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Find studies

Showing 126–150 of 522 studies in How common it is (page 6 of 21) · 27,780 in the whole library · How the 0–100 score works

Download bibliography of the first 500 of these studies, in this order: BibTeX (.bib) · RIS (.ris)

Browse by subject, author or institution

Each number is how many studies that link shows, with your other filters kept.

What “How common it is” covers

How common it is — Counting patterns across whole populations: who gets dementia, at what age, and how that is changing.

A note on reading research. One study is rarely the final word.

We try to note the size of a study, whether it was in humans or animals, and how early-stage the finding is. If a summary here doesn't make that clear, treat it with extra caution and check the original source.

The pooled sample comprised 4657 participants (30% women) aged ≥ 60 years (mean age was 74 years at sleep assessment). 5 key findings →

Design: cohort study Participants: 2,374 Evidence: moderate

One million nine hundred twenty-five thousand, five hundred sixty-three individuals were included across the four databases with a median follow-up ranging from 5.6 to 8.4 years. 4 key findings →

Design: meta-analysis Evidence: high

AS01-adjuvanted shingles (herpes zoster) vaccination is associated with a lower risk of dementia, but the underlying mechanisms are unclear. 3 key findings →

Design: cohort study Participants: 436,788 Evidence: moderate

Detection Bias in EHR-Based Research on Clinical Exposures and Dementia

✓ Peer-reviewed alzhub usefulness score 64 out of 100. JAMA Network Open 2025-04-23

Among 228 392 participants from UKB (n = 137 374; mean [SD] age at baseline, 62.5 [4.1] years; 53.8% female) and AOU (n = 91 018; mean [SD] age at baseline, 66.9 [7.8] years; 57.1% female), those with a history of a clinical exposure at baseline had higher dementia incidence rates compared with those without such history. 5 key findings →

Design: cohort study Participants: 137 Evidence: moderate

Delirium is common, persistent, and independently associated with poor functional recovery 1 month after hip fracture even after adjusting for prefracture frailty. 3 key findings →

Design: cohort study Evidence: moderate

Mild cognitive impairment, amnestic type: an epidemiologic study

✓ Peer-reviewed alzhub usefulness score 63 out of 100. Neurology 2004-07-01

In this community-based sample, 3 to 4% of nondemented persons met MCI operational criteria; despite increased risk of progressing to dementia, a substantial proportion also remained stable or reverted to normal during follow-up. 3 key findings →

Participants: 1,248 Evidence: moderate

Hypertension and cerebral white matter lesions in a prospective cohort study

✓ Peer-reviewed alzhub usefulness score 63 out of 100. Brain : a journal of neurology 2002-04-01

White matter lesions are frequently found on cerebral MRI scans of elderly people and are thought to be important in the pathogenesis of dementia. 5 key findings →

Design: cross-sectional Participants: 1,077 Evidence: low

We conclude that patients with mild cognitive impairment and depression are at more than twice the risk of developing dementia of Alzheimer type as those without depression. 4 key findings →

Design: cohort study Participants: 114 Evidence: moderate

Severe psoriasis is associated with an increased risk of death from a variety of causes, with cardiovascular death being the most common aetiology. 4 key findings →

Design: cohort study Participants: 3,603 Evidence: moderate

Distinct associations between different traffic noise exposures and incident dementia subtypes were found in this large UK prospective cohort study. 3 key findings →

Design: cohort study Participants: 502,416 Evidence: moderate

All indicators of atherosclerosis were associated with dementia (odds ratios ranging from 1.3 to 1.9) and its major subtypes Alzheimer's disease (odds ratios 1.3-1.8) and vascular dementia (odds ratios 1.9-3.2). 4 key findings →

Participants: 284 Evidence: low

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Where “Free full text” comes from

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

How the 0–100 score works — and why some entries are capped

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.

  • Journal tier up to 10 pts
  • Journal's citation record up to 4 pts
  • Study design up to 12 pts
  • Strength of evidence up to 5 pts
  • Peer-review validation up to 10 pts
  • How recent up to 5 pts
  • Sample size up to 4 pts
  • Effect reported up to 3 pts
  • Studied in people up to 3 pts
  • Randomised / blinded up to 2 pts
  • Times cited up to 7 pts
  • Citations per year up to 5 pts
  • Impact for its field and year up to 6 pts
  • Cited by studies here up to 6 pts
  • Still being cited up to 4 pts
  • Senior author's track record up to 4 pts
  • Institution's track record up to 3 pts
  • Multi-centre collaboration up to 3 pts
  • Indexed in PubMed up to 2 pts
  • Free to read up to 2 pts

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 27,780 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.

What this library is — and isn't

This is a large sample of the Alzheimer's literature, not an exhaustive index of it. It holds 27,780 records, built mostly from automated pulls of Europe PMC (61.1% of the library) and OpenAlex (18.3%), 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.

1,034 records (3.7% 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 →

Newest studies, as a dated timeline →    Atom feed