Genetically determined low income modifies Alzheimer's disease risk

Area of Science:

• Neuroscience
• Genetics
• Public Health

Background:

• Socioeconomic status (SES) is linked to Alzheimer's disease (AD) prevalence, but causal links are unclear.
• Investigating the causal relationship between income and AD risk is crucial for public health strategies.

Purpose of the Study:

• To determine if higher income causally reduces the risk of developing Alzheimer's disease (AD).
• Utilizing Mendelian randomization (MR) to assess the protective effect of income on AD.

Main Methods:

• Selected single-nucleotide polymorphisms (SNPs) strongly associated with household income from UK Biobank data (n=286,301).
• Harmonized selected SNPs with AD genome-wide meta-analysis data (71,880 cases, 383,378 controls).
• Employed MR analysis with multiple sensitivity analyses to evaluate potential biases.

Main Results:

• Nine SNPs robustly associated with household income were used in the MR analysis.
• Higher household income was causally associated with a significantly lower risk of AD (OR 0.78, 95% CI: 0.69-0.89, P<0.001).
• Sensitivity analyses indicated no significant evidence of heterogeneity or pleiotropy.

Conclusions:

• The study provides robust evidence, under MR assumptions, for a causal link between higher household income and reduced AD risk.
• Findings suggest that income may be a modifiable factor for AD prevention strategies.