What are the risk factors?

  • Age. Alzheimer's usually affects people older than 65, but can rarely, affect those younger than 40.  The average age at diagnosis is about 80.  Less than 5 percent of people between 65 and 74 have Alzheimer's.  For people 85 and older, that number jumps to nearly 50 percent.
  • Heredity.  Your risk of developing Alzheimer's appears to be slightly higher if a first-degree relative -parent, sister or brother - has the disease.
  • Sex.  Women are more likely than men are to develop the disease, in part because they leave longer.
  • Lifestyle.  The same factors that put you at risk of heart diseases, such as high blood pressure and high cholesterol, may also increase the likelihood that you'll develop Alzheimer's disease.  And, keeping your body fit isn't your only concern - you've got to exercise your mind as well.
  • Head injury.  The observation that some ex-boxers eventually develop dementia leads to the question of whether serious traumatic injury to the head (for example, with a prolonged loss of consciousness) may be a risk factor for Alzheimer's.