Get help now — free helplines

You can call any of these for free. You do not need a diagnosis, an appointment, or a crisis to call — questions and plain exhaustion are reasons enough.

  • Alzheimer's Association 24/7 Helpline 800-272-3900 24 hours a day, 365 days a year Free, confidential support and information for people with dementia, caregivers, families and the public. Master's-level clinicians. Also Spanish.
  • 988 Suicide & Crisis Lifeline 988 24/7 Call or text 988, or chat at 988lifeline.org. For anyone in emotional distress or a mental-health crisis, including caregivers.
  • Alzheimer's Foundation of America (AFA) Helpline 866-232-8484 9:00 am - 9:00 pm ET, seven days a week Licensed social workers providing support, info and referrals. Also text message and web chat. Text: 646-586-5283

In a medical emergency, call 911. More numbers, and what each line does, on the help page.

Find studies

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.

Emerging evidence suggests that treatment with glucagon-like peptide-1 receptor agonists (GLP-1 RAs) could be an interesting treatment strategy to reduce neurological complications such as stroke, cognitive impairment, and peripheral neuropathy. 3 key findings →

Design: systematic review Participants: 19 Evidence: high

A total of seven studies were included. The forest plot results showed that taking lithium therapy reduced the risk of AD (RR 0.59, 95% confidence interval [CI]: 0.44-0.78) and is also protective in reducing the risk of dementia (RR 0.66, 95% CI: 0.56-0.77). 4 key findings →

Design: meta-analysis Evidence: high

Sleep disorders, particularly insomnia and obstructive sleep apnea, are increasingly implicated as significant contributors to cognitive decline, dementia, and neurodegenerative diseases such as Alzheimer's disease (AD) and vascular cognitive impairment and dementia (VCID). 4 key findings →

Design: meta-analysis Evidence: high

Sleep Disorders and Cognitive Dysfunctions in Parkinson's Disease: A Meta-Analytic Study

✓ Peer-reviewed alzhub usefulness score 77 out of 100. Neuropsychology review 2021-03-29

A relationship between sleep disorders and cognitive dysfunctions was reported in Parkinson's Disease (PD), however, some studies did not confirm the link. 4 key findings →

Design: meta-analysis Participants: 54 Evidence: high

Alzheimer's disease (AD) is projected to become the highest-burden neurological disorder globally. 1 key finding →

Design: meta-analysis Evidence: high

This large review pooled 113 studies (nearly 30,000 people) comparing different forms of blood phosphorylated tau for detecting Alzheimer's pathology. p-tau217 was clearly the best-performing marker, correctly identifying disease pathology about 88% of the time, outperforming other tau variants like p-tau181. 4 key findings →

Design: meta-analysis Participants: 29,625 Evidence: moderate

Pooling data on over 2.3 million people worldwide, this analysis confirmed that type 2 diabetes raises dementia risk by roughly 60% in both men and women, but the excess risk of vascular dementia specifically was notably higher in women than men. 4 key findings →

Design: meta-analysis Participants: 2,310,330 Evidence: high

Synthesis methods We meta-analysed results for each outcome within each comparison using the inverse variance method and the random-effects model. 5 key findings →

Design: meta-analysis Participants: 20,342 Evidence: high

Systematic meta-analyses of Alzheimer disease genetic association studies: the AlzGene database

✓ Peer-reviewed alzhub usefulness score 76 out of 100. Nature genetics 2007-01-01

The past decade has witnessed hundreds of reports declaring or refuting genetic association with putative Alzheimer disease susceptibility genes. 1 key finding →

Design: meta-analysis Evidence: high

A large fraction of dementia cases in the US were associated with potentially modifiable risk factors, especially for Black and Hispanic individuals. 4 key findings →

Design: systematic review Evidence: high

Dementia has been increasingly more recognized to be a common feature in patients with Parkinson's disease (PD), especially in old age. 4 key findings →

Design: systematic review Evidence: high

We did not apply any language or date restrictions to the electronic searches, and we did not use any methodological filters as a method to restrict the search overall. 3 key findings →

Design: meta-analysis Participants: 70 Evidence: high

Observational epidemiological studies have shown a positive association between hypertension and risk of incident dementia; however, the effects of antihypertensive therapy on cognitive function in controlled trials have been conflicting, and meta-analyses of the trials have not provided clear evidence of whether antihypertensive treatment reduces dementia incidence. 5 key findings →

Design: meta-analysis Participants: 1,687 Evidence: high

Sex Differences in Longitudinal Tau-PET in Preclinical Alzheimer Disease: A Meta-Analysis

✓ Peer-reviewed alzhub usefulness score 76 out of 100. JAMA neurology 2025-03-03

Mounting evidence in adults without AD indicates that females exhibit higher tau deposition than age-matched males, particularly in the setting of elevated β-amyloid (Aβ), but the evidence for sex differences in tau accumulation rates is inconclusive. 5 key findings →

Design: meta-analysis Participants: 1,376 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

Cognitive impairment is a central non-motor symptom of Parkinson's disease (PD), and there are no established treatments. 4 key findings →

Design: meta-analysis Participants: 679 Evidence: high

Question Does physical exercise training improve physical function and quality of life in people with cognitive impairment and dementia? 4 key findings →

Design: systematic review Participants: 3,988 Evidence: high

Studies implementing research methods (30 studies) demonstrated the role of family members as both proxy decision-makers and supporting decision-making for the person with impaired capacity. 2 key findings →

Design: systematic review Participants: 19 Evidence: high

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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 27,780 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 27,780 records, built mostly from automated pulls of Europe PMC (61.1% of the library) and OpenAlex (18.3%), 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