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Home › Research › What the research found › Every row

Every row of the evidence table

One row per finding: what was tested, which way the result went, and how the study was built. The answer by area, and where the studies disagree, are on the main page.

Every row

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Area All 382 Care, carers and services 140 Medicines 85 Genes (not modifiable) 35 All modifiable factors together 27 Diet and supplements 23 Exercise and activity 21 Sleep, mood and social life 19 Hearing and vision 8 Alcohol, tobacco and cannabis 6 Infection and vaccination 5 Heart and metabolic health 4 Injury, delirium and falls 4 Environment 3 Cognitive activity 2
Question Both Prevention 190 Treatment 192
Direction Any Benefit 144 Harm 105 No effect 38 Mixed 37 No direction reported 58
Design Any meta-analysis 57 randomised trial 44 phase 3 trial 15 systematic review 9 phase 2 trial 10 cohort study 136 phase 1 trial 2 cross-sectional study 31 case-control study 14 modelling study 20 regulatory decision 7 company announcement 1 coverage determination 1 None 35
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Showing 3 of 382 rows. One row per study per exposure: a study that tested two different things appears twice, once for each.

Scroll the table sideways to see every column.

Research and outcomes, 3 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 Harm
why

Direction is for the APOE4 allele, whose effect ranged from OR 2.22 in Caribbean-Hispanic to 6.13 in Peruvian/Bolivian participants. The APOE2 allele went the other way (OR 0.81). Not modifiable.

 Alzheimer's disease and related dementias (odds ratio) case-control study 12,221 APOE ε4 meta-analytic OR 2.32 (95% CI 2.09-2.57); range 2.22 (Caribbean-Hispanics) to 6.13 (Peruvians/Bolivians) Alzheimer's & Dementia 2025
✓ Peer-reviewed PMID 40219824
APOE genotype Genes (not modifiable) Prevention Harm
why

Direction is for carrying APOE*4: the ε3/ε4 odds ratio fell stepwise from 4.54 in East Asian to 3.46 in White, 2.18 in Black and 1.90 in Hispanic individuals; ε2 was protective in White and Black but not Hispanic or East Asian individuals. Not modifiable.

 Odds of Alzheimer's disease by APOE genotype, across ancestry, sex and age case-control study 68,756 Odds ratios for APOE*34 and AD risk attenuated following East Asian (OR, 4.54; 95% CI, 3.99-5.17),White (OR, 3.46; 95% CI, 3.27-3.65), Black (OR, 2.18; 95% CI, 1.90-2.49) and Hispanic (OR, 1.90; 95% CI, 1.65-2.18) individuals. Similarly, ORs for APOE*22+23 and AD risk attenuated following White (OR, 0.53, 95% CI, 0.48-0.58), Black (OR, 0.69, 95% CI, 0.57-0.84), and Hispanic (OR, 0.89; 95% CI, 0.72-1.10) individuals JAMA Neurology 2023
✓ Peer-reviewed PMID 37930705
Rare protective or risk variant (APOE3 Christchurch, APOE R145C, RELN, FN1) Genes (not modifiable) Prevention Harm
why

Direction is for carrying the African ancestry-specific APOE R145C variant with an ε3/ε4 genotype: three-fold higher odds of AD and onset about six years earlier in the discovery stage, replicated in stage 2 and concordant in stage 3. Not modifiable.

 Alzheimer's disease case status and age at onset among APOE ε3/ε4 carriers of African ancestry case-control study 31,929 R145C was associated with an increased risk of AD (odds ratio [OR], 3.01; 95% CI, 1.87-4.85; P = 6.0 × 10-6) and was associated with a reported younger age at AD onset (β, -5.87 years; 95% CI, -8.35 to -3.4 years; P = 3.4 × 10-6) JAMA 2023
✓ Peer-reviewed PMID 36809323

How this table was built, and where it is weak →