27,380 Alzheimer's and dementia studies in plain English, each scored out of 100.
Study-level data from 14 studies, 2,310,330 individuals, and 102,174 dementia case patients were included. 3 key findings →
Design: meta-analysis Participants: 2,310,330 Evidence: high
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In analyses that addressed bias due to reverse causation, physical inactivity was not associated with all-cause dementia or Alzheimer's disease, although an indication of excess dementia risk was observed in a subgroup of physically inactive individuals who developed cardiometabolic disease. 2 key findings →
Design: meta-analysis Participants: 404 Evidence: high
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A total of 267 (3.8%) women had diabetes and 297 (4.2%) had IFG. 3 key findings →
Design: randomized controlled trial Participants: 267 Evidence: high
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Among 10 095 participants (67.3% men; aged 35-55 years in 1985-1988), a total of 1710 cases of diabetes and 639 cases of dementia were recorded over a median follow-up of 31.7 years. 3 key findings →
Design: cohort study Participants: 95 Evidence: moderate
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This study examined the association of diabetes with the onset of dementia (including Alzheimer's disease (AD), vascular dementia (VD) and any dementia) and mild cognitive impairment (MCI) by using a quantitative meta-analysis of longitudinal studies. 2 key findings →
Design: meta-analysis Participants: 6,184 Evidence: high
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Central obesity in midlife increases risk of dementia independent of diabetes and cardiovascular comorbidities. 3 key findings →
Design: longitudinal study Participants: 1,049 Evidence: moderate
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Midlife and late-life risk factors contributed to 22.7% and 16.5% of total dementia cases, respectively. 5 key findings →
Design: meta-analysis Participants: 37,931 Evidence: high
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Pooled HRs indicated depression present in late-life (HR 1.95, 95% CI: 1.68–2.26; I 2 = 77.5%) and midlife (HR 1.56, 95% CI: 1.12–2.18; I 2 = 97.5%) significantly increased risk of all-cause dementia. 2 key findings →
Design: meta-analysis Participants: 901,762 Evidence: high
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The relationship between body mass index (BMI) (in midlife and late-life) and dementia was investigated in meta-analyses of 16 articles reporting on 15 prospective studies. 5 key findings →
Design: meta-analysis Participants: 624 Evidence: high
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A statistically significant age-adjusted association was observed between the A1C level and the score on all four cognitive tests. 3 key findings →
Evidence: low
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A total of 19 reviews containing 37 meta-analyses were included umbrella review. 5 key findings →
Design: systematic review Participants: 19 Evidence: high
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Among older women, those with sleep-disordered breathing compared with those without sleep-disordered breathing had an increased risk of developing cognitive impairment. 4 key findings →
Design: cross-sectional Participants: 60 Evidence: low
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Both overweight and obesity at midlife independently increase the risk of dementia, AD, and VaD. 3 key findings →
Design: case-control study Participants: 350 Evidence: moderate
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Previously increased blood pressure may increase the risk for dementia by inducing small-vessel disease and white-matter lesions. 5 key findings →
Design: longitudinal study Participants: 382 Evidence: moderate
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The authors assessed the association of smoking with dementia and cognitive decline in a meta-analysis of 19 prospective studies with at least 12 months of follow-up. 3 key findings →
Design: meta-analysis Participants: 26,374 Evidence: high
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Stroke is a strong, independent, and potentially modifiable risk factor for all-cause dementia. 2 key findings →
Design: meta-analysis Evidence: high
Full summary, score breakdown and related studies → Original source Free full text
Our findings support the hypothesis that depression is a risk factor for dementia and suggest that recurrent depression is particularly pernicious. 3 key findings →
Design: longitudinal study Participants: 1,239 Evidence: moderate
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Controversies persist regarding the association between blood pressure (BP) and the risks of cognitive impairment and dementia due to inconsistent definitions of BP exposure and varying population characteristics. 5 key findings →
Design: systematic review Evidence: high
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To determine incidence of dementia in type 2 diabetic (T2DM) patients, and whether there are adverse or favorable effects of oral agents (OA) in DM, we obtained a representative cohort of 800,000 from Taiwan’s National Health Insurance database. 2 key findings →
