Alzheimer's appears be influenced by a combination of genetic, environmental, and other factors. Some major factors that appear to increase the risk of Alzheimer's disease include:
Age. Alzheimer's disease is most common in people older than age 65.
Family history. Having a parent or sibling with the disease slightly increases risk.
Genetic mutations. Three genetic mutations are known to cause early-onset Alzheimer's, while a form of the APOE gene increases risk of late-onset disease.
Gender. Women are more likely than men to develop Alzheimer's disease.
Other conditions. The same factors that raise the risk of heart disease, such as high blood pressure, high cholesterol, and diabetes, also increase Alzheimer's risk.
Education. Research shows a link between lower education levels and higher risk of Alzheimer's disease.
Head injury. Some studies show a link between traumatic head injuries and Alzheimer's risk.