- 967studies in the library match, of 29,380
- 493name it in the title
- 1982–2026years published
- 923peer-reviewed articles
The query: title or abstract mentions "sleep", "insomnia", "apnoea/apnea", "circadian", "sundowning", "melatonin" or "hypnotic", matched case-insensitively against each record's title and abstract (its summary field) in alzhub's library of 29,380 study records, as of 2026-11-08. Every count on this page comes from that match. The matched list as JSON.
During sleep the brain clears waste proteins, including amyloid-beta, and lab and imaging studies have asked whether short or fragmented sleep lets amyloid and tau build up. Cohort studies follow sleep duration, insomnia and obstructive sleep apnoea against later dementia. In people who already have dementia, sleep disturbance and sundowning are common and hard on caregivers, and some sleep medicines carry their own risks in older people.
This page describes what published research in alzhub's library reports. It is not medical advice and does not apply to any one person: a doctor who knows the person's history is the only one who can say what a result or a treatment means for them.
What the studies report, in their own words
Whole sentences copied from the abstract or key findings of the highest-scoring matched studies, chosen because they mention the subject and give a figure. 8 of the 967 matched records are quoted; each links to its study page and from there to the paper.
“Individuals with poor sleep quality exhibited greater PET Aβ burden and higher Aβ42 levels in plasma than those with good sleep quality.”
“Individuals with sleep problems had a 1.55 (95% CI: 1.25-1.93), 1.65 (95% CI: 1.45-1.86), and 3.78 (95% CI: 2.27-6.30) times higher risk of AD, cognitive impairment, and preclinical AD than individuals without sleep problems, respectively.”
“Melatonin was associated with a lower risk of delirium (12.0% vs.”
“Thirty-nine cohort studies were included, with subgroup analyses showing significant associations between all-cause dementia and obstructive sleep apnea (HR 1.33, 95% CI 1.09-1.61), insomnia (HR 1.36, 95% CI 1.19-1.55), and other sleep disorders (HR 1.33, 95% CI 1.24-1.43).”
“MR analyses supported a causal link between genetically predicted insomnia and increased stroke risk (OR 1.31, 95% CI 1.13-1.51, p = 0.00072), but not with dementia or SVD markers.”
“Baseline sleep disturbance was associated with a faster rate of longitudinal CSF Aβ42 decline.”
“Melatonin had no effect on median total time asleep (n=25, z=1.35, p=0.18), number of awakenings (n=25, z=0.32, p=0.75) or sleep efficiency (n=25, z=0.17, p=0.24).”
“SECONDARY antipsychotics, antidepressants, hypnotics, antiepileptics, short-session ( ≤ 30 minutes), long-session ( ≥ 45 minutes), and family/group psychotherapy.”
What kind of evidence it is
By study design
| Design (as recorded) | Studies |
|---|---|
| Systematic review or meta-analysis | 62 |
| Randomised controlled trial | 18 |
| Other clinical trial | 2 |
| Cohort or longitudinal study | 121 |
| Case-control study | 12 |
| Cross-sectional study | 62 |
| Other recorded design | 9 |
| No design recorded | 681 |
The design is the one named in alzhub's record for the study; a record with none is counted as "no design recorded".
By year
| Year | Studies | Share |
|---|---|---|
| 2026 | 90 | |
| 2025 | 148 | |
| 2024 | 43 | |
| 2023 | 48 | |
| 2022 | 46 | |
| 2021 | 52 | |
| 2020 | 58 | |
| 2019 | 41 | |
| 2018 | 36 | |
| 2017 | 32 | |
| 2016 and earlier | 373 |
Other counts within the matched set
| Peer-reviewed articles | 923 |
| Marked open access in the record | 295 |
| Rated "high" evidence strength in alzhub's summary | 140 |
| Rated "moderate" evidence strength in alzhub's summary | 197 |
| Rated "low" evidence strength in alzhub's summary | 625 |
| No evidence-strength rating | 5 |
| Records stating a participant count | 342 |
| Median participants (those records) | 148 |
| Largest participant count | 1,913,945 |
Within the 967 matched studies
| Studies… | Count | Rule |
|---|---|---|
| …that mention sleep apnoea | 113 | the abstract also contains "apnoea" or "apnea" |
| …that mention amyloid or tau | 168 | the abstract also contains "amyloid" or "tau" |
| …that mention a sleep medicine (hypnotic, benzodiazepine, melatonin, zolpidem) | 103 | the abstract also contains "hypnotic", "benzodiazepine", "melatonin", "zolpidem" or "z-drug" |
The 10 highest-scoring matched studies
Title matches first, then by alzhub's usefulness score, which rates a study's design, journal, evidence and recency, not whether its result is good news.
