Neurology. 2010 Jan 5;74(1):18-26. Epub 2009 Nov 25.

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

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 (< or =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 (< or =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.

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Am J Geriatr Psychiatry. 2006 Dec;14(12):1032-40.

Vitamin D deficiency is associated with low mood and worse cognitive performance in older adults.

BACKGROUND: Vitamin D deficiency is common in older adults and has been implicated in psychiatric and neurologic disorders. This study examined the relationship among vitamin D status, cognitive performance, mood, and physical performance in older adults. METHODS: A cross-sectional group of 80 participants, 40 with mild Alzheimer disease (AD) and 40 nondemented persons, were selected from a longitudinal study of memory and aging. Cognitive function was assessed using the Short Blessed Test (SBT), Mini-Mental State Exam (MMSE), Clinical Dementia Rating (CDR; a higher Sum of Boxes score indicates greater dementia severity), and a factor score from a neuropsychometric battery; mood was assessed using clinician's diagnosis and the depression symptoms inventory. The Physical Performance Test (PPT) was used to measure functional status. Serum 25-hydroxyvitamin D levels were measured for all participants. RESULTS: The mean vitamin D level in the total sample was 18.58 ng/mL (standard deviation: 7.59); 58% of the participants had abnormally low vitamin D levels defined as less than 20 ng/mL. After adjusting for age, race, gender, and season of vitamin D determination, vitamin D deficiency was associated with presence of an active mood disorder (odds ratio: 11.69, 95% confidence interval: 2.04-66.86; Wald chi(2) = 7.66, df = 2, p = 0.022). Using the same covariates in a linear regression model, vitamin D deficiency was associated with worse performance on the SBT (F = 5.22, df = [2, 77], p = 0.044) and higher CDR Sum of Box scores (F = 3.20, df = [2, 77], p = 0.047) in the vitamin D-deficient group. There was no difference in performance on the MMSE, PPT, or factor scores between the vitamin D groups. CONCLUSIONS: In a cross-section of older adults, vitamin D deficiency was associated with low mood and with impairment on two of four measures of cognitive performance.

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J Natl Med Assoc. 2009 Apr;101(4):349-54.


BACKGROUND: Vitamin D deficiency is common in older adults and is more prevalent among persons with darker pigmented skin. The detrimental effects of vitamin D deficiency on the bone are widely known; however, recent data suggest that vitamin D deficiency may contribute to other disorders, including low mood, cognitive impairment, and impaired mobility. OBJECTIVE: The purpose of this study was to determine whether nonskeletal diseases such as depression, cognitive impairment, and physical disability, which have been associated with vitamin D deficiency, are more commonly seen in older African Americans. DESIGN: In a cross-sectional study of 60 older adults (30 African Americans and 30 European Americans), vitamin D status, cognitive performance, physical performance, and bone mineral density (BMD) were assessed. Differences between groups and differences between those with vitamin D deficiency and those with normal vitamin D levels were tested. RESULTS: African Americans had a lower mean 25-hydroxyvitamin D level (17.98 ng/ml; SD, 6.9) compared to European Americans (25.20 ng/ml; SD, 7.0; p < .0001). Participants with vitamin D deficiency performed worse on a measure of cognitive performance, the Short Blessed Test (10.87 vs 6.31; p = .016); the Physical Performance Test (PPT) (27.00 vs 28.96; p = .039); and had lower BMD (0.823 vs 0.914; p = .005) and t scores (-1.29 vs -0.72; p = .008) of the hip. Among African Americans, vitamin D deficiency was associated with worse cognitive performance and lower BMD of the hip. CONCLUSIONS: Vitamin D deficiency in older African Americans was associated with worse cognitive performance and lower BMD of the hip.