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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 9 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, 9 rows. Every row links to its source.
Exposure Question Direction Outcome measured Design People Effect size, as the source reported it Source
Modifiable risk factors combined All modifiable factors together Prevention Harm
why

Direction is for carrying the risk factors: the Commission attributes 45% of cases to 14 modifiable factors, which is the same number read the other way as prevention potential. The Commission's own caveat is that "some associations might be only partly causal".

 Population attributable fraction of dementia systematic review not stated "estimated that the PAF for all 14 risk factors was 45.3%" (Table 1: overall PAF 45.3%, rounded 45%); high LDL cholesterol unweighted PAF 18.7%, weighted 6.9%, rounded 7%; untreated vision loss unweighted 6.0%, weighted 2.2%, rounded 2% The Lancet 2024
✓ Peer-reviewed PMID 39096926
Amyloid and tau PET (appropriate use criteria) Care, carers and services Treatment No direction reported
why

Appropriate use criteria rated by consensus: for amyloid PET seven of 17 scenarios were rated appropriate, two uncertain and eight rarely appropriate; for tau PET five, six and six. No effect estimate is reported.

 None measured (appropriate use criteria) systematic review not stated not established — consensus criteria; the abstract reports scenario ratings, not an effect estimate. Alzheimer's & Dementia 2025
✓ Peer-reviewed PMID 39776249
Blood biomarker test (p-tau217 / amyloid ratio) Care, carers and services Treatment Mixed
why

The review's own summary points two ways: CSF biomarker tests were mostly cost-effective against cognitive assessment or imaging, while blood biomarker tests showed mixed results; every included study was model-based.

 Cost-effectiveness of CSF and blood biomarker testing for AD diagnosis across nine model-based economic evaluations systematic review not stated not established — systematic review without meta-analysis; the abstract reports no pooled estimate. European Journal of Health Economics 2026
✓ Peer-reviewed PMID 41385058
Blood biomarker test (p-tau217 / amyloid ratio) Care, carers and services Treatment No direction reported
why

A clinical practice guideline. It sets performance thresholds for blood tests (at least 90% sensitivity and 75% specificity for triage; at least 90% for both to substitute for amyloid PET or CSF) and reports no effect estimate of its own.

 None measured (clinical practice guideline) systematic review not stated not established — guideline; recommendations rather than an effect estimate. Alzheimer's & Dementia 2025
✓ Peer-reviewed PMID 40729527
Cost-effectiveness of anti-amyloid antibody Care, carers and services Treatment Mixed
why

The review splits by drug class: at $100,000 per QALY every study found memantine cost-effective and more than half found the cholinesterase inhibitors so, whereas aducanumab, lecanemab and donanemab were not cost-effective in any study. A value result, not a clinical harm.

 Cost-effectiveness of FDA-approved AD drugs across 23 published analyses (memantine, cholinesterase inhibitors, anti-amyloid antibodies) systematic review not stated At a willingness-to-pay (WTP) threshold of $100,000/QALY, all studies found memantine cost-effective, and more than half reported cost-effectiveness for donepezil, rivastigmine, and galantamine. Aducanumab, lecanemab, and donanemab were not cost-effective in any study. Under the WTP threshold of $150,000/QALY, value-based prices for aducanumab, lecanemab, and donanemab were estimated below $5,960, $15,700, and $33,700, respectively Journal of Alzheimer's Disease 2026
✓ Peer-reviewed PMID 41837605
Diagnostic evaluation and disclosure guideline Care, carers and services Treatment No direction reported
why

A clinical practice guideline. It sets out a structured, patient-centred process for evaluating, diagnosing and disclosing suspected Alzheimer's disease or related dementias in any practice setting, and reports no effect estimate.

 None measured (clinical practice guideline for primary care) systematic review not stated not established — guideline; the abstract reports no effect estimate. Alzheimer's & Dementia 2024
✓ Peer-reviewed PMID 39713942
Respite care Care, carers and services Treatment No effect
why

Three trials comparing respite with no respite found no significant benefit on any carer outcome; the four included trials were too different to pool.

 Carer burden and institutionalisation systematic review 753 No significant benefit found on any caregiver outcome Cochrane Database of Systematic Reviews 2014
✓ Peer-reviewed PMID 24435941
Cognitive training Cognitive activity Treatment Benefit
why

Which intervention helped depended on severity: stimulation for cognition at any severity, training for global cognition in mild dementia, rehabilitation for function in mild dementia and for carer burden. Heterogeneity was high.

 Global cognitive function; functional ability; carer burden systematic review not stated Cognitive stimulation effective for cognitive function at any severity; individual and group cognitive training effective for global cognition in mild dementia; cognitive rehabilitation effective for functional abilities in mild dementia and most effective for reducing carer burden GeroScience 2025
✓ Peer-reviewed PMID 39485657
Anti-amyloid antibody Medicines Treatment Harm
why

The review's subject is the harm itself: brain swelling and microbleeds caused by the drugs.

 ARIA incidence and severity systematic review not stated "ARIA-E and ARIA-H occurred in 12.6% and 17.3% of participants on lecanemab, respectively" (CLARITY-AD); "ARIA-E and ARIA-H occurred in 24% and 31% of participants on donanemab, respectively" (TRAILBLAZER-ALZ-2); APOE e4 homozygotes "may have ~2.5 to 5 times greater risk for incident ARIA-E and for ARIA-H" Alzheimer's & Dementia 2026
✓ Peer-reviewed PMID 42015334

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