Dementia is known to cause a major change in the way that a person retains memory, thinks, and behaves. This may affect the way that people do decision making and do other things. The leading cause of Dementia is Alzheimer’s disease. Aside from this, these are the other possible causes of dementia: long-time alcohol and drug use can be one of the reasons why people develop this condition.
This can occur even when people are still young. It would depend on how often and how long they have used drugs or alcohol. Some may also develop it because of infections of the central nervous system. Hydrocephalus may also be a cause of dementia, but this may occur because of other medical conditions.