25-Hydroxyvitamin D, dementia, and cerebrovascular pathology in elders receiving home services

J. S. Buell PhD, B. Dawson-Hughes MD, T. M. Scott PhD, D. E. Weiner MD, MS, G. E. Dallal PhD, W. Q. Qui MD, PhD, P. Bergethon MD, I. H. Rosenberg MD, M. F. Folstein MD, S. Patz PhD, R. A. Bhadelia MD, and K. L. Tucker PhD^* From the Friedman School of Nutrition Science and Policy (J.S.B., T.M.S., G.E.D., I.H.R., K.L.T.), Tufts University; Tufts Medical Center (T.M.S., D.E.W., W.Q.Q., M.F.F., S.P., R.A.B.), Tufts University School of Medicine; Jean Mayer USDA Human Nutrition Research Center on Aging (B.D.-H., G.E.D., I.H.R., K.L.T.); Beth Israel Deaconess Medical Center (R.A.B.); and Boston University Medical Center (P.B.), Boston, MA.

Background: Vitamin D deficiency has potential adverse effects on neurocognitive health and subcortical function. However, no studies have examined the association between vitamin D status, dementia, and cranial MRI indicators of cerebrovascular disease (CVD).

Methods: Cross-sectional investigation of 25-hydroxyvitamin D [25(OH)D], dementia, and MRI measures of CVD in elders receiving home care (aged 65–99 years) from 2003 to 2007.

Results: Among 318 participants, the mean age was 73.5 ± 8.1 years, 231 (72.6%) were women, and 109 (34.3%) were black. 25(OH)D concentrations were deficient (<10 ng/mL) in 14.5% and insufficient (10–20 ng/mL) in 44.3% of participants. There were 76 participants (23.9%) with dementia, 41 of which were classified as probable AD. Mean 25(OH)D concentrations were lower in subjects with dementia (16.8 vs 20.0 ng/mL, p < 0.01). There was a higher prevalence of dementia among participants with 25(OH)D insufficiency (20 ng/mL) (30.5% vs 14.5%, p < 0.01). 25(OH)D deficiency was associated with increased white matter hyperintensity volume (4.9 vs 2.9 mL, p < 0.01), grade (3.0 vs 2.2, p = 0.04), and prevalence of large vessel infarcts (10.1% vs 6.9%, p < 0.01). After adjustment for age, race, sex, body mass index, and education, 25(OH)D insufficiency (20 ng/mL) was associated with more than twice the odds of all-cause dementia (odds ratio [OR] = 2.3, 95% confidence interval [CI] 1.2–4.2), Alzheimer disease (OR = 2.5, 95% CI 1.1–6.1), and stroke (with and without dementia symptoms) (OR = 2.0, 95% CI 1.0–4.0).

Conclusions: Vitamin D insufficiency and deficiency was associated with all-cause dementia, Alzheimer disease, stroke (with and without dementia symptoms), and MRI indicators of cerebrovascular disease. These findings suggest a potential vasculoprotective role of vitamin D.