1. General Features
   1. Multiple and severe cognitive impairments without impairment in consciousness
   2. Can be progessive or static condition
   3. Usually permanent but may be reversible
   4. Usually seen in elderly
   5. If problems do not significantly affect daily life: Mild Cognitive Impairment
2. Diagnostic Criteria
   1. Significant memory impairment with one major cognitive disturbance
   2. Onset is gradual w/continuing decline
   3. Exclusion of othe rcauses of symptoms
3. Epidemiology
   1. DAT is most common type of dementia
   2. Onset usually after age 65
   3. Women affected more than men
4. Course
   1. Early Stages
      1. Anomia: memory deficits and word-finding problems
   2. Middle Stages
      1. Further decline in memory and language
      2. Agnosias: loss of knowledge
      3. Personality change and psychosis
      4. Visuospatial impairment
   3. End Stages
      1. Global cognitive impairment
      2. Motor Problems
      3. Often death from opportunistic respiratory diseases
5. Neuropathology
   1. Neuroanatomical
      1. Cortical atrophy
      2. Hippocampal atrophy
      3. Enlarged ventricles
   2. Neurochemical
      1. ACH production decreased due to loss of neurons in Nuclues Basalis of Meynert
         1. Topic
      2. Other neurotransmitters affected
   3. Neurofunctional
      1. Reducd metabolism in posterior parts of brain
   4. Histopathological
      1. Plaques: patches of disintegrated nerve cell parts
      2. Neurofibrillary Tangles: twisted clumps of nerve cells
      3. DAT diagnosed by these analyses
6. Genetics
   1. Early Onset
      1. ~30 years
      2. 10% of all DAT cases
      3. Severe and rapid progression of symptoms
      4. Strong genetic component; genes on chromosomes 1,14,21
      5. Only 1 copy of gene needed to develop early-onset DAT
   2. Late Onset
      1. ~60 years
      2. 90% of all DAT cases
      3. APOE4 gene identified as risk factor
         1. Involved in lipid metabolism
         2. Gene on chromosome 19
         3. 2 copies assoc. w/inc chances of late onset DAT
7. Treatment
   1. Drugs that decrease ACH
      1. Cognex, Aricept, Exelon, Reminyl
      2. Small but measurable improvement
   2. Drugs that block Glutamate
      1. Namenda: Shows efficacy w/severe DAT in trials
8. Interventions
   1. Pharmacological
      1. Neuroleptics for non-memory symptoms
   2. Psychosocial
      1. External mnemonics
      2. Safe Return Program
      3. Family Support for "Caregiver Syndrome"
9. Differentials
   1. Vascular Dementia
      1. Vascular disease w/stepwise progression
   2. Pick's Dementia
      1. "Frontal" signs
   3. Parkinson's Dementia
      1. Poor motor disorder
   4. Huntington's Dementia
      1. Poor motor disorder w/choreiform & athetoid movements
   5. Jacob-Creutzfeldt Dementia
      1. Rapid cognitive decline in just few months