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Find studies

Showing 26–50 of 237 studies in How common it is · tagged Risk Factors (page 2 of 10) · 31,380 in the whole library · How the 0–100 score works

Download bibliography of these 237 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.

Pooled clinical and neuropathologic data from 3 prospective cohort studies indicate that TBI with LOC is associated with risk for Lewy body accumulation, progression of parkinsonism, and PD, but not dementia, AD, neuritic plaques, or neurofibrillary tangles. 5 key findings →

Design: cohort study Participants: 7,130 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

Contribution of Modifiable Midlife and Late-Life Vascular Risk Factors to Incident Dementia

✓ Peer-reviewed alzhub usefulness score 69 out of 100. JAMA Neurology 2025-07-01

A total of 7731 participants were included in analysis of risk factors measured at age 45 to 54 years (4494 female [58%]; 2207 Black [29%]; 5524 White [71%]), 12 274 contributed to analysis of risk factors measured at age 55 to 64 years (6698 female [55%]; 2886 Black [24%]; 9388 White [76%]), and 6787 contributed to analysis of risk factors measured at age 65 to 74 years (3764 female [56%], 1375 Black [20%]; 5412 White [80%]). 3 key findings →

Design: cohort Participants: 12,274 Evidence: moderate

Influence of education and occupation on the incidence of Alzheimer's disease

✓ Peer-reviewed alzhub usefulness score 69 out of 100. JAMA 1994-04-01

The data suggest that increased educational and occupational attainment may reduce the risk of incident AD, either by decreasing ease of clinical detection of AD or by imparting a reserve that delays the onset of clinical manifestations. 2 key findings →

Design: cross-sectional Participants: 593 Evidence: moderate

Diabetes, even prediabetes and changes of diabetes-related biochemical indicators, predicted increased incidence of cognitive impairment and dementia. 3 key findings →

Design: systematic review Evidence: high

Patients with osteoarthritis had excess all cause mortality compared with the general population (standardised mortality ratio 1.55, 95% confidence interval 1.41 to 1.70). 2 key findings →

Design: cohort study Participants: 1,163 Evidence: moderate

Is dementia incidence declining?: Trends in dementia incidence since 1990 in the Rotterdam Study

✓ Peer-reviewed alzhub usefulness score 69 out of 100. Neurology 2012-05-02

In the 1990 subcohort (25,696 person-years), 286 persons developed dementia, and in the 2000 subcohort (8,384 person-years), 49 persons. 4 key findings →

Design: cohort study Participants: 5,727 Evidence: moderate

Incidence of Dementia over Three Decades in the Framingham Heart Study

✓ Peer-reviewed alzhub usefulness score 68 out of 100. New England Journal of Medicine 2016

This long-running Massachusetts study tracked dementia rates over more than 30 years and found that a given person's chance of developing dementia at a given age has been steadily falling since the late 1970s. The decline was seen mainly in people with at least a high school education. 4 key findings →

Design: cohort Participants: 5,205 Evidence: high

Incidence and Prevalence of Frontotemporal Dementia: A Systematic Review and Meta-Analysis

✓ Peer-reviewed alzhub usefulness score 67 out of 100. JAMA Neurology 2025-11-01

In this systematic review and meta-analysis, estimates indicate that FTD is comparable in frequency to dementia with Lewy bodies and occurs at higher rates than progressive supranuclear palsy, corticobasal syndrome, and amyotrophic lateral sclerosis. 5 key findings →

Design: meta-analysis Evidence: moderate

Of 23 558 people without pre-existing dementia, 4135 (17·6%) had an admission with delirium. 5 key findings →

Design: cohort Participants: 23,558 Evidence: moderate

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

Plasma Abeta(1-40) and Abeta(1-42) and the risk of dementia: a prospective case-cohort study

✓ Peer-reviewed alzhub usefulness score 67 out of 100. The Lancet. Neurology 2006-08-01

High concentrations of Abeta(1-40) but not Abeta(1-42) at baseline were associated with an increased risk of dementia. 5 key findings →

Design: cohort study Participants: 6,713 Evidence: moderate

During mean follow-up of 2.1 (range 1.5-3.4) years, 146 incident cases of dementia were detected, of which 105 were Alzheimer's disease. 3 key findings →

Design: case-control study Participants: 6,870 Evidence: moderate

Our findings indicate that quantitative gait measures predict future risk of cognitive decline and dementia in initially non-demented older adults. 4 key findings →

Design: cohort study Participants: 427 Evidence: moderate

We estimated the remaining lifetime risks of developing Alzheimer's disease (AD) and dementia from all causes, based on data from longitudinal population studies. 5 key findings →

Design: longitudinal study Participants: 198 Evidence: moderate

SMI and EMCI with self-reported concerns were associated with the same risk of AD dementia, suggesting that pre-LMCI risk conditions should be extended to SMI with concerns. 5 key findings →

Design: cohort study Participants: 2,892 Evidence: moderate

Our cohort of 1,958,191 people from UK general practices had a median age at baseline of 55 years (IQR 45-66) and a median follow-up of 9·1 years (IQR 6·3-12·6). 4 key findings →

Design: cohort study Participants: 1,958,191 Evidence: moderate

The development of MCI is associated with measurements of cognition and depression, racial and constitutional factors, and cerebrovascular disease. 5 key findings →

Design: longitudinal study Participants: 927 Evidence: moderate

A Comparison of the Prevalence of Dementia in the United States in 2000 and 2012

✓ Peer-reviewed alzhub usefulness score 65 out of 100. JAMA Internal Medicine 2017-01-01

Comparing two nationally representative surveys of older Americans 12 years apart, researchers found the share of seniors with dementia fell substantially, from 11.6% in 2000 to 8.8% in 2012. 4 key findings →

Design: cross-sectional Participants: 21,057 Evidence: high

By pooling two long-running community studies from the same region of Pennsylvania, researchers compared dementia rates across people born in different decades, from the 1900s to the 1940s. Each successively younger birth cohort had a substantially lower risk of developing dementia at a given age, with the youngest group's risk about a quarter of the oldest group's. This adds US evidence, independent of Framingham, that generational health improvements are lowering dementia risk. 4 key findings →

Design: cohort Participants: 3,010 Evidence: high

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

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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 31,380 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.

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 31,380 records, built mostly from automated pulls of Europe PMC (65.6% of the library) and OpenAlex (16.2%), 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.

1,048 records (3.3% of the library) are not peer-reviewed — 973 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    Where this research is being discussed: events