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Find studies

Showing 1–25 of 139 studies in Risk factors published 2020 (page 1 of 6) · 27,380 in the whole library · How the 0–100 score works

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 285 participants randomized (suvorexant, N = 142; placebo, N = 143), 277 (97%) completed the trial (suvorexant, N = 136; placebo, N = 141). 4 key findings →

Participants: 142 Evidence: high

Association of Delirium With Long-term Cognitive Decline: A Meta-analysis

✓ Peer-reviewed alzhub usefulness score 76 out of 100. JAMA neurology 2020-11-01

Of 1583 articles, data subjected from the 24 studies (including 3562 patients who experienced delirium and 6987 controls who did not) were included in a random-effects meta-analysis for pooled effect estimates and random-effects meta-regressions to identify sources of study variance. 3 key findings →

Design: systematic review Participants: 3,562 Evidence: high

Evidence-based suggestions are proposed, offering clinicians and stakeholders current guidance for the prevention of AD. 1 key finding →

Design: systematic review Participants: 44 Evidence: high

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

Prognostic factors for severity and mortality in patients infected with COVID-19: A systematic review

✓ Peer-reviewed alzhub usefulness score 72 out of 100. PloS one 2020-11-17

Identified prognostic factors can help clinicians and policy makers in tailoring management strategies for patients with COVID-19 infectious disease while researchers can utilise our findings to develop multivariable prognostic models that could eventually facilitate decision-making and improve patient important outcomes. 2 key findings →

Design: systematic review Participants: 207 Evidence: high

Fruit and Vegetable Intake and Mental Health in Adults: A Systematic Review

✓ Peer-reviewed alzhub usefulness score 70 out of 100. Nutrients 2020-01-01

The most prominent results indicated that high total intake of fruits and vegetables, and some of their specific subgroups including berries, citrus, and green leafy vegetables, may promote higher levels of optimism and self-efficacy, as well as reduce the level of psychological distress, ambiguity, and cancer fatalism, and protect against depressive symptoms. 3 key findings →

Design: systematic review Participants: 5,911 Evidence: high

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

Controversies persist regarding the association between blood pressure (BP) and the risks of cognitive impairment and dementia due to inconsistent definitions of BP exposure and varying population characteristics. 5 key findings →

Design: systematic review Evidence: high

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

Does bilingualism protect against dementia? A meta-analysis

✓ Peer-reviewed alzhub usefulness score 68 out of 100. Psychonomic bulletin & review 2020-10

Evidence suggests that bilingualism may contribute to neuroplasticity and cognitive reserve, allowing individuals to resist cognitive decline associated with Alzheimer's disease progression, although the idea remains controversial. 4 key findings →

Design: meta-analysis Evidence: high

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

These 20 consensus statements on the use of unilateral cochlear implantation in adults with SNHL were relevant to the following 7 key areas of interest: level of awareness of cochlear implantation (1 consensus statement); best practice clinical pathway from diagnosis to surgery (3 consensus statements); best practice guidelines for surgery (2 consensus statements); clinical effectiveness of cochlear implantation (4 consensus statements); factors associated with postimplantation outcomes (4 consensus statements); association between hearing loss and depression, cognition, and dementia (5 consensus statements); and cost implications of cochlear implantation (1 consensus statement). 2 key findings →

Design: systematic review Evidence: high

Increased α-synuclein egress in serum neuronal exosomes precedes the diagnosis of Parkinson's disease, persists with disease progression and in combination with clusterin predicts and differentiates Parkinson's disease from atypical parkinsonism. 2 key findings →

Design: cross-sectional Participants: 314 Evidence: moderate

Association of Neighborhood-Level Disadvantage With Alzheimer Disease Neuropathology

✓ Peer-reviewed alzhub usefulness score 64 out of 100. JAMA Network Open 2020-06-11

The sample consisted of 447 decedents (249 men [56%]; mean [SD] age, 80.3 [9.5] years; median year of death, 2011) spanning 24 years of donation. 5 key findings →

Design: cross-sectional Participants: 24 Evidence: low

Between Jan 1, 2000, and Dec 31, 2016, of 63 038 019 individuals who were aged 65 years or older during the study period, we identified 1·0 million cases of Parkinson's disease and 3·4 million cases of Alzheimer's disease and related dementias based on primary and secondary diagnosis billing codes. 1 key finding →

Design: cohort study Participants: 19 Evidence: moderate

In cognitively unimpaired adults with increased risk for AD, increased exposure to air pollution was suggested to be associated with greater global atrophy and reduced volume and thickness in specific brain areas known to be affected in AD, thus suggesting a potential link between environmental exposures and cerebral vulnerability to AD. 4 key findings →

Design: prospective cohort Participants: 958 Evidence: moderate

Alcohol consumption and sleep quality: a community-based study

✓ Peer-reviewed alzhub usefulness score 61 out of 100. Public health nutrition 2020-11-13

We observed a dose-response association between higher alcohol consumption in 2006 and worse sleep quality in 2012 (Ptrend < 0·001), after adjusting for age, sex, socio-economic status, smoking status, physical activity, obesity, plasma lipid profiles, diabetes and hypertension. 5 key findings →

Design: cross-sectional Participants: 905 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 27,380 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 27,380 records, built mostly from automated pulls of Europe PMC (60.6% of the library) and OpenAlex (18.6%), 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.

1,032 records (3.8% 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