• Most common cause of dementia
  • Progress, neurodegenerative disorder of unknown cause that commonly first manifests as impairment in memory
  • As the disease progress the patient becomes more disoriented, has increased difficulty communicating and performing activities of daily living
  • Treatment options are limited though Memantine (Namenda) and a class of drugs known as acetylcholinesterase inhibitors [like Tacrine (Cognex)] have demonstrated some cognitive benefits


Symptoms and Signs

  • Initially: Loss of recent memory, often noticed only by close family members
  • As the disease progresses the patient becomes increasingly disoriented to both when and where they are.
  • Depression and other psychiatric symptoms are common
  • Late: Patients often develop difficulty effectively communicating, naming objects, and making simple calculation often causing them to leave work and give up family financial responsibilities.
  • A total cessation of speach, incontinence, and a bedridden state point to terminal manifestations of the disease



  • Sporadic with about 5% of cases associated with a familial cause (Familial Alzheimer disease- secondary to a mutated amyloid precursor protein on Chr 21)
  • Increased risk in people with Down’s syndrome (aka trisomy 21)



  • A clinical diagnosis in that test often just exclude other, possibly treatable, causes of dementia
  • MRI demonstrates ex vacuo enlargement of the ventricles and atrophy of the cerebral cortex



  • Memantine
  • Tacrine
  • Donepezil
  • Rivastigmine
  • Galantamine
  • Medications are also used to treat the psychiatric manifestations of the disease



  • Death is normally seen within 5-10 years of the first symptoms often secondary to infections or inanition


Differential Diagnosis

  • Alcohol induced amnestic syndrome
  • Lewy body dementia
  • Vascular dementia
  • Creutzfeldt-Jakob disease