Genetic Factors of Alzheimer's Disease Modulate How Diet is Associated with Long-Term Cognitive Trajectories: A UK Biobank Study.
Level 3 - non-randomized controlled study
Prospective longitudinal observational cohort study
PubMed 33252089 · doi:10.3233/JAD-201058
What was done
Researchers modeled 10-year fluid intelligence (FI) trajectories and regressed them onto self-reported diet in 1,787 mid- to late-aged adult UK Biobank participants. Diet was measured using a Food Frequency Questionnaire (FFQ) covering 49 whole foods. Analyses were stratified by genetic and familial risk for Alzheimer's disease (AD): family history (FH+ vs FH-) and APOE4 status (ɛ4+ vs ɛ4-).
What was found
- Daily cheese intake predicted higher FI scores over time across groups: FH- (β = 0.207, p < 0.001), ɛ4- (β = 0.073, p = 0.008), and ɛ4+ (β = 0.162, p = 0.001). - Daily alcohol of any type was positively associated with FI scores in the ɛ4+ group (β = 0.101, p = 0.022), and red wine intake was positively associated in FH+ (β = 0.100, p = 0.014) and ɛ4- (β = 0.59, p = 0.039). - Weekly lamb consumption was associated with improved FI trajectories in FH- (β = 0.066, p = 0.008) and ɛ4+ (β = 0.097, p = 0.044). - Added salt intake was associated with worse cognitive trajectories specifically among at-risk groups: FH+ (β = -0.114, p = 0.004) and ɛ4+ (β = -0.121, p = 0.009).
Why it matters
This study suggests that associations between specific dietary components and cognitive decline over a decade may differ based on individual genetic and familial risk for Alzheimer's disease.
Limits
The study is observational and cannot demonstrate causality. Dietary intake was self-reported via a 49-item FFQ, which is prone to recall bias and misclassification. Residual confounding by socioeconomic status, overall lifestyle, and baseline health could explain the observed associations.
Cited by
- supports A recent study found that greater consumption of unprocessed red meat was associated with improved outcomes in people carrying APOE4 single nucleotide polymorphisms.