. Normal alertness, awareness, attentiveness
  2. No Hallucinations or Delusions
  3. Disorientation
  4. Memory Impairment (short much more than long term)
    1. New forgetfulness
    2. Difficult word finding
  5. Impaired Executive, Social, or cognitive function
    1. Driving difficulties or getting lost
    2. Neglect of self care and household chores
    3. Difficult money handling
    4. Work mistakes
    5. Judgement and Language impaired
  6. Behavior changes
    1. See Behavior Problems in Dementia
  7. Personality change
    1. Inappropriately friendly or even flirtatious
    2. Affect shallow or blunted or social withdrwal
    3. Frustration to explosive spells
  8. Psychiatric symptoms
    1. Suspiciousness or paranoia
    2. Withdrawal or apathy
    3. Abnormal beliefs or Hallucinations
  9. Provocative Factors
    1. Acute illness
    2. Hospitalization
    3. Minor surgery
    4. Bereavement
  • Evaluation
  • Dementia Screening Tools
  1. See Mental Status Consolidated Screening
  2. Mini-Cognitive Assessment Instrument
    1. Patient repeats and recalls 3 unrelated words, and draws a clock face with a given time
  3. General Practitioner Assessment of Cognition (GPCOG)
    1. https://www.alz.org/documents_custom/gpcog(english).pdf
  4. Ascertain Dementia 8-Item Informant Questionnaire
    1. https://www.alz.org/documents_custom/ad8.pdf
  1. See Mental Status Exam (lists all tests, history, exam)
  2. St. Louis University Mental Status (SLUMS)
    1. http://medschool.slu.edu/agingsuccessfully/pdfsurveys/slumsexam_05.pdf
  3. Addenbrooke's Cognitive Examination (ACE)
    1. Differentiates Alzheimer's from other Dementias
    2. Detect early Dementia
  4. Mini-Mental Status Exam (requires payment for use)
    1. Standard decline 3 points per 6 months
    2. Error is +/- 3 points
  5. Montreal Cognitive Assessment
    1. http://dementia.ie/images/uploads/site-images/MoCA-Test-English_7_1.pdf
  6. Psychometric Testing
    1. Test of higher cognitive functioning
      1. Logical, abstract, conceptual and verbal reasoning
      2. Identifies more subtle changes in cognition
    2. Indications
      1. Early Dementia
      2. Depression
      3. Alcohol Abuse versus Alzheimer's Disease
      4. Unusual Dementias
      5. Non-english speaker or patient with less education
  • Diagnosis
  • Associated Conditions
  1. Gait Apraxia
  2. Disinhibited behavior
  3. Slurred speech if Vascular
  4. Anxiety, mood, and sleep disturbance
  5. Delusions and Visual Hallucinations
  6. Speech rambling, irrelevant, and incoherent
  7. Personality change
  • Labs
  1. Goals: Rule out reversible cause (Delirium Causes)
  2. Guidelines vary based on organization
    1. American Academy of Neurology (AAN)
    2. Canadian Consensus Conference on Dementia (CCCD)
  3. Standard Evaluation
    1. Thyroid Stimulating Hormone (AAN, CCCD)
    2. Serum Vitamin B12 Level (AAN)
    3. Complete Blood Count (CCCD)
    4. Comprehensive Metabolic Panel
      1. Serum Electrolytes
      2. Serum Calcium
      3. Serum Glucose
      4. Liver Function Tests
      5. Renal Function Tests
  4. Evaluation only as indicated
    1. Syphilis Serology (VDRL or RPR)
    2. Urinalysis
    3. Serum Magnesium
    4. Arterial Blood Gas (ABG) or Venous Blood Gas (VBG)
    5. Medication Levels
    6. Chest XRay
    7. Electrocardiogram (EKG)
    8. Electroencephalogram (EEG)
      1. Seizure disorder
      2. Creutzfeldt-Jakob Disease (or other prion disease)
    9. Lyme Titer
    10. Lumbar Puncture for rapidly progressive Dementia
      1. Systemic signs and symptoms
      2. Atypical presentation
      3. Cancer
      4. Hydrocephalus
      5. Infectious disease
        1. Neurosyphilis
        2. HIV Infection
        3. Cerebral Lyme Disease
        4. Creutzfeldt-Jakob Disease (or prion disease)
          1. Positive CSF for 14-3-3 protein
    11. Heavy metal screening
    12. Ceruplasmin for Wilson' Disease
    13. Arylsulfatase for metachromatic leukodystrophy
    14. Serum Protein Electrophoresis for Multiple Myeloma
    15. Human Immunodeficiency Virus (HIV)
    16. Connective Tissue Disease
      1. Erythrocyte Sedimentation Rate (ESR)
      2. C-Reactive Protein (C-RP)
      3. Antinuclear Antibody (ANA)
      4. C3 Complement
      5. C4 Complement
      6. Anti-DS DNA
    17. Urine Toxicologic screen
    18. Urine porphobilinogens
    19. Apolipoprotein E (not recommended)
  • Imaging
  1. Imaging modalities
    1. Brain MRI (preferred): Especially coronal views
      1. Hippocampal atrophy is hallmark
    2. CT Head
    3. Positron Emission Tomography (PET)
      1. Indicated if definitive diagnosis will impact management
  2. Imaging Indications (indicated in most cases of Dementia)
    1. Age under 60 years old
    2. Dementia with duration under 1 month
    3. Rapid progression over months
    4. Recent Head Trauma
    5. History of Cerebrovascular Accidents
    6. History of cancer
    7. History of Anticoagulant use
    8. Seizure disorder
    9. Urinary Incontinence of new onset
    10. Headaches
    11. Focal neurologic findings
    12. Visual field defects
    13. Papilledema
    14. Gait Abnormality or Ataxia
  3. References
    1. Chertkow (2001) Can J Neurol Sci 28:S28-41 [PubMed]
    2. Dietch (1983) West J Med 138:835 [PubMed]
  • Diagnostics
  • Special Tests (Research use only currently)
  1. Cerebrospinal Fluid for Alzheimer's specific proteins
    1. High tau
    2. Low Beta-Amyloid
  2. Functional imaging
    1. SPECT scan
    2. Positron Emission Tomography (PET Scan)
    3. Functional Head MRI
  • Differential Diagnosis
  • Course
  1. Cases due to reversible cause: 10-20%
  2. High index of suspicion for reversibility in elderly
  • Management
  1. Rapidly progressive Dementia (weeks to months)
  2. Dementia in a young patient
  3. Severe behavior psychiatric abnormalities
  4. Red Flags for uncommon Dementia
    1. Significant personality change
    2. Extrapyramidal signs
    3. Rapid progression
    4. Gaze Palsy
    5. Urinary Incontinence
    6. Gait Abnormality
  • Management
  • Evaluate the Caregivers - Family journey phases
  1. Prediagnostic: Is there a real issue?
  2. Diagnosis: Tramua of the diagnosis
  3. Role changes: Taking away rights
  4. Chronic caregiving: Engulfment and exhaustion
  5. Shared care: Obtaining respites
  6. Long term care: Patient is moved to long-term care
  7. End of life: Prolonging life versus a good death
  8. Reference
    1. Caron (2000) Alzheimer's Disease - The Family Journey, North Ridge Press, Plymouth, MN
  • Resources