Cholesterol links to dementia varied by genetic region
A human genetic analysis examined four blood fat traits and seven brain outcomes, finding that some links changed when researchers excluded one gene region.
Limit: Genetic overlap among lipid traits can bias estimates attributed to cholesterol
Edited by Boris Djordjevic · AgingResearch.News
In human genetic data, researchers used Mendelian randomization, a method that uses genetic differences to study links between traits and disease. They examined four blood fat traits from the Global Lipids Genetics Consortium and seven brain-related outcomes from FinnGen.
Higher genetically predicted total cholesterol was associated with Alzheimer’s disease and dementia. Higher genetically predicted high-density lipoprotein cholesterol was linked to a lower likelihood of a combined stroke outcome excluding subarachnoid hemorrhage, a type of bleeding around the brain. Estimates for Alzheimer’s disease, dementia and memory loss were sensitive to excluding variants near APOE, a gene involved in fat transport. The stroke estimate remained materially unchanged after that exclusion. An additional analysis supported shared genetic signals for some cholesterol–outcome pairs outside the APOE region.
Why it matters
For age-related brain disease, the results bear on whether links to blood fats reflect the same genetic influences across different outcomes.
Caveats
The analysis used genetic proxies rather than a treatment trial; it did not test whether changing cholesterol levels would change brain outcomes.
From the paper
- Limitation
First, MR requires instruments that are relevant to the exposure, independent of confounders, and free from pathways to the outcome outside the exposure.
Quoted word for word from the full text on mdpi.com.
The paper
Beijing University of Chinese Medicine
Genes, Sep 30, 2026, Open access
