What causes Alzheimers Disease (AD)?
Scientists don’t yet fully understand what causes AD, but it is clear that it develops because of a complex series of events that take place in the brain over a long period of time. It is likely that the causes include genetic, environmental, and lifestyle factors. Because people differ in their genetic make-up and lifestyle, the importance of these factors for preventing or delaying AD differs from person to person. Genetics play a role in some people with AD. A rare type of AD, called early-onset AD, affects people ages 30 to 60. Some cases of early-onset AD, called familial AD, are inherited. Familial AD is caused by mutations (permanent changes) in three genes. Offspring in the same generation have a 50-50 chance of developing familial AD if one of their parents had it. Most cases of AD are late-onset AD, which develops after age 60. Although a specific gene has not been identified as the cause of late-onset AD, genetic factors do appear to increase a person’s risk of developing th
