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Find studies

Showing 1–25 of 134 studies in How common it is (page 1 of 6) · 28,180 in the whole library · How the 0–100 score works

Download bibliography of these 134 studies, in this order: BibTeX (.bib) · RIS (.ris)

Showing 134 studies tagged prospective — clear

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

In the estrogen-alone trial, 47 participants were diagnosed with probable dementia, of whom 28 were assigned to CEE and 19 to placebo (hazard ratio [HR], 1.49; 95% confidence interval [CI], 0.83-2.66). 3 key findings →

Participants: 4,532 Evidence: high

Older people with SMC but no objective complaints are twice as likely to develop dementia as individuals without SMC. 3 key findings →

Design: meta-analysis Participants: 15,009 Evidence: high

Cumulative use of strong anticholinergics and incident dementia: a prospective cohort study

✓ Peer-reviewed alzhub usefulness score 77 out of 100. JAMA internal medicine 2015-03-01

The most common anticholinergic classes used were tricyclic antidepressants, first-generation antihistamines, and bladder antimuscarinics. 4 key findings →

Design: cohort study Participants: 3,434 Evidence: moderate

Leisure-time physical activity at midlife and the risk of dementia and Alzheimer's disease

✓ Peer-reviewed alzhub usefulness score 77 out of 100. The Lancet. Neurology 2005-11-01

Leisure-time physical activity at midlife at least twice a week was associated with a reduced risk of dementia and AD (odds ratio [OR] 0.48 [95% CI 0.25-0.91] and 0.38 [0.17-0.85], respectively), even after adjustments for age, sex, education, follow-up time, locomotor disorders, APOE genotype, vascular disorders, smoking, and alcohol drinking. 2 key findings →

Participants: 1,449 Evidence: moderate

Midlife cardiovascular risk factors and risk of dementia in late life

✓ Peer-reviewed alzhub usefulness score 76 out of 100. Neurology 2005-01-01

The presence of multiple cardiovascular risk factors at midlife substantially increases risk of late-life dementia in a dose dependent manner. 5 key findings →

Design: cohort study Participants: 8,845 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 relationships between alcohol consumption and dementia and cognitive decline were investigated in a systematic review including meta-analyses of 15 prospective studies. 4 key findings →

Design: systematic review Participants: 14,646 Evidence: high

Diabetes mellitus and the risk of dementia: The Rotterdam Study

✓ Peer-reviewed alzhub usefulness score 72 out of 100. Neurology 1999-12-01

The diabetes attributable risk for dementia of 8.8% suggests that diabetes may have contributed to the clinical syndrome in a substantial proportion of all dementia patients. 2 key findings →

Design: cohort study Participants: 126 Evidence: moderate

Midlife vascular risk factor exposure accelerates structural brain aging and cognitive decline

✓ Peer-reviewed alzhub usefulness score 72 out of 100. Neurology 2011-08-01

Our aim was to test the association of vascular risk factor exposure in midlife with progression of MRI markers of brain aging and measures of cognitive decline. 1 key finding →

Design: cohort study Participants: 1,352 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

Older adults with CVD other than stroke had a higher risk of dementia and AD than did those without CVD. 5 key findings →

Design: cohort study Participants: 3,602 Evidence: moderate

Leisure activities and the risk of dementia in the elderly

✓ Peer-reviewed alzhub usefulness score 71 out of 100. The New England journal of medicine 2003-06-01

Participation in leisure activities is associated with a reduced risk of dementia, even after adjustment for base-line cognitive status and after the exclusion of subjects with possible preclinical dementia. 5 key findings →

Design: prospective cohort Participants: 469 Evidence: moderate

Between 2001, and 2012, we identified 243 611 incident cases of dementia, 31 577 cases of Parkinson's disease, and 9247 cases of multiple sclerosis. 3 key findings →

Design: cohort study 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

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

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

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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 28,180 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 28,180 records, built mostly from automated pulls of Europe PMC (61.7% of the library) and OpenAlex (18.1%), 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