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54/100

✓ Peer-reviewed alzhub usefulness score 54 out of 100. Risk factors

Topic: Risk, prevention and care in population studies

- Cognition was assessed with the Ruff Figural Fluency Test (RFFT), measuring non-verbal fluency and executive functioning. Cognitive decline was calculated by subtracting the RFFT sum score at baseline from the 10-year follow-up score. - Chronotype was associated with cognitive decline. Educational attainment, but not age or sex, moderated the relationship. No significant associations were observed in the low- (0.07, 95 % CI: -0.44, 0.57) or middle- (-0.41, 95 % CI: -0.88, 0.06) educational groups. In the high-educational group each one-hour increase in chronotype corresponded to a 0.80-point decline in cognition per decade (95 % CI: -1.34, -0.26). In this group, sleep quality and current smoking mediated 13.52 % and 18.64 % of the association, respectively. - Chronotype was associated with greater decline in non-verbal fluency and executive functioning among higher educated participants, highlighting the importance of targeted prevention strategies. FUNDING: - This work is part of the BIRD-NL consortium funded by the Dutch Medical Research Council, ZonMw (Dementia research program) project number:10,510,032,120,005.

Key findings

- Cognition was assessed with the Ruff Figural Fluency Test (RFFT), measuring non-verbal fluency and executive functioning.
Cognitive decline was calculated by subtracting the RFFT sum score at baseline from the 10-year follow-up score. - Chronotype was associated with cognitive decline.
Educational attainment, but not age or sex, moderated the relationship.
No significant associations were observed in the low- (0.07, 95 % CI: -0.44, 0.57) or middle- (-0.41, 95 % CI: -0.88, 0.06) educational groups.
In the high-educational group each one-hour increase in chronotype corresponded to a 0.80-point decline in cognition per decade (95 % CI: -1.34, -0.26).

Why it matters

In this cohort, chronotype was linked to greater decline in non-verbal fluency and executive functioning only among higher educated participants, with sleep quality and current smoking mediating part of that link. No significant associations were seen in the low- or middle-education groups, so this does not establish that changing sleep or smoking prevents cognitive decline.

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Study details

Study designcohort study
Participants23,798
Evidence strengthModerate

How this study scored 54/100

Published in a peer-reviewed journal, and it is a cohort study following people over time. Scored zero for effect reported and randomised / blinded because the record does not state it.

Component	Points	Why
Journal tier	7 / 10	Tier 3 — peer-reviewed journal (The Journal of Prevention of Alzheimer s Disease)
Journal's citation record	0 / 4	The Journal of Prevention of Alzheimer s Disease: journal h-index 63 (OpenAlex, 2026-10-29)
Study design	7 / 12	A cohort study following 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	4 / 4	23,798 participants
Effect reported	0 / 3	No effect size reported — scores zero (not stated in the record — scored 0)
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 Nynke Smidt: h-index 43 (OpenAlex, whole career)
Institution's track record	1 / 3	University of Groningen: institution h-index 1,383 (OpenAlex)
Multi-centre collaboration	2 / 3	OpenAlex lists 5 institution(s) in 1 country
Indexed in PubMed	2 / 2	Indexed in PubMed (PMID 40221238)
Free to read	2 / 2	Free to read
Total	54 / 100	—

What each of these 20 components measures, and what this score is not →

Read the original

Full text: free to read — OpenAlex lists this copy as free to read: the link above (checked 6 Feb 1020).

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. Check the citation against the original before you use it.

APA 7th

Wenzler, A. N., Liefbroer, A. C., Voshaar, R. C. O., & Smidt, N. (2025). Chronotype as a potential risk factor for cognitive decline: The mediating role of sleep quality and health behaviours in a 10-year follow-up study. The Journal of Prevention of Alzheimer s Disease. https://doi.org/10.1016/j.tjpad.2025.100168

Vancouver

Wenzler AN, Liefbroer AC, Voshaar RCO, Smidt N. Chronotype as a potential risk factor for cognitive decline: The mediating role of sleep quality and health behaviours in a 10-year follow-up study. The Journal of Prevention of Alzheimer s Disease. 2025. doi:10.1016/j.tjpad.2025.100168. PMID: 40221238.

BibTeX

@article{wenzler2025-40221238,
  author  = {Wenzler, Ana Neeltje and Liefbroer, Aart Cornelis and Voshaar, Richard C. Oude and Smidt, Nynke},
  title   = {{Chronotype as a potential risk factor for cognitive decline: The mediating role of sleep quality and health behaviours in a 10-year follow-up study}},
  journal = {The Journal of Prevention of Alzheimer s Disease},
  year    = {2025},
  doi     = {10.1016/j.tjpad.2025.100168},
  pmid    = {40221238},
  url     = {https://doi.org/10.1016/j.tjpad.2025.100168}
}

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