Participants: 127,209 Evidence: moderate
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If the associations we observed are causal, then air pollution from traffic might be an important risk factor for vascular dementia and Alzheimer's disease. 3 key findings →
Design: prospective cohort Participants: 1,806 Evidence: moderate
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We performed a systematic review and meta-analysis to explore whether type 2 diabetes mellitus (T2DM) increases the risk of Alzheimer's disease (AD). 3 key findings →
Design: systematic review Participants: 15 Evidence: high
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Elevated blood pressure during midlife, persistence of elevated blood pressure into late life, and, among nonhypertensives, a steep decline in blood pressure during mid- to late life were associated with an increased dementia risk in a community-based cohort. 5 key findings →
Participants: 1,440 Evidence: moderate
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The study consisted of 20 400 patients (9264 female [45.4%]; 1576 Black [7.7%], 3944 Latinx [19.3%], and 10 480 White [51.4%]), including 5100 patients with mTBI (median [IQR] age, 36.0 [25.0-51.0] years), 5100 patients with msTBI (median [IQR age, 35.0 [25.0-52.0] years), and 10 200 matched patients in the control group (median [IQR] age, 36.0 [25.0-51.0] years). 5 key findings →
Design: cohort study Participants: 400 Evidence: moderate
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Several studies report an association between REM Sleep Behavior Disorder (RBD) and neurodegenerative diseases, in particular synucleinopathies. 5 key findings →
Design: meta-analysis Evidence: high
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Vascular risk factors, such as type 2 diabetes, hypertension, obesity and dyslipidaemia often co-occur. 3 key findings →
Design: longitudinal study Participants: 14 Evidence: moderate
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Free full text links and the Full text may need a subscription label come from Unpaywall, Europe PMC and OpenAlex records of free copies, checked 10 Oct 2026. A study with neither is unknown, not paywalled. Show only studies that are free to read
This is alzhub's own score. It is not an official metric, not an impact factor, and no journal, publisher or ranking body endorses it. We built it so that a reader who is not a scientist can tell a landmark trial from a conference abstract without having to already know the difference. Every point comes from one of 20 components, all of them printed on the study itself, so you can disagree with our arithmetic rather than having to trust the total.
Journals are placed in ordered tiers, never given a numeric impact factor — we could not verify current impact factors from a source we control, and an invented one would be worse than none. Tier 1 is the top-tier general journals (NEJM, The Lancet, JAMA, Nature, Science, Nature Medicine); tier 2 is the leading specialty journals; tier 3 is every other peer-reviewed journal. A separate part scores how much the journal's own papers are cited, which tells the tier-3 journals apart.
Two rules we don't bend. First, we never fill in a missing value: if a record does not state a sample size or a design, that component scores zero, and if we simply have no data for a part, such as a citation count, that part is left out and the study is scored on the parts we could check. The study card says which. Second, anything that is not a peer-reviewed article is capped at 16/100 and carries a warning chip — so a conference abstract or a company press release can never outrank a peer-reviewed paper, no matter how good it looks.
We rank a rigorous null result — a good trial showing that something does not work — above an early positive finding. Someone deciding whether to buy a supplement is served by that, and the rigour is already counted by the design and journal components.
The score is computed from the published data alone and is reproducible: the same file always yields the same numbers.
See the whole rubric drawn out → — four charts covering all 27,380 studies: how the scores are spread and where the cap bites, which of the 20 components the library is strong and weak on, which subjects rest on stronger evidence, and what kinds of study each subject is actually built from.
This is a large sample of the Alzheimer's literature, not an exhaustive index of it. It holds 27,380 records, built mostly from automated pulls of Europe PMC (60.6% of the library) and OpenAlex (18.6%), plus smaller pulls from PubMed, Crossref and medRxiv. If a study, a drug, or a finding isn't here, that is not evidence it doesn't exist in the literature — it may simply not have been pulled in yet.
1,032 records (3.8% of the library) are not peer-reviewed — 962 of those are preprints posted before any journal review, and the rest are conference abstracts, regulatory notices and reports. Every study card on this page states its status plainly, and the score above is capped for anything that isn't a peer-reviewed article.
See the full, machine-readable breakdown of this library's coverage →