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Find studies

Showing 1–25 of 32 studies in How common it is with an author at Harvard University (US) (page 1 of 2) · 30,180 in the whole library · How the 0–100 score works

Download bibliography of these 32 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 incidence rate of dementia in Europe and North America has declined by 13% per decade over the past 25 years, consistently across studies. 2 key findings →

Design: cohort study Participants: 49,202 Evidence: moderate

The overall conversion rate from iRBD to an overt neurodegenerative syndrome was 6.3% per year, with 73.5% converting after 12-year follow-up. 5 key findings →

Participants: 1,280 Evidence: moderate

The study cohort included 568 patients (289 [50.9%] men; mean [SD] age, 70.5 [16.1] years) who died in the hospital or were discharged to hospice. 1 key finding →

Design: cohort study Participants: 568 Evidence: moderate

However, the advisory did not apply to conventional antipsychotic medications; the risk of death with these older agents is not known. 1 key finding →

Design: cohort study Participants: 22,890 Evidence: moderate

Antipsychotic drug use and mortality in older adults with dementia

✓ Peer-reviewed alzhub usefulness score 72 out of 100. Annals of internal medicine 2007-06-01

Atypical antipsychotic use is associated with an increased risk for death compared with nonuse among older adults with dementia. 5 key findings →

Design: cohort study Participants: 27,259 Evidence: moderate

Cancer survivors had a lower risk of Alzheimer's disease than those without cancer, and patients with Alzheimer's disease had a lower risk of incident cancer. 5 key findings →

Design: cohort study Participants: 1,278 Evidence: moderate

APOE4 homozygozity represents a distinct genetic form of Alzheimer's disease

✓ Peer-reviewed alzhub usefulness score 69 out of 100. Nature medicine 2024-05-06

This study aimed to evaluate the impact of APOE4 homozygosity on Alzheimer's disease (AD) by examining its clinical, pathological and biomarker changes to see whether APOE4 homozygotes constitute a distinct, genetically determined form of AD. 2 key findings →

Participants: 3,297 Evidence: low

Frailty, comorbidities, and other age-related diseases were associated with a higher risk of dementia but did not account for the elevated dementia risk observed after severe infections. 3 key findings →

Design: cohort Participants: 449,223 Evidence: moderate

FastSurfer - A fast and accurate deep learning based neuroimaging pipeline

✓ Peer-reviewed alzhub usefulness score 67 out of 100. NeuroImage 2020-06-08

Traditional neuroimage analysis pipelines involve computationally intensive, time-consuming optimization steps, and thus, do not scale well to large cohort studies with thousands or tens of thousands of individuals. 5 key findings →

Design: cohort study Evidence: moderate

Older, healthy women with decreased circadian activity rhythm amplitude and robustness, and delayed rhythms have increased odds of developing dementia and MCI. 3 key findings →

Design: cross-sectional Evidence: moderate

The preponderance of epidemiologic and tissue compositional studies supports a protective effect of omega-3 EFA intake, particularly eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), in mood disorders. 3 key findings →

Design: meta-analysis Evidence: high

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

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

Moving beyond the prevalent exposure design for causal inference in dementia research

✓ Peer-reviewed alzhub usefulness score 61 out of 100. The Lancet Healthy Longevity 2025-01-30

As randomised trials are not always feasible or practical, observational studies remain crucial for addressing many causal questions in the dementia prevention field. 1 key finding →

Design: cohort study Evidence: high

In both the mortality and readmission cohorts we found significant associations with each pollutant. 5 key findings →

Design: retrospective cohort Participants: 118 Evidence: moderate

Although air pollution is well known to be harmful to the lung and airways, it can also damage most other organ systems of the body. 4 key findings →

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 30,180 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 30,180 records, built mostly from automated pulls of Europe PMC (64.2% of the library) and OpenAlex (16.9%), 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.

1,037 records (3.4% of the library) are not peer-reviewed — 964 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