What causes Alzheimer's?
We still don't fully understand what causes Alzheimer's disease, but scientists are zeroing in on the answers. This is one of the most exciting - and most important - areas of research, because understanding the causes should lead to more targeted treatments and ways to prevent the disease.
Scientists generally agree that there is unlikely to be a single clear "cause" of Alzheimer's. It is more likely the result of a combination of inter-related factors, including genetic factors, which are passed along family lines of inheritance, and environmental influences, which range from previous head trauma to educational level to one's experiences early in life. Each of these "risk factors" is currently the subject of a great deal of research. A growing body of research is also helping to identify various "lifestyle factors," such as dietary habits, high blood pressure and high cholesterol, which may influence one's risk of Alzheimer's disease.
What is clear is that Alzheimer's develops as a result of a complex cascade of biological processes that take place over many years inside the brain.
Stunning progress has been made recently in unraveling this cascade, and scientists now have a much clearer picture of what happens to the brain when Alzheimer's strikes.
What is known about risk factors for Alzheimer's?
The answers to this central question are evolving as research provides more information. Right now, age is the primary risk factor for Alzheimer's, along with family history (discussed under genetics). More women than men have Alzheimer's, but this is likely because women generally live longer than men; the incidence by age is similar among men and women. Education level and previous history of head trauma are also generally agreed upon as probable risk factors for Alzheimer's. The use of certain groups of drugs, including non-steroidal anti-inflammatory drugs (NSAIDs) and cholesterol-lowering drugs called statins, may also impact Alzheimer's risk, according to a number of studies. Compelling new evidence is now indicating that other "lifestyle factors," such as one's dietary habits, high blood pressure and high cholesterol, may impact one's risk for developing Alzheimer's disease. The reasons why these factors increase Alzheimer's risk are unclear, but there are clues.