Vitamin D and the risk of dementia and Alzheimer disease.

Abstract

OBJECTIVE:

To determine whether low vitamin D concentrations are associated with an increased risk of incident all-cause dementia and Alzheimer disease.

METHODS:

One thousand six hundred fifty-eight elderly ambulatory adults free from dementia, cardiovascular disease, and stroke who participated in the US population-based Cardiovascular Health Study between 1992-1993 and 1999 were included. Serum 25-hydroxyvitamin D (25(OH)D) concentrations were determined by liquid chromatography-tandem mass spectrometry from blood samples collected in 1992-1993. Incident all-cause dementia and Alzheimer disease status were assessed during follow-up using National Institute of Neurological and Communicative Disorders and Stroke/Alzheimer's Disease and Related Disorders Association criteria.

RESULTS:

During a mean follow-up of 5.6 years, 171 participants developed all-cause dementia, including 102 cases of Alzheimer disease. Using Cox proportional hazards models, the multivariate adjusted hazard ratios (95% confidence interval [CI]) for incident all-cause dementia in participants who were severely 25(OH)D deficient (<25 nmol/L) and deficient (≥25 to <50 nmol/L) were 2.25 (95% CI: 1.23-4.13) and 1.53 (95% CI: 1.06-2.21) compared to participants with sufficient concentrations (≥50 nmol/L). The multivariate adjusted hazard ratios for incident Alzheimer disease in participants who were severely 25(OH)D deficient and deficient compared to participants with sufficient concentrations were 2.22 (95% CI: 1.02-4.83) and 1.69 (95% CI: 1.06-2.69). In multivariate adjusted penalized smoothing spline plots, the risk of all-cause dementia and Alzheimer disease markedly increased below a threshold of 50 nmol/L.

CONCLUSION:

Our results confirm that vitamin D deficiency is associated with a substantially increased risk of all-cause dementia and Alzheimer disease. This adds to the ongoing debate about the role of vitamin D in nonskeletal conditions.

• Authors: Thomas J Littlejohns, William E Henley, Iain A Lang, Cedric Annweiler, Olivier Beauchet, Paulo H M Chaves, Linda Fried, Bryan R Kestenbaum, Lewis H Kuller, Kenneth M Langa, Oscar L Lopez, Katarina Kos, Maya Soni, David J Llewellyn
• Journal: Neurology (Neurology) Vol. 83 Issue 10 Pg. 920-8 (Sep 02 2014) ISSN: 1526-632X [Electronic] United States
• PMID: 25098535 (Publication Type: Journal Article, Research Support, N.I.H., Extramural, Research Support, Non-U.S. Gov't)
• Copyright: © 2014 American Academy of Neurology.

Chemical References

• Vitamin D
• 25-hydroxyvitamin D

Topics

• Aged
• Alzheimer Disease (blood, epidemiology, etiology)
• Dementia (blood, epidemiology, etiology)
• Female
• Follow-Up Studies
• Humans
• Incidence
• Male
• Proportional Hazards Models
• Risk Factors
• United States (epidemiology)
• Vitamin D (analogs & derivatives, blood)
• Vitamin D Deficiency (blood, complications, epidemiology)