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  • Alzheimer’s dementia

  • 331.0 Alzheimer’s disease

  • G30.9 Alzheimer’s disease, unspecified


  • A degenerative neurologic disorder characterized by progressive dementia
  • Results in inability to care for oneself or interact in the environment

Essentials of Diagnosis

  • Insidious onset
  • Gradual development of forgetfulness that degenerates into other failures of cerebral function
  • Concise pathology that accounts for 50% of all dementia cases2

General Considerations

  • Definitive diagnosis is made upon autopsy
  • Imaging in late stages of the disease reveals hippocampal and frontal lobe atrophy
  • Early in the disease process, all other possible causes of dementia are ruled out in order to diagnose Alzheimer’s disease


  • Onset primarily occurs at age 60 years and older
  • Women 3 times more likely than men
  • Weak genetic link; most commonly idiopathic

Signs and Symptoms

  • Loss of cognitive function, most commonly in the following sequence
    • Abstract thinking
    • Judgment and problem-solving
    • Language for communication
    • Personality changes
  • Eventually the person loses ability to perform self-care or ADLs
  • Although the ability to perform automatic movements is maintained, the understanding of purpose behind the activities is lost
  • As the person loses this understanding, he/she may participate in less physical activity, resulting in disuse atrophy

Functional Implications

  • Loss of
    • Interaction in the environment
    • Memory and goal-directed behavior
    • Independence with ADLs
    • Strength and mobility

Possible Contributing Causes

  • Unknown, primarily idiopathic

Differential Diagnosis

  • Stroke (multi-infarct dementia)
  • Tumor
  • Subdural hematoma
  • Hydrocephalus
  • Dementia of AIDS
  • Paraneoplastic limbic encephalitis
  • Nutritional deficiencies
  • Metabolic disorders
  • Pseudodementia of depression
  • Supranuclear palsy
  • Lewy-body disease
  • Age-related dementia

Laboratory Tests

  • CSF for protein analysis
  • Neuropsychologic testing


  • CT of the Brain
  • MRI of the Brain
  • SPECT for hypoperfusion in the parietal and temporal regions
  • PET scan for abnormal brain proteins

Diagnostic Procedures

  • EEG for brain function

  • In advanced stages of Alzheimer’s disease, MRI will show frontal lobe atrophy
  • In early stages, EEG may show resting alpha frequency declines
  • Most imaging and tests are designed to rule out other causes of the apparent dementia


  • Aricept

  • To neurologist for imaging, disease management, medication
  • To social worker for family support and coordination of care
  • For occupational therapy (home management and ADLs)
  • To hospice for end-of-life care

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