It's hard to say right now. It might be one possibility if this line of research pans out.

This is a potential mechanism that they've experimentally built and triggered. There's no guarantee this happens in situ exactly as they've set up. There's also the chance that Alzheimer's is caused by various contributing factors.

This paper does look promising though, because they've triggered the disease from the liver using lipoproteins that have been observed.

I'd love for domain experts to weigh in.