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Find studies

Showing 26–50 of 259 studies in Risk factors of type cohort or longitudinal study (page 2 of 11) · 31,380 in the whole library · How the 0–100 score works

Download bibliography of these 259 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 “Risk factors” covers

Risk factors — Conditions, exposures and habits linked to a higher or lower chance of dementia, and how strong each link is.

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.

Of 1,164 participants (mean age 73.5 years, 64% women), 580 (49.8%) had mild hearing impairment and 196 (16.8%) had moderate/severe hearing impairment. 5 key findings →

Design: longitudinal study Participants: 1,164 Evidence: moderate

The combinations of hearing and proprioceptive impairment and hearing, vision, and proprioceptive impairment, were positively correlated with cDVR (β = 0.087 and p = 0.036, β = 0.110 and p = 0.018, respectively). 3 key findings →

Design: longitudinal study Participants: 174 Evidence: moderate

Among 5,699 participants (mean age: 70±8 years), we observed total PM2.5 concentrations ranging from 16 to 206 μg/m3. 5 key findings →

Design: longitudinal study Participants: 5,699 Evidence: moderate

Evidence on the association between air pollution and dementia is accumulating but still inconclusive, and the potential effect modification by genetics is unclear. 2 key findings →

Design: cohort study Participants: 227,840 Evidence: moderate

If the associations we observed are causal, then air pollution from traffic might be an important risk factor for vascular dementia and Alzheimer's disease. 3 key findings →

Design: prospective cohort Participants: 1,806 Evidence: moderate

The potential determinants of cognitive decline identified in this study, in particular modifiable risk factors, should be tested in the context of randomised controlled trials. 2 key findings →

Design: longitudinal study Participants: 626 Evidence: high

Screening for IC impairments identifies older adults at higher risk of incident frailty and incident IADL/ADL disability. 3 key findings →

Design: longitudinal study Participants: 759 Evidence: moderate

Several studies with animal research associate air pollution in Alzheimer's disease (AD) neuropathology, but the actual impact of air pollution on the risk of AD is unknown. 3 key findings →

Design: cohort study Participants: 95,690 Evidence: moderate

In this cohort study, higher residential PM2.5 levels, especially from agriculture and wildfires, were associated with higher rates of incident dementia, providing further evidence supporting PM2.5 reduction as a population-based approach to promote healthy cognitive aging. 5 key findings →

Design: cohort study Participants: 27 Evidence: moderate

Road traffic noise, air pollution, and risk of dementia - results from the Betula project

✓ Peer-reviewed alzhub usefulness score 69 out of 100. Environmental research 2018-06-14

We found no evidence that exposure to road traffic noise, either independently or in combination with traffic air pollution, was associated with risk of dementia in our study area. 5 key findings →

Design: longitudinal study Participants: 1,721 Evidence: moderate

Midlife insomnia (fully adjusted hazard ratio = 1.24, 95% confidence interval = 1.02-1.50) and late-life terminal insomnia (fully adjusted odds ratio = 1.94, 95% confidence interval = 1.08-3.49) were associated with a higher dementia risk. 3 key findings →

Design: longitudinal study Participants: 1,446 Evidence: moderate

Their results on motor testing from the preceding years were plotted, and then assessed with regression analysis, to determine when markers first deviated from normal values. 3 key findings →

Design: cohort study Participants: 78 Evidence: moderate

A total of 3,056 participants without diabetes treatment and 480 with diabetes treatment were included (mean age at baseline, 75.1 years; mean 7.5 years of follow-up). 5 key findings →

Design: cohort study Participants: 3,056 Evidence: moderate

Huntington's disease patients had a lower prevalence of hypertension compared with age-matched gene-negative controls. 5 key findings →

Design: longitudinal study Participants: 14,534 Evidence: moderate

Trajectories of systolic BP were separated markedly around 25 to 45 years of age, with the group below the median of cognition score having higher levels of systolic BP than the group above the median. 5 key findings →

Design: longitudinal study Participants: 912 Evidence: moderate

This study replicated research showing that education was positively associated with cognition at baseline. 5 key findings →

Design: cohort study Participants: 28,417 Evidence: moderate

Late-life depression is not associated with dementia-related pathology

✓ Peer-reviewed alzhub usefulness score 68 out of 100. Neuropsychology 2016-02

In the full cohort, 9.4% were diagnosed with major depression and 8.6% had chronically elevated depressive symptoms, both of which were related to adverse cognitive outcomes. 5 key findings →

Design: cohort study Participants: 1,965 Evidence: moderate

In the first year of follow-up, increased exposure to all air pollutants was associated with an increase in the use of CMHTs in a dose-response manner. 5 key findings →

Design: longitudinal study Participants: 5,024 Evidence: moderate

Of 6 952 440 vaccinated patients in the derivation cohort, 5 150 310 (74.1%) had two vaccine doses. 4 key findings →

Design: cohort study 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