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Every row

Showing 14 of 382 rows. One row per study per exposure: a study that tested two different things appears twice, once for each.

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Research and outcomes, 14 rows. Every row links to its source.
Exposure Question Direction Outcome measured Design People Effect size, as the source reported it Source
APOE genotype Genes (not modifiable) Prevention Mixed
why

Direction is for APOE genotype after 90: ε2 carriers had lower dementia risk, while the ε4 association was not statistically significant. Women and Black participants had higher risk than men and Asian participants. Age-standardised incidence was 116.82 per 1000 person-years.

Incident all-cause dementia after age 90 by APOE genotype, sex and race cohort study 805 The age-standardised incidence rate was 116·82 cases per 1000 person-years (95% CI 93·69-139·96). In Fine-Gray models, dementia risk was higher in female than in male participants (subdistribution hazard ratio [sHR] 1·89, 95% CI 1·30-2·76) and Black than Asian participants (sHR 1·75, 1·07-2·88), lower in APOE ε2 carriers than in non-carriers (sHR 0·39, 0·17-0·88), and not significantly higher in APOE ε4 carriers than in non-carriers (sHR 1·51, 0·92-2·47) The lancet. Healthy longevity 2026
✓ Peer-reviewed PMID 42551464
APOE genotype Genes (not modifiable) Prevention Harm
why

Direction is for carrying APOE ε4: 10-year dementia risk ratios of 1.59 (Filipino, confidence interval crossing 1) to 1.96 (Japanese), similar across the four groups despite carrier prevalence ranging from 14% to 25%. Not modifiable.

10-year dementia risk by APOE ε4 carriership in Chinese, Japanese, Filipino and non-Latino White adults cohort study 46,325 10-year risk ratios (95% confidence interval [CI]) ranged from 1.59 (0.66-3.10) among Filipino to 1.96 (1.36-2.78) among Japanese participants Alzheimer's & Dementia 2026
✓ Peer-reviewed PMID 42427166
APOE genotype Genes (not modifiable) Prevention Harm
why

Direction is for each additional ε4 allele: it did not change amyloid-related p-tau217 secretion, but for any given p-tau217 level tau spread faster across connected regions, and the p-tau217 threshold marking early tau-PET increases was 26-76% lower than in non-carriers.

Amyloid-associated plasma p-tau217 increase, and p-tau217-associated tau-PET spread, by APOE ε4 allele count cohort study 401 plasma ptau217 elevations were linked to faster tau-PET spread from local epicentres across connected brain regions in an ApoE4 allele dose-dependent manner, independent of amyloid [ADNI/A4-LEARN: mean standardized beta (β) = 0.44/0.56, P < 0.001/P < 0.001] ... (ADNI: 0/1/2 ApoE4 alleles = 0.62/0.34/0.15 pg/ml, representing ∼45% and ∼76% reductions from non-carriers; Fujirebio ptau217 assay; A4-LEARN: 0/1/2 ApoE4 alleles = 0.31/0.23/0.18 pg/ml, representing ∼26% and ∼42% reductions; Eli Lilly ptau217 assay) Brain 2026
✓ Peer-reviewed PMID 41410687
APOE genotype Genes (not modifiable) Prevention Harm
why

Direction is for APOE ε4 carriage, which strengthened the association between amyloid and plasma p-tau; plasma GFAP strengthened the p-tau-tau PET link mainly in non-carriers, and high GFAP went with faster longitudinal tau accumulation.

Strength of the amyloid-p-tau and p-tau-tau PET associations by APOE ε4 status and plasma GFAP, and longitudinal tau accumulation cohort study 806 stronger Aβ–pTau associations observed in APOE ε4 carriers (CPAS: β = 0.26, p = 0.003 for pTau231; ADNI: β = 0.45, p < 0.001 for pTau181) Molecular Neurodegeneration 2025
✓ Peer-reviewed PMID 41163175
APOE genotype Genes (not modifiable) Prevention Harm
why

Direction is for carrying two APOE4 copies: near-complete penetrance of Alzheimer's biology and earlier symptom onset.

Alzheimer's biomarkers and age at symptom onset cohort study 10,039 Nearly all APOE4 homozygotes showed Alzheimer's pathology by age 55 vs. about half of non-carriers Nature Medicine 2024
✓ Peer-reviewed PMID 38710950
APOE genotype Genes (not modifiable) Prevention Benefit
why

Direction is for carrying APOE2, which is associated with longer life irrespective of Alzheimer's status. The lifespan figures come from gene-targeted mice, not from the human cohort.

Lifespan / survival cohort study 24,661 Mice: "the median age at death was in the order of apoE2-TR (911 days) > apoE3 TR (825 days) > apoE4 TR (753 days) > Apoe KO (738 days)". In humans the abstract states only that "the association between APOE2 and longer lifespan persisted irrespective of AD status", without a numeric estimate. eLife 2020
✓ Peer-reviewed PMID 33074098
Polygenic risk / GWAS loci Genes (not modifiable) Prevention Harm
why

Direction is for midlife hypertension. Genetic risk for Alzheimer's did not modify it, which the authors read as everyone with hypertension standing to gain from treatment.

Incident dementia over 23-27 years cohort study 11,597 Midlife hypertension HR for dementia 1.19-1.34 across genetic risk tertiles (white participants); 1.31 (95% CI 1.04-1.66) in high-risk Black participants Neurology 2026
✓ Peer-reviewed PMID 42385118
Polygenic risk / GWAS loci Genes (not modifiable) Prevention Harm
why

Direction is for a higher polygenic score: each standard deviation raised AD odds 1.14-1.52-fold across European, African American, Caribbean Hispanic and Native American Hispanic groups (1.21-1.65 in replication cohorts), and the score tracked worse cognition, more AD neuropathology, smaller hippocampi and abnormal CSF biomarkers.

