27,380 Alzheimer's and dementia studies in plain English, each scored out of 100.
Patients with AD spectrum demonstrated altered GM abundance, which was differentially mediated by countries and clinical stages. 5 key findings →
Design: systematic review Participants: 427 Evidence: high
Full summary, score breakdown and related studies → Original source
Limbic-predominant age-related TDP-43 encephalopathy neuropathologic change (LATE-NC) and Alzheimer's disease neuropathologic change (ADNC) are each associated with substantial cognitive impairment in aging populations. 2 key findings →
Design: longitudinal study Participants: 5,665 Evidence: moderate
Full summary, score breakdown and related studies → Original source
The chronological progression of brain atrophy over decades, from pre-symptomatic to dementia stages, has never been formally depicted in Alzheimer's disease. 2 key findings →
Design: cross-sectional Participants: 3,512 Evidence: moderate
Full summary, score breakdown and related studies → Original source
Eight observational studies were selected, carried out in humans and, therefore, suitable for inclusion in this review. 3 key findings →
Design: narrative review Evidence: low
Full summary, score breakdown and related studies → Original source
Brain regions with higher synaptic density are associated with a higher 18F-AV-1451 binding in progressive supranuclear palsy/corticobasal degeneration, but this association diminishes with disease severity. 1 key finding →
Design: cross-sectional Participants: 12 Evidence: moderate
Full summary, score breakdown and related studies → Original source Free full text
Parkinson's disease (PD) is the second most common degenerative disease of the central nervous system (CNS) after Alzheimer's disease. 2 key findings →
Design: cohort study Evidence: moderate
Full summary, score breakdown and related studies → Original source
Of 4,150 studies screened, 26 were eligible for inclusion, of which 17 were human studies, 8 were preclinical animal studies, and 1 included both human and preclinical animal studies. 4 key findings →
Design: narrative review Participants: 12 Evidence: low
Full summary, score breakdown and related studies → Original source Free full text
Eligibility to randomize into the A3 Trial or A45 Trial is based on the screening PET imaging results. 3 key findings →
Design: clinical trial Evidence: moderate
Full summary, score breakdown and related studies → Original source
Our data provide novel evidence that frontal lobe gamma activity is dampened in AD patients. 2 key findings →
Evidence: low
Full summary, score breakdown and related studies → Original source
Huntington's disease is a neurodegenerative disorder involving psychiatric, cognitive and motor symptoms. 2 key findings →
Evidence: low
Full summary, score breakdown and related studies → Original source
Synaptic dysfunction is an early mechanism in Alzheimer's disease that involves progressively larger areas of the brain over time. 1 key finding →
Evidence: low
Full summary, score breakdown and related studies → Original source
Cognitive dysfunctions such as mild cognitive impairment (MCI), Alzheimer's disease (AD), and other forms of dementia are recognized as common comorbidities of type 2 diabetes mellitus (T2DM). 1 key finding →
Evidence: low
Full summary, score breakdown and related studies → Original source
Lipopolysaccharide (LPS) is a cell-wall immunostimulatory endotoxin component of Gram-negative bacteria. 1 key finding →
Evidence: low
Full summary, score breakdown and related studies → Original source
Alzheimer's disease (AD) constitutes the most prominent form of dementia among elderly individuals worldwide. 5 key findings →
Evidence: low
Full summary, score breakdown and related studies → Original source
PBM treatment significantly improved the typical AD pathologies of memory loss, amyloid plaques, tau hyperphosphorylation, neuronal degeneration, spine damage, and synaptic loss. 5 key findings →
Evidence: low
Full summary, score breakdown and related studies → Original source
Alzheimer's disease (AD) was used to describe pre-senile dementia to differentiate it from senile dementia, which develops in the adult age group of more than 65 years. 5 key findings →
Design: narrative review Evidence: low
Full summary, score breakdown and related studies → Original source
The current nosological concept of α-synucleinopathies characterized by the presence of Lewy bodies (LBs) includes Parkinson's disease (PD), Parkinson's disease dementia (PDD), and dementia with Lewy bodies (DLB), for which the term "Lewy body disease" (LBD) has recently been proposed due to their considerable clinical and pathological overlap. 2 key findings →
Evidence: low
Full summary, score breakdown and related studies → Original source
It has been noticed in recent years that the unfavorable effects of the gut microbiota could exhaust host vigor and life, yet knowledge and theory are just beginning to be established. 3 key findings →
Evidence: low
Full summary, score breakdown and related studies → Original source
The highest density of microbes resides in human gastrointestinal tract, known as "Gut microbiome". 3 key findings →
Design: narrative review Evidence: low
Full summary, score breakdown and related studies → Original source
Astrocytes play key roles in the regulation of brain energy metabolism, which has a major impact on brain functions, including memory, neuroprotection, resistance to oxidative stress and homeostatic tone. 5 key findings →
Evidence: low
Full summary, score breakdown and related studies → Original source
Gut microbiota is emerging as a key regulator of many disease conditions and its dysregulation is implicated in the pathogenesis of several gastrointestinal and extraintestinal disorders. 5 key findings →
Design: narrative review Evidence: low
Full summary, score breakdown and related studies → Original source
Over the last 10 years, there has been a growing interest in the relationship between gut microbiota, the brain, and neurologic-associated affections. 1 key finding →
Evidence: low
Full summary, score breakdown and related studies → Original source
Short-chain fatty acids (SCFAs) are important metabolites derived from the gut microbiota through fermentation of dietary fiber. 1 key finding →
Evidence: low
Full summary, score breakdown and related studies → Original source
Synaptic abnormalities are a cardinal feature of Alzheimer's disease (AD) that are known to arise as the disease progresses. 1 key finding →
Evidence: low
Full summary, score breakdown and related studies → Original source
The oral cavity is the initial chamber of digestive tract; the saliva swallowed daily contains an estimated 1.5 × 1012 oral bacteria. 4 key findings →
Evidence: low
Full summary, score breakdown and related studies → Original source
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
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.
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.
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 →