I think it's extremely likely it's caused by something either unknown or previously considered to be safe for humans. Would be nice to study groups of people and see their rates of this illness. Multi-group elimination diet, with HTMA and blood and bone marrow tested for presence of metals, oxidants, etc.

I'd like to assume epidemiologists are all over this?

I think the main problem is that there's no money in saving old people. The current system we have is built around what can benefit the pharmaceutical industry the most, on a long-term basis. Old folks die too soon and often don't have much money to begin with, so sadly it's likely not high on the priority list.