It's very hard, indeed. 

Known reasons for cholesterol changes can vary among
- change in exercise/activity routine 
- dietary changes 
- stress/sleep habits
- alcohol consumption 
- genetics 
- ....

So, unless the study accounts for these, seems like cholesterol change might just be at best an indirect marker of potential risk to develop dementia.



south_korea_ln

A limitation of the study is that while people who started or stopped taking cholesterol drugs were not included in the study to eliminate the medication-induced fluctuations in cholesterol, researchers did not have information on any changes in dosage or people who did not take their medication as prescribed, which could affect cholesterol changes.

This makes me curious about potential causes for cholesterol fluctuations. Presuming this isn't causal, what is?

science

Fluctuating Cholesterol Levels Linked to 60% Higher Dementia Risk

Control is hard:

> A limitation of the study is that while people who started or stopped taking cholesterol drugs were not included in the study to eliminate the medication-induced fluctuations in cholesterol, researchers did not have information on any changes in dosage or people who did not take their medication as prescribed, which could affect cholesterol changes.

This makes me curious about potential causes for cholesterol fluctuations. Presuming this isn't causal, what is?