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Research

27,380 Alzheimer's and dementia studies in plain English, each scored out of 100.

Find studies

Showing 451–475 of 522 studies in How common it is (page 19 of 21) · 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.

Other subjects

Authors

Names as each record prints them; the same person can appear under two spellings.

Institutions

From OpenAlex; 12,859 studies have no institution on record and are not counted here.

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.

Global, regional, and national burden of neurological disorders, 1990-2016: a systematic analysis for the Global Burden of Disease Study 2016

✓ Peer-reviewed alzhub usefulness score 45 out of 100. The Lancet. Neurology 2019-03-14

For the combined neurological disorders, age-standardised DALY rates were significantly higher in males than in females (male-to-female ratio 1·12 [1·05-1·20]), but migraine, multiple sclerosis, and tension-type headache were more common and caused more burden in females, with male-to-female ratios of less than 0·7. 1 key finding →

Evidence: low

Full summary, score breakdown and related studies → Original source

The interaction between circadian syndrome and genetic susceptibility in the risk of incident dementia: A longitudinal cohort study

✓ Peer-reviewed alzhub usefulness score 44 out of 100. The Journal of Prevention of Alzheimer s Disease 2025-02-07

• CircS was associated with a 40.1 % increased risk of incident all-cause dementia. • A graded increase in dementia risk with escalating severity of CircS. • The presence of ≥ 3 CircS components was significantly associated with dementia. • There was a synergistic effect of CircS and high genetic risk on dementia. 5 key findings →

Evidence: moderate

Full summary, score breakdown and related studies → Original source Free full text

Trends and forecasts of the prevalence and mortality of Alzheimer’s disease and other dementias in China

✓ Peer-reviewed alzhub usefulness score 43 out of 100. Frontiers in Public Health 2025-07-22

In 2021, the age-standardized prevalence of AD and other dementia in China was 1,194 per 100,000 (95% CI: 1018-1,383), and the mortality rate was 35 per 100,000 (95% CI: 9-93). 5 key findings →

Evidence: moderate

Full summary, score breakdown and related studies → Original source Free full text

Global trends in prevalence, disability adjusted life years, and risk factors for early onset dementia from 1990 to 2021

✓ Peer-reviewed alzhub usefulness score 43 out of 100. Scientific Reports 2025-04-18

This study aims to analyze temporal trends in the prevalence and disability-adjusted life year (DALY) burden of early-onset dementia (EOD) globally from 1990 to 2021 and assess the attributable burdens of modifiable risk factors. 2 key findings →

Evidence: low

Full summary, score breakdown and related studies → Original source Free full text

Knowledge and attitudes about dementia and dementia genetics in a cohort of geriatric clinic attendees in Nigeria

✓ Peer-reviewed alzhub usefulness score 43 out of 100. Journal of Alzheimer s Disease 2025-04-22

BackgroundPopulation ageing in Africa will increase the burden of Alzheimer's disease and related dementias within the next few decades. 1 key finding →

Participants: 42 Evidence: low

Full summary, score breakdown and related studies → Original source Full text may need a subscription

Regional differences in the incidence of Alzheimer’s disease and related dementias in South Carolina

✓ Peer-reviewed alzhub usefulness score 43 out of 100. Frontiers in Neurology 2025-09-05

Regional differences in the incidence of ADRD suggest possible disparities in healthcare access, socioeconomic conditions and geographical factors. 2 key findings →

Participants: 18,955 Evidence: low

Full summary, score breakdown and related studies → Original source Free full text

Autism and Dementia: A Summative Report from the 2nd International Summit on Intellectual Disabilities and Dementia

✓ Peer-reviewed alzhub usefulness score 43 out of 100. Journal of Autism and Developmental Disorders 2025-05-06

This article synthesizes findings, from the Autism/Dementia Work Group of the 2nd International Summit on Intellectual Disabilities and Dementia, on the nature of autism/autism spectrum disorder and later-age neuropathologies, particularly dementia. 2 key findings →

Evidence: low

Full summary, score breakdown and related studies → Original source Free full text

Predicting dementia in people with Parkinson’s disease

✓ Peer-reviewed alzhub usefulness score 42 out of 100. npj Parkinson s Disease 2025-05-13

Parkinson's disease (PD) exhibits a variety of symptoms, with approximately 25% of patients experiencing mild cognitive impairment and 45% developing dementia within ten years of diagnosis. 2 key findings →

Evidence: moderate

Full summary, score breakdown and related studies → Original source Free full text

Estimating the impact of risk factor reduction on dementia prevalence in New Zealand

✓ Peer-reviewed alzhub usefulness score 42 out of 100. Alzheimer s & Dementia 2025-07-01

The PIF for the total NZ population following a 15% risk factor reduction was 14.6% (95% confidence interval: 7.7-21.1) Modeled projections demonstrated prevalence reduction over time, from 1.0% at 10 years to 4.2% at 30 years. 5 key findings →

Evidence: low

Full summary, score breakdown and related studies → Original source Free full text

The current status, trends, and challenges of Alzheimer’s disease and other dementias in Asia (1990–2036)

✓ Peer-reviewed alzhub usefulness score 42 out of 100. Frontiers in Public Health 2025-06-10

In 2021, Asia experienced a 250.44% increase in prevalent cases, a 297.34% rise in mortality, and a 249.54% surge in DALYs for AD and other dementias compared to 1990. 5 key findings →

Evidence: low

Full summary, score breakdown and related studies → Original source Free full text

Association of vitamin B12 deficiency in a dementia cohort with hippocampal atrophy on MRI

✓ Peer-reviewed alzhub usefulness score 41 out of 100. The Journal of Prevention of Alzheimer s Disease 2025-07-17

• This analysis consists of 567 participants revealed that vitamin B12 deficiency, not folate or vitamin B1 deficiency was associated with hippocampal atrophy detected by MRI-VSRAD analysis. • Vitamin B12 deficiency was associated with hyperhomocysteinemia. • Clear correlations were observed between hippocampal atrophy and vitamin B12 value. 4 key findings →

Participants: 323 Evidence: low

Full summary, score breakdown and related studies → Original source Free full text

Dementia prevalence within the Kingdom of Saudi Arabia National Guard Health System (2015–2023): An exploratory epidemiological study

✓ Peer-reviewed alzhub usefulness score 41 out of 100. Journal of Alzheimer s Disease 2025-02-17

BackgroundDementia is recognized as one of the prevalent neurocognitive disorders among older adults in Saudi Arabia, yet research efforts on its prevalence remains limited and fragmented, making it difficult to gain a full understanding of its epidemiology. 1 key finding →

Evidence: moderate

Full summary, score breakdown and related studies → Original source Full text may need a subscription

Critical appraisal of the health research literature: prevalence or incidence of a health problem

✓ Peer-reviewed alzhub usefulness score 40 out of 100. Chronic diseases in Canada 1998-01-01

This article identifies and discusses criteria that can be used by health professionals to critically appraise research articles that estimate the prevalence or incidence of a disease or health problem. 1 key finding →

Evidence: low

Full summary, score breakdown and related studies → Original source Full text may need a subscription

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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