- Polysomnographic assessment of suvorexant in patients with probable Alzheimer's disease dementia and insomnia: a randomized trial
- Sleep Architecture, Obstructive Sleep Apnea, and Cognitive Function in Adults
- Associations among sleep quality, sleep duration, and Alzheimer's disease biomarkers: A systematic review and meta-analysis
- A Focused Update to the Clinical Practice Guidelines for the Prevention and Management of Pain, Anxiety, Agitation/Sedation, Delirium, Immobility, and Sleep Disruption in Adult Patients in the ICU
- Sleep disturbances increase the risk of dementia: A systematic review and meta-analysis
- Sleep, Cognitive impairment, and Alzheimer's disease: A Systematic Review and Meta-Analysis
- Melatonin decreases delirium in elderly patients: a randomized, placebo-controlled trial
- Sleep disorders increase the risk of dementia, Alzheimer's disease, and cognitive decline: a meta-analysis
- Sleep Disorders and Cognitive Dysfunctions in Parkinson's Disease: A Meta-Analytic Study
- Sleep Characteristics and Risk of Stroke and Dementia: An Observational and Mendelian Randomization Study
Systematic reviews and meta-analyses in the set
62 of the matched records are recorded as a systematic review, meta-analysis or umbrella review; the highest-scoring not already listed above:
- Mental and neurological disorders and risk of COVID-19 susceptibility, illness severity and mortality: A systematic review, meta-analysis and call for action
- Genome-wide association study of idiopathic hypersomnia in a Japanese population
- Potentially Modifiable Risk Factors for Dementia and Mild Cognitive Impairment: An Umbrella Review and Meta-Analysis
- Cannabis in Palliative Care: A Systematic Review of Current Evidence
- Efficacy and adverse effects of cholinesterase inhibitors and memantine in vascular dementia: a meta-analysis of randomised controlled trials
Newest matched studies
- Endocannabinnoids innervate Circadian mechinary mitigating neuroinflammation, amyloidogenesis and cognition phenotypic to AD
- Beyond Glycemic Control: The Pleiotropic Role of GLP-1RAs and Melatonin in Combating Neuroinflammation and Mitochondrial Dysfunction
- Genetic susceptibility to Lewy body disease and the distribution of Lewy pathology
- Stable and Interpretable Cognitive Status Screening Using Longitudinal Wearable Data
- Progressive neurodegeneration of the locus coeruleus drives rapid eye movement sleep fragmentation
Journals with the most matched studies
| Journal | Studies |
|---|---|
| Neurology | 37 |
| Alzheimer's & dementia : the journal of the Alzheimer's Association | 22 |
| Sleep | 21 |
| The Lancet. Neurology | 20 |
| Annals of neurology | 18 |
Questions
- Does poor sleep cause Alzheimer's?
- The studies below report associations between short or disrupted sleep and later dementia or amyloid build-up, and some mechanisms for it; whether improving sleep lowers risk is a separate question that fewer studies have tested directly.
- How many studies on sleep and alzheimer's does alzhub hold?
- 967 of the 29,380 study records in alzhub's library match the query "title or abstract mentions "sleep", "insomnia", "apnoea/apnea", "circadian", "sundowning", "melatonin" or "hypnotic""; 493 of them name it in the title. Counted from the records when this page was built.
- What kinds of study are they?
- 62 systematic review or meta-analysis, 18 randomised controlled trials, 2 other clinical trials, 121 cohort or longitudinal studys, 12 case-control studys, 62 cross-sectional studys; 681 record no design.
- What is the most recent study in the set?
- "Endocannabinnoids innervate Circadian mechinary mitigating neuroinflammation, amyloidogenesis and cognition phenotypic to AD" (Authorea Preprints, 2026), the newest by publication date among the matched records.
- Which journals publish most on it?
- Neurology (37); Alzheimer's & dementia : the journal of the Alzheimer's Association (22); Sleep (21), counted across the matched records.
Read on
- Risk factors, rankedWhere sleep sits among the known risk factors.
- Daily careSundowning and night-time care, in plain language.
- PreventionLifestyle trials and their results.