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66/100

✓ Peer-reviewed alzhub usefulness score 66 out of 100. Prevention and risk

Reviewed as evidence on: Vitamin D supplementation and cognitive score 4 studies (what the news said). Being listed means the study bears on the question, not that it agrees with the news.

Topic: Risk, prevention and care in population studies

Background To our knowledge, no prospective study has examined the association between vitamin D and cognitive decline or dementia. Methods We determined whether low levels of serum 25-hydroxyvitamin D (25[OH]D) were associated with an increased risk of substantial cognitive decline in the InCHIANTI population-based study conducted in Italy between 1998 and 2006 with follow-up assessments every 3 years. A total of 858 adults 65 years or older completed interviews, cognitive assessments, and medical examinations and provided blood samples. Cognitive decline was assessed using the Mini-Mental State Examination (MMSE), and substantial decline was defined as 3 or more points. The Trail-Making Tests A and B were also used, and substantial decline was defined as the worst 10% of the distribution of decline or as discontinued testing. Results The multivariate adjusted relative risk (95% confidence interval [CI]) of substantial cognitive decline on the MMSE in participants who were severely serum 25(OH)D deficient (levels /=75 nmol/L) was 1.60 (95% CI, 1.19-2.00). Multivariate adjusted random-effects models demonstrated that the scores of participants who were severely 25(OH)D deficient declined by an additional 0.3 MMSE points per year more than those with sufficient levels of 25(OH)D. The relative risk for substantial decline on Trail-Making Test B was 1.31 (95% CI, 1.03-1.51) among those who were severely 25(OH)D deficient compared with those with sufficient levels of 25(OH)D. No significant association was observed for Trail-Making Test A. Conclusion Low levels of vitamin D were associated with substantial cognitive decline in the elderly population studied over a 6-year period, which raises important new possibilities for treatment and prevention.

Cite this study APA, Vancouver, BibTeX · download .bib or .ris

APA 7th

Llewellyn, D. J., Lang, I. A., Langa, K. M., Muniz-Terrera, G., Phillips, C. L., Cherubini, A., et al. (2010). Vitamin D and risk of cognitive decline in elderly persons. Archives of internal medicine. https://doi.org/10.1001/archinternmed.2010.173

Vancouver

Llewellyn DJ, Lang IA, Langa KM, Muniz-Terrera G, Phillips CL, Cherubini A, et al. Vitamin D and risk of cognitive decline in elderly persons. Archives of internal medicine. 2010. doi:10.1001/archinternmed.2010.173. PMID: 20625021.

BibTeX

@article{llewellyn2010-20625021,
  author  = {Llewellyn, D. J. and Lang, I. A. and Langa, K. M. and Muniz-Terrera, G. and Phillips, C. L. and Cherubini, A. and Ferrucci, L. and Melzer, D.},
  title   = {{Vitamin D and risk of cognitive decline in elderly persons}},
  journal = {Archives of internal medicine},
  year    = {2010},
  doi     = {10.1001/archinternmed.2010.173},
  pmid    = {20625021},
  url     = {https://doi.org/10.1001/archinternmed.2010.173}
}

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.

Key findings

Methods We determined whether low levels of serum 25-hydroxyvitamin D (25[OH]D) were associated with an increased risk of substantial cognitive decline in the InCHIANTI population-based study conducted in Italy between 1998 and 2006 with follow-up assessments every 3 years.
Results The multivariate adjusted relative risk (95% confidence interval [CI]) of substantial cognitive decline on the MMSE in participants who were severely serum 25(OH)D deficient (levels /=75 nmol/L) was 1.60 (95% CI, 1.19-2.00).
Multivariate adjusted random-effects models demonstrated that the scores of participants who were severely 25(OH)D deficient declined by an additional 0.3 MMSE points per year more than those with sufficient levels of 25(OH)D.
The relative risk for substantial decline on Trail-Making Test B was 1.31 (95% CI, 1.03-1.51) among those who were severely 25(OH)D deficient compared with those with sufficient levels of 25(OH)D.
No significant association was observed for Trail-Making Test A.

Why it matters

In this population-based study, severely vitamin D deficient participants had a higher relative risk of substantial cognitive decline on the Mini-Mental State Examination compared with those with sufficient levels. Their scores declined by an additional 0.3 MMSE points per year more than those with sufficient levels.

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Study details

Participants858
Evidence strengthLow

How this study scored 66/100

Published in a peer-reviewed journal, and it is a randomized controlled trial. Scored zero for effect reported because the record does not state it.

Component	Points	Why
Journal tier	7 / 10	Tier 3 — peer-reviewed journal (Archives of internal medicine)
Journal's citation record	3 / 4	Archives of Internal Medicine: journal h-index 462 (OpenAlex, 2026-10-29)
Study design	11 / 12	A randomized controlled trial (from PubMed type “Randomized Controlled Trial”)
Strength of evidence	1 / 5	Rated “low” in our summary
Peer-review validation	10 / 10	Peer-reviewed. Published as an article in a named peer-reviewed journal.
How recent	1 / 5	2010 — within 20 year(s) of the newest study here
Sample size	2 / 4	858 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)
Randomized / blinded	1 / 2	Randomized (as stated in the record)
Times cited	6 / 7	Cited 460 times (OpenAlex, 2026-10-10)
Citations per year	4 / 5	25.6 citations a year over 18 year(s) since 2010
Impact for its field and year	5 / 6	Cited 29.5× the average for papers of its field and year (OpenAlex FWCI)
Cited by studies here	3 / 6	Cited by 10 other studies in this library
Still being cited	2 / 4	Cited 39 times in 2024–2026 (2026 still in progress; OpenAlex)
Senior author's track record	3 / 4	Last-listed author David J. Llewellyn: h-index 68 (OpenAlex, whole career)
Institution's track record	1 / 3	University of Exeter: institution h-index 905 (OpenAlex)
Multicenter collaboration	1 / 3	OpenAlex lists 2 institution(s) in 1 country
Indexed in PubMed	2 / 2	Indexed in PubMed (PMID 20625021)
Free to read	0 / 2	Behind a paywall — scores zero
Total	66 / 100	—

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