Brain vitamin D related to cognitive function

An autopsy study showed that vitamin D levels in postmortem brain tissue were associated with cognitive function.

High concentration of 25(OH)D₃ — The primary form of vitamin D evaluated in this study — A 25% to 33% reduction in the likelihood of dementia or mild cognitive impairment in four areas of the brain, according to Sarah Booth, Ph.D., Tufts University, Boston Did. and colleagues.

However, brain levels of vitamin D were not associated with neuropathology or biomarker outcomes. Alzheimer’s disease and dementia.

Claire Sexton, DPhil, senior director of scientific programs and outreach at the Alzheimer’s Association in Chicago, said the relationship between vitamin D and cognitive function has been explored before, with mixed results. MedPage Today“Some studies found an association, some didn’t.”

Dr. Sexton said, “This study is an observational study, not an intervention, so while there is an intriguing possible association, we cannot prove that vitamin D levels cause a reduction in risk.” I need it to answer your question.”

“Finding an association between vitamin levels and reduced risk is not the same as endorsing supplementation,” Sexton noted. Trials have had mixed results and side effects, and starting vitamin D supplementation to reduce the risk of dementia is not recommended.”

The purpose of this study was to analyze brain levels of vitamin D and determine whether associations exist with cognitive measures and neuropathology outcomes.

“Although many studies, including many on vitamin D, have implicated dietary and nutritional factors in cognitive performance and function in older adults, they have all value-based,” said co-author M. Kyla Shea, also a PhD from Tufts University. “We wanted to know whether vitamin D is present in the brain and, if so, how their levels are associated with cognitive decline.

Researchers evaluated 25(OH)D₃ and other vitamin D forms are found in postmortem tissues of 290 deceased participants located in four regions of the brain: central frontal and temporal cortex, cerebellum, and anterior basin. Lash Memory and Aging ProjectDeaths whose brains were preserved for more than 6 years were excluded.

Global Alzheimer’s