It is actually and very unfortunately both. One of the researchers we are connected to has posited that increased amyloid build up decreases the effectiveness

It is actually and very unfortunately both. One of the researchers we are connected to has posited that increased amyloid build up decreases the effectiveness of the glymphatic system, which is why we see lower delta power in older adults which then further reduces the ability to remove build-up. It's a vicious cycle. We also see this with cortisol levels in under slept individuals and exacerbated in people with AD. In response to a lack of sleep, the body increases cortisol, that increase in cortisol introduces challenges in getting good sleep, which increases cortisol. For most of us, this isn't an issue as we get on top of our sleep within a fairly short period and sort this out, but in people with AD, there is a cortisol dysregulation, and potential a circadian issue as well. One hypothesis why the AD paper I linked to earlier had such a huge impact on AD sufferers was because PTAS has been shown to have a 15% decrease in early night cortisol levels. The cortisol levels were not checked in the AD subjects because it was a feasibility study, but I'll be speaking with the researchers next week, and hopefully that is the plan for the next stage research.