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Find studies

Showing 1–25 of 259 studies in Risk factors of type cohort or longitudinal study (page 1 of 11) · 28,180 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.

Association Between Age at Diabetes Onset and Subsequent Risk of Dementia

✓ Peer-reviewed alzhub usefulness score 77 out of 100. JAMA 2021-04-01

Among 10 095 participants (67.3% men; aged 35-55 years in 1985-1988), a total of 1710 cases of diabetes and 639 cases of dementia were recorded over a median follow-up of 31.7 years. 3 key findings →

Design: cohort study Participants: 95 Evidence: moderate

The cohort study revealed that persistent HI significantly increased the risk of heart disease (P < 0.001, HR 1.63, 95% CI 1.31-2.03), stroke (P 0.004, HR 1.59, 95% CI 1.16-2.18), chronic lung disease (P 0.002, HR 1.53, 95% CI 1.17-1.99), and emotional, nervous, or psychiatric problems (P 0.016, HR 2.03, 95% CI 1.14-3.60). 5 key findings →

Design: cohort study Participants: 504,307 Evidence: moderate

Subjects experiencing multisensory impairments concurrent with visual impairment demonstrated a negative association with cognitive function. 5 key findings →

Design: cohort study Participants: 500,000 Evidence: moderate

In this cohort study of US Medicare beneficiaries, dual sensory impairment was prevalent in older adults and associated with increased risk of dementia. 5 key findings →

Design: cohort study Participants: 7,562 Evidence: moderate

Widening the Spectrum of Risk Factors, Comorbidities, and Prodromal Features of Parkinson Disease

✓ Peer-reviewed alzhub usefulness score 74 out of 100. JAMA neurology 2023-02-01

Consistent with previous reports, risk factors and prodromal features associated with PD included traumatic brain injury, odds ratio (OR), 1.62; 95% CI, 1.36-1.92; alcohol misuse, OR, 1.32; 95% CI, 1.21-1.44; hypertension, OR, 1.29; 95% CI, 1.26-1.31; anosmia, OR, 2.16; 95% CI, 1.59-2.93; and parasomnias (including RBD), OR, 1.62; 95% CI, 1.42-1.84. 4 key findings →

Design: cohort study Participants: 345 Evidence: moderate

Females with MCI exhibited greater baseline GMV than males primarily in the thalamus, caudate, cerebellum, postcentral gyrus, and middle cingulate gyrus, with no differences at the AD stage. 3 key findings →

Design: longitudinal study Participants: 593 Evidence: moderate

Baseline subjective cognitive decline and low cognitive reserve significantly increased the risk of dementia, after 2 years of follow-up. 5 key findings →

Design: longitudinal study Participants: 2,099 Evidence: moderate

Hypertension and Stroke as Mediators of Air Pollution Exposure and Incident Dementia

✓ Peer-reviewed alzhub usefulness score 73 out of 100. JAMA network open 2023-09-05

Among 27 857 participants (mean [SD] age at baseline, 61 [10] years; 15 747 female participants [56.5%]; 19 249 non-Hispanic White participants [69.1%]), 4105 (14.7%) developed dementia during the follow-up period (mean [SD], 10.2 [5.6] years). 5 key findings →

Design: cohort study Participants: 857 Evidence: moderate

Age-related hearing loss is linked to loneliness and poorer cognitive health, but it remains unclear whether loneliness helps explain associations between hearing difficulties and cognitive performance or dementia, and whether these patterns reflect causal pathways or shared underlying liability. 4 key findings →

Design: longitudinal study Participants: 10,375 Evidence: moderate

Both HL and depression are independent risk factors for eventual conversion to dementia. 2 key findings →

Design: longitudinal study Participants: 8,529 Evidence: moderate

Are noise and air pollution related to the incidence of dementia? A cohort study in London, England

✓ Peer-reviewed alzhub usefulness score 71 out of 100. BMJ open 2018-09-11

We have found evidence of a positive association between residential levels of air pollution across London and being diagnosed with dementia, which is unexplained by known confounding factors. 3 key findings →

Design: cohort study Participants: 978 Evidence: moderate

A total of 32,901 (1.12%) participants developed dementia, of which 74.4% and 11.0% were attributable to Alzheimer's disease and vascular dementia, respectively, during the median follow-up of 5.5 years. 5 key findings →

Design: cohort study Participants: 2,930,816 Evidence: moderate

The cognitive reserve (CR) hypothesis posits that individuals can differ in how their brain function is disrupted by pathology associated with aging and neurodegeneration. 3 key findings →

Design: longitudinal study Participants: 490 Evidence: moderate

Among 952 participants (mean age at first neuropsychological assessment = 69±8 years, 62% women, 17% Black, 13% white, 68% Hispanic), 24% developed MCI/dementia. 4 key findings →

Design: longitudinal study Participants: 952 Evidence: moderate

Recurrent depressive symptoms and the incidence of dementia and mild cognitive impairment

✓ Peer-reviewed alzhub usefulness score 70 out of 100. Neurology 2010-07-01

Our findings support the hypothesis that depression is a risk factor for dementia and suggest that recurrent depression is particularly pernicious. 3 key findings →

Design: longitudinal study Participants: 1,239 Evidence: moderate

Sleep duration had an inverted U-shape relationship with cognitive scores (P <.001); and sleep quality had a positive linear relationship with cognitive scores (P <.001). 5 key findings →

Design: longitudinal study Participants: 10,768 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