Vitamin D and white matter abnormalities in older adults: a cross‐sectional neuroimaging study

Abstract

Background and purpose: Morphological brain changes related to hypovitaminosis D have been poorly studied. In particular, the age-related decrease in vitamin D concentrations may explain the onset of white matter abnormalities (WMA) in older adults. Our objectives were (i) to investigate whether there was an association between serum 25-hydroxyvitamin D (25OHD) concentration and the grade of WMA in older adults and (ii) to determine whether the location of WMA was associated with 25OHD concentration. Methods: One hundred and thirty-three Caucasian older community-dwellers with no clinical hydrocephalus (mean 71.6 AE 5.6 years; 43.6% female) received a blood test and a magnetic resonance imaging scan of the brain. The grades of total, periventricular and deep WMA were scored using semiquantitative visual rating scales from T2-weighted fluid-attenuated inversion recovery images. The association of WMA with as-measured and deseasonalized 25OHD concentrations was evaluated with the following covariates: age, gender, body mass index, use of anti-vascular drugs, number of comorbidities, impaired mobility, education level, Mini-Mental State Examination score, medial temporal lobe atrophy, serum concentrations of calcium, thyroid-stimulating hormone and vitamin B12, and estimated glomerular filtration rate. Results: Both as-measured and deseasonalized serum 25OHD concentrations were found to be inversely associated with the grade of total WMA (adjusted b = À0.32, P = 0.027), specifically with periventricular WMA (adjusted b = À0.15, P = 0.009) but not with deep WMA (adjusted b = À0.12, P = 0.090). Similarly, participants with 25OHD concentration <75 nM had on average a 33% higher grade of periventricular WMA than those with 25OHD ≥75 nM (P = 0.024). No difference in average grade was found for deep WMA (P = 0.949). Conclusions: Lower serum 25OHD concentration was associated with higher grade of WMA, particularly periventricular WMA. These findings provide a scientific basis for vitamin D replacement trials.

Vitamin D Status and Rates of Cognitive Decline in a Multiethnic Cohort of Older Adults

“…Although the biological mechanisms associating dementia risk with low VitD levels are not fully understood, low VitD status has been associated with increased white matter hyperintensities 46,47 and enlarged ventricular volumes. 48 Serum 25-OHD is also associated with reduced β-amyloid 1-42 concentrations in cerebrospinal fluid, 47 a recognized risk factor for incident dementia.…”

Vitamin D in dementia prevention

“…Regarding brain vascular changes, experiments in rats showed that vitamin D attenuates cortical ischemia after cerebral arterial ligation . In humans, a meta‐analysis reported that those with hypovitaminosis D have more strokes than other groups, and a similar association was recently highlighted with cerebral small vessel disease . Among older adults, hypovitaminosis D was associated with an increased volume of white matter damage (WMD), specifically periventricular WMD, but not deep WMD …”

Cerebrovascular Correlates of Vitamin D Deficiency in Older Adults Living near the Equator: Results from the Atahualpa Project

“…Besides its well‐known consequences, such as interference with bone metabolism and increased predisposition to certain cancers, several studies have investigated a possible correlation between vitamin D deficiency and cerebrovascular disease. However, results have been inconsistent, with some studies showing a relationship between both conditions while others were showing no association . It is also possible the occurrence of a reverse causation phenomenon, by which persons with a stroke are more prone to develop vitamin D deficiency as they are less likely to be exposed to direct sunlight.…”