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Find studies

Showing 1–25 of 156 studies in How common it is · free to read · tagged Risk Factors (page 1 of 7) · 31,380 in the whole library · How the 0–100 score works

Download bibliography of these 156 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

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

A nurse-led, multidomain intervention did not result in a reduced incidence of all-cause dementia in an unselected population of older people. 3 key findings →

Design: randomized controlled trial Participants: 3,526 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

6-month consequences of COVID-19 in patients discharged from hospital: a cohort study

✓ Peer-reviewed alzhub usefulness score 74 out of 100. Lancet (London, England) 2021-01-08

After multivariable adjustment, patients showed an odds ratio (OR) 1·61 (95% CI 0·80-3·25) for scale 4 versus scale 3 and 4·60 (1·85-11·48) for scale 5-6 versus scale 3 for diffusion impairment; OR 0·88 (0·66-1·17) for scale 4 versus scale 3 and OR 1·77 (1·05-2·97) for scale 5-6 versus scale 3 for anxiety or depression, and OR 0·74 (0·58-0·96) for scale 4 versus scale 3 and 2·69 (1·46-4·96) for scale 5-6 versus scale 3 for fatigue or muscle weakness. 2 key findings →

Design: cohort study Participants: 94 Evidence: moderate

The number of years of formal education completed by individuals is positively correlated with their cognitive function throughout adulthood and predicts lower risk of dementia late in life. 4 key findings →

Design: meta-analysis Evidence: high

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

Long-term health benefits of physical activity--a systematic review of longitudinal studies

✓ Peer-reviewed alzhub usefulness score 71 out of 100. BMC public health 2013-09-08

This review revealed a paucity of long-term studies on the relationship between physical activity and the incidence of NCD. 3 key findings →

Design: cross-sectional Participants: 288,724 Evidence: moderate

Parkinson risk in idiopathic REM sleep behavior disorder: preparing for neuroprotective trials

✓ Peer-reviewed alzhub usefulness score 71 out of 100. Neurology 2015-02-13

Using stratification with simply assessed markers, it is now not only possible, but practical to include patients with RBD in neuroprotective trials against Parkinson disease, multiple system atrophy, and dementia with Lewy bodies. 3 key findings →

Design: prospective cohort Participants: 89 Evidence: moderate

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

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

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

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

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

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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.

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
  • Randomized / 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
  • Multicenter 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