Notwithstanding many technological advances, there is still no fool-proof method for diagnosing Alzheimer’s disease, (avoiding the fact that the brain changes occur decades before symptoms).  There is no blood test or imaging technique that is definitive.  Even autopsy diagnosis has its problems.  Diagnosis of Alzheimer’s disease remains a clinical diagnosis based on history, symptoms, patterns, and clinical judgment.

 The criteria for a diagnosis of possible Alzheimer’s disease:

  • The afflicted individual must be demented – disabled by the decline.
  • Symptoms appear gradually over months to years
  • There is progressive worsening of cognition
  • The initial and cardinal deficit is short-term memory (i.e., new learning)
  • Less commonly language deficits (e.g., word-finding) appear early
  • There are deficits in other skills such as planning, reasoning, judgment, sequencing

The diagnosis of possible Alzheimer’s disease:

  • There is sudden onset of symptoms
  • Progression is not gradual
  • There is concomitant cerebrovascular disease
  • Clinical features of Lewy body disease
  • There are other medical (e.g., thyroid disease, cancer) or neurologic diseases (e.g., head injury, stroke) present that may impair mental functions
  • There are medications or drugs present that may impair cognition

Mild Cognitive Impairment is diagnosed when:

  • Cognitive decline noted by self or informant or clinician
  • Objective evidence of cognitive decline – most typically in short-term memory
  •  Independence is not compromised

Neuroimaging/biomarkers:

  • CT or MRI based images are prudent to rule out pathology such as cerebrovascular disease or tumors that would modify clinical management
  • Amyloid tests in isolation cannot reliably diagnose Alzheimer’s disease or Mild Cognitive Impairment
  • Measuring CSF and/or blood levels of amyloid or tau proteins are not clinically useful at this time.

Persons with rapid onset (onset within one year) cognitive decline should be referred to specialists who have experience and diagnostic capabilities to evaluate and manage these conditions.

Pharmacological treatment:

  • Cholinesterase inhibitors (CHIs) include Aricept (donepezil), Exelon (rivastigmine), and Razadyne (galantamine)
  • CHIs are recommended for treatment of Alzheimer’s disease or Alzheimer’s disease with a cerebrovascular component
  • CHIs are recommended for treatment of dementia associated with Parkinson’s or Lewy body disease
  • The findings for effectiveness of CHIs for treating vascular dementia is inconsistent
  • Evidence of effectiveness of CHIs indicate that they are comparable and selection should be made based on clinical criteria such as tolerability and ease of use
  • The combination of CHIs and Namenda (memantine), although rational and safe, lacks empirical support for increased efficacy
  • CHI use may increase risk of gastrointestinal bleeding, tachycardia, or heart block; worsen asthma or other pulmonary disease; cause urinary obstruction; increase risk of seizures, or prolong actions of muscle relaxants
  • There is no clear evidence for efficacy of CHIs in neuropsychiatric disease
  • Discontinuation of CHIs should be based on side effects, drug costs, or dementia progressing to end stage (stage 7).