Experimental Factor Ontology identifier EFO_1001870 (late-onset Alzheimers disease) can be described as follows. This is the most common form of the disease, which happens to people age 65 and older. It may or may not run in families. So far, researchers haven’t found a particular gene that causes it. No one knows for sure why some people get it and others don’t. Also known as: Alzheimer Senile Dementia, Alzheimer Type Senile Dementia, Senile Dementia, Alzheimer Type, late-onset Alzheimer's.