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Changes in sleep dimensions, cognitive transitions, and incident dementia: a two-cohort longitudinal study
Bingtao Weng, Haizhen Chen, Ying Zheng, Jiahe Wei, Pei Xue, Christian Benedict, Wei Chen, Xiao Wei Tan. SLEEP, 2025-08-09
Topic: Risk, prevention and care in population studies
A total of 8994 and 14 720 participants were involved in the change-to-change analyses and change-to-dementia analyses, respectively. Compared to individuals who maintained their original sleep dimensions, those who changed their sleep duration to the optimal range (7-8 h/day) or shifted chronotype to morningness exhibited higher overall cognitive scores (β = 0.15, p = .037; β = 0.23, p = .011). Conversely, transitioning to non-optimal sleep duration (OR = 1.07, p = .034) or declining overall sleep quality (OR = 1.06, p = .006) increased the risk of cognitive decline from normal baseline. Napping cessation increased the risk of MCI progression to dementia (OR = 1.16, p = .001). Transitioning to non-optimal sleep duration (HR = 1.82, p = .005) and discontinuing napping (HR = 2.13, p = .015) were associated with a higher incident of all-cause dementia. Maintaining optimal or optimizing sleep duration, preserving napping habits, and transitioning to a morning chronotype are essential for dementia prevention.
Key findings
- A total of 8994 and 14 720 participants were involved in the change-to-change analyses and change-to-dementia analyses, respectively.
- Compared to individuals who maintained their original sleep dimensions, those who changed their sleep duration to the optimal range (7-8 h/day) or shifted chronotype to morningness exhibited higher overall cognitive scores (β = 0.15, p = .037; β = 0.23, p = .011).
- Conversely, transitioning to non-optimal sleep duration (OR = 1.07, p = .034) or declining overall sleep quality (OR = 1.06, p = .006) increased the risk of cognitive decline from normal baseline.
- Napping cessation increased the risk of MCI progression to dementia (OR = 1.16, p = .001).
- Transitioning to non-optimal sleep duration (HR = 1.82, p = .005) and discontinuing napping (HR = 2.13, p = .015) were associated with a higher incident of all-cause dementia.
Why it matters
This longitudinal study found that shifting to optimal sleep duration or a morning chronotype was linked to higher cognitive scores, while moving to non-optimal sleep or stopping napping was linked to higher dementia risk. It suggests maintaining healthy sleep habits may help prevent dementia, but it is observational and cannot prove cause and effect.
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Study details
- Study designlongitudinal study
- Participants720
- Effect sizeOR = 1.07; OR = 1.06; OR = 1.16
- Evidence strengthModerate
How this study scored 55/100
Published in a peer-reviewed journal, and it is a longitudinal study following the same people over time. Scored zero for randomised / blinded because the record does not state it.
| Component | Points | Why |
|---|---|---|
| Journal tier | 7 / 10 | Tier 3 — peer-reviewed journal (SLEEP) |
| Journal's citation record | 3 / 4 | SLEEP: journal h-index 308 (OpenAlex, 2026-10-29) |
| Study design | 7 / 12 | A longitudinal study following the same people over time |
| Strength of evidence | 3 / 5 | Rated “moderate” in our summary |
| Peer-review validation | 10 / 10 | Peer-reviewed. Published as an article in a named peer-reviewed journal. |
| How recent | 4 / 5 | 2025 — within 3 year(s) of the newest study here |
| Sample size | 2 / 4 | 720 participants |
| Effect reported | 3 / 3 | Effect reported with a statistic (interval, p-value, ratio or similar) |
| Studied in people | 3 / 3 | Studied in people (participant count stated) |
| Randomised / blinded | 0 / 2 | No randomisation or blinding stated — scores zero (not stated in the record — scored 0) |
| Times cited | 2 / 7 | Cited 5 times (OpenAlex, 2026-10-10) |
| Citations per year | 1 / 5 | 1.7 citations a year over 3 year(s) since 2025 |
| Impact for its field and year | 3 / 6 | Cited 5.3× the average for papers of its field and year (OpenAlex FWCI) |
| Cited by studies here | 0 / 6 | No other study in this library cites it |
| Still being cited | 1 / 4 | Cited 5 times in 2024–2026 (2026 still in progress; OpenAlex) |
| Senior author's track record | 2 / 4 | Last-listed author Xiao Wei Tan: h-index 37 (OpenAlex, whole career) |
| Institution's track record | 1 / 3 | Uppsala University: institution h-index 1,114 (OpenAlex) |
| Multi-centre collaboration | 1 / 3 | OpenAlex lists 3 institution(s) in 2 countries |
| Indexed in PubMed | 2 / 2 | Indexed in PubMed (PMID 40795941) |
| Free to read | 0 / 2 | Behind a paywall — scores zero |
| Total | 55 / 100 | — |
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Read the original
May need a subscription OpenAlex found no free copy of the full text (checked 6 Feb 1020), so the publisher may charge for it. The PubMed abstract is free.
Cite this study APA, Vancouver, BibTeX · download .bib or .ris
Built from the record alzhub holds for this paper, not looked up. Volume, issue and page numbers are not held in the record. The record names 8 authors; APA and Vancouver show the first six, BibTeX and the downloads carry all of them. Check the citation against the original before you use it.
APA 7th
Weng, B., Chen, H., Zheng, Y., Wei, J., Xue, P., Benedict, C., et al. (2025). Changes in sleep dimensions, cognitive transitions, and incident dementia: a two-cohort longitudinal study. SLEEP. https://doi.org/10.1093/sleep/zsaf233
Vancouver
Weng B, Chen H, Zheng Y, Wei J, Xue P, Benedict C, et al. Changes in sleep dimensions, cognitive transitions, and incident dementia: a two-cohort longitudinal study. SLEEP. 2025. doi:10.1093/sleep/zsaf233. PMID: 40795941.
BibTeX
@article{weng2025-40795941,
author = {Weng, Bingtao and Chen, Haizhen and Zheng, Ying and Wei, Jiahe and Xue, Pei and Benedict, Christian and Chen, Wei and Tan, Xiao Wei},
title = {{Changes in sleep dimensions, cognitive transitions, and incident dementia: a two-cohort longitudinal study}},
journal = {SLEEP},
year = {2025},
doi = {10.1093/sleep/zsaf233},
pmid = {40795941},
url = {https://doi.org/10.1093/sleep/zsaf233}
}
Studies this one cites
Referenced by this study and also in the alzhub library, so you can read them here.