27,380 Alzheimer's and dementia studies in plain English, each scored out of 100.
Mild cognitive impairment (MCI) in Parkinson's disease (PD) may be associated with subtle functional impairment and worse quality of life. 4 key findings →
Participants: 28 Evidence: high
Full summary, score breakdown and related studies → Original source
Sertraline did not demonstrate efficacy for the treatment depression symptoms in patients with AD. 2 key findings →
Participants: 67 Evidence: high
Full summary, score breakdown and related studies → Original source Free full text
As none of the studies exceeded a duration of 6 months, the recommendations given are for the short-term management of the different non-motor symptoms. 5 key findings →
Design: randomized controlled trial Evidence: high
Full summary, score breakdown and related studies → Original source Free full text
Dementia with Lewy bodies and Parkinson's disease dementia, jointly known as Lewy body dementia, are common neurodegenerative conditions. 5 key findings →
Design: meta-analysis Evidence: high
Full summary, score breakdown and related studies → Original source Free full text
The use of APs by patients with dementia in the general population is associated with increased mortality, but whether this risk extends to patients with PD remains unknown. 5 key findings →
Design: cohort study Participants: 7,877 Evidence: moderate
Full summary, score breakdown and related studies → Original source
In multivariate analyses, baseline age, University of Pennsylvania Smell Inventory Test (UPSIT) scores, CSF amyloid - (Aβ 42 ) to t-tau ratio, and APOE status were associated with change in MoCA scores over time. 5 key findings →
Design: cohort study Participants: 390 Evidence: moderate
Full summary, score breakdown and related studies → Original source Free full text
These samples were graded on an ordinal scale and genotyped for variants associated with synucleinopathies. 2 key findings →
Participants: 213 Evidence: moderate
Full summary, score breakdown and related studies → Original source Free full text
The Dementia with Lewy Bodies (DLB) Consortium has refined its recommendations about the clinical and pathologic diagnosis of DLB, updating the previous report, which has been in widespread use for the last decade. 5 key findings →
Evidence: high
Full summary, score breakdown and related studies → Original source Free full text
The Montreal Cognitive Assessment, but not the Mini-Mental State Examination, has adequate psychometric properties as a screening instrument for the detection of mild cognitive impairment or dementia in Parkinson disease. 3 key findings →
Participants: 132 Evidence: low
Full summary, score breakdown and related studies → Original source Free full text
The evidence base for treating a range of nonmotor symptoms in PD has grown substantially in recent years. 2 key findings →
Participants: 37 Evidence: high
Full summary, score breakdown and related studies → Original source Free full text
GBA mutations (β = 4.65; 95% CI, 1.72-7.58; P = .002), E326K (β = 3.42; 95% CI, 0.66-6.17; P = .02), and GBA variants combined as a single group (β = 4.01; 95% CI, 1.95-6.07; P = 1.5 × 10-4) were associated with a more rapid decline in MDS-UPDRS III score. 4 key findings →
Design: longitudinal study Participants: 740 Evidence: moderate
Full summary, score breakdown and related studies → Original source Free full text
Dementia is a frequent problem encountered in advanced stages of Parkinson disease (PD). 5 key findings →
Design: longitudinal study Evidence: moderate
Full summary, score breakdown and related studies → Original source Free full text
MCI is common in patients with PD without dementia, affecting a range of cognitive domains, including memory, visual-spatial, and attention/executive abilities. 2 key findings →
Participants: 1,346 Evidence: moderate
Full summary, score breakdown and related studies → Original source Free full text
Cognitive decline associated with Parkinson disease (PD) is common and highly disabling. 4 key findings →
Design: cohort study Participants: 45 Evidence: moderate
Full summary, score breakdown and related studies → Original source Free full text
Parkinson disease (PD) is the second most common neurodegenerative disorder, affecting >1% of the population ≥65 years of age and with a prevalence set to double by 2030. 5 key findings →
Evidence: low
Full summary, score breakdown and related studies → Original source Free full text
Mild cognitive impairment is common in nondemented Parkinson's disease (PD) patients and may be a harbinger of dementia. 1 key finding →
Evidence: low
Full summary, score breakdown and related studies → Original source Free full text
Our data indicate that the APOE ε4 allele is an important predictor of cognitive function in PD across multiple domains. 5 key findings →
Participants: 1,079 Evidence: low
Full summary, score breakdown and related studies → Original source Free full text
LBD patients with AD copathology harbor greater neocortical SYN pathology. 1 key finding →
Participants: 36 Evidence: moderate
Full summary, score breakdown and related studies → Original source Free full text
Loss-of-function mutations in the GBA gene are associated with more severe cognitive impairment in PD, but the nature of these deficits is not well understood and whether common GBA polymorphisms influence cognitive performance in PD is not yet known. 4 key findings →
Participants: 60 Evidence: low
Full summary, score breakdown and related studies → Original source Free full text
Plasma NfL is a useful prognostic biomarker for PD, predicting clinical conversion to mild cognitive impairment or dementia. © 2021 International Parkinson and Movement Disorder Society. 1 key finding →
Design: cross-sectional Evidence: moderate
Full summary, score breakdown and related studies → Original source
Baseline data of 423 PD patients and 196 HCs yielded no between-group differences in demographic characteristics. 3 key findings →
Evidence: moderate
Full summary, score breakdown and related studies → Original source Free full text
At baseline, worse olfaction (lowest tertile) was associated with more severe NMS, including anxiety and autonomic symptoms. 2 key findings →
Design: cross-sectional Evidence: moderate
Full summary, score breakdown and related studies → Original source Free full text
These findings confirm that MCI is associated with widespread cortical atrophy. 5 key findings →
Evidence: moderate
Full summary, score breakdown and related studies → Original source Free full text
The most frequent NPS were depression (in 66% of the sample), anxiety (65%) and mental fatigue (57%). 3 key findings →
Participants: 94 Evidence: low
Full summary, score breakdown and related studies → Original source Free full text
The ability of Alzheimer's disease (AD) cerebrospinal fluid (CSF) biomarkers (amyloid β peptide 1-42, total tau, and phosphorylated tau) to discriminate AD from related disorders is limited. 4 key findings →
Participants: 367 Evidence: low
Full summary, score breakdown and related studies → Original source Free full text
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 →