Association of an APOE-independent multi-ancestry polygenic risk score with AD, cognition, neuropathology, hippocampal volume and CSF biomarkers across ancestry groups cohort study not stated The PRS was significantly associated with AD in European ancestry, African American, Caribbean Hispanic and Native American Hispanic groups with adjusted odds ratios between 1.14 and 1.52 per PRS standard deviation. PRS performance was validated in the replication cohorts (odds ratios: 1.21-1.65) Nature genetics 2026
✓ Peer-reviewed PMID 42661068
Polygenic risk / GWAS loci Genes (not modifiable) Prevention Harm
why

Direction is for carrying the risk factors. Which factor mattered most differed by APOE risk group, on 2,065 cases split across 11 factors and three genetic strata, so the subgroup estimates are imprecise.

Incident all-cause dementia over 12.4 years cohort study 182,473 Low social contact HR 3.86 (95% CI 2.08-7.17) in low APOE risk group; less education PAF 11.35% in high APOE risk group Annals of Neurology 2025
✓ Peer-reviewed PMID 41085200
Polygenic risk / GWAS loci Genes (not modifiable) Prevention Harm
why

Direction is for a higher integrative polygenic score: dementia hazard rose 1.15-fold per SD in older community-dwelling people independently of APOE, generalising to Europeans, East Asians and memory-clinic patients, and reaching five-fold risk when combined with APOE ε4 in memory-clinic patients. Not modifiable.

Incident dementia by an integrative polygenic risk score (AD plus 23 vascular and neurodegenerative traits, excluding APOE) cohort study 241,935 iPRS-DEM was associated with dementia risk independently of APOE in the elderly (subdistribution hazard ratio [sHR]per1SD = 1.15, 95% confidence interval [CI]: 1.03 to 1.28), which generalized to Europeans (EUR-sHRper1SD = 1.28, 95% CI: 1.09 to 1.51]), East-Asians (EAS-sHRper1SD = 5.29, 95% CI: 1.43 to 34.36), and memory-clinic participants (sHRper1SD = 1.25, 95% CI: 1.11 to 1.42) Alzheimer's & Dementia 2025
✓ Peer-reviewed PMID 40042447
Polygenic risk / GWAS loci Genes (not modifiable) Prevention Harm
why

Direction is for a higher polygenic score: consistently associated with AD risk, age at onset and CSF biomarkers independently of APOE in Europeans and with AD risk in many other ancestries; a cross-ancestry score with the APOE region improved the association, and the signal weakened as the diagnosis was broadened.

Association of a European-derived AD polygenic score with AD risk, age at onset and CSF biomarkers across 17 European countries and populations of other ancestries cohort study not stated not established — pubmed abstract reports no numeric effect size. Nature genetics 2025
✓ Peer-reviewed PMID 40533518
Polygenic risk / GWAS loci Genes (not modifiable) Prevention Harm
why

Direction is for a higher polygenic risk score: each SD raised the dementia hazard 1.35- to 1.42-fold after adjustment including APOE ε4, and the new scores modestly improved prediction (AUC 74.7% to 75.7-76.1%) while still explaining less risk than APOE. Not modifiable.

Incident dementia (DSM-IV adjudicated) by polygenic risk score cohort study 12,031 PRS-83SNP, PRS-SBayesR, and PRS-CS were associated with incident dementia, with fully adjusted (including apolipoprotein E [APOE] ε4) hazard ratios per standard deviation (SD) of 1.35 (1.23-1.47), 1.37 (1.25-1.50), and 1.42 (1.30-1.56), respectively. The AUC of a model containing conventional/non-genetic factors and APOE was 74.7%. This was improved to 75.7% (p = 0.007), 76% (p = 0.004), and 76.1% (p = 0.003) with addition of PRS-83SNP, PRS-SBayesR, and PRS-CS, respectively Alzheimer's & Dementia 2023
✓ Peer-reviewed PMID 37177856
Rare protective or risk variant (APOE3 Christchurch, APOE R145C, RELN, FN1) Genes (not modifiable) Prevention Benefit
why

Direction is for one copy of the APOE3 Christchurch variant: median onset of cognitive impairment at 52 versus 47 years in matched PSEN1 E280A carriers without it, with preserved brain metabolism and fewer vascular amyloid features in the few imaged or autopsied. Not modifiable.

Age at onset of cognitive impairment in PSEN1 E280A carriers cohort study 1,077 the median age at the onset of cognitive impairment was 52 years (95% confidence interval [CI], 51 to 58), in contrast to a matched group of PSEN1 E280A carriers without the APOE3 Ch variant, among whom the median age at the onset was 47 years (95% CI, 47 to 49) New England Journal of Medicine 2024
✓ Peer-reviewed PMID 38899694
Rare protective or risk variant (APOE3 Christchurch, APOE R145C, RELN, FN1) Genes (not modifiable) Prevention No direction reported
why

Among 37 heterozygous carriers (ages 56.6-82.1) none had developed AD or MCI by the March 2022 data freeze and apolipoprotein B was lower than in non-carriers, but the authors say continued follow-up is necessary and no homozygotes were found, so protection could not be tested. No incidence comparison is reported, so no direction is recorded.

Alzheimer's disease or MCI diagnoses and blood lipid biomarkers in heterozygous APOE Christchurch carriers cohort study 455,306 not established — research letter with no pubmed abstract; the full text at pmc10685495 reports carrier counts and p-values (apob p = 0.004; p = 0.036… Molecular Neurodegeneration 2023
✓ Peer-reviewed PMID 38017580

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