Late-onset/sporadic Alzheimer's disease is a polygenic and heterogeneous disease influenced by lifestyle factors.

“then you compare that to what we in this paper called age-related dementia Which is far more common than what people have much you know you know 95 plus percent of cases of Alzheimer's disease and what people um might call late onset Alzheimer's disease if there's a genetic component it's polygenic very um you know imperfectly penetrant for a number of reasons that we can talk about very heterogeneous disease course Very heterogeneous uh pathology if we actually look at the brains and see what's going on in there it looks very different from person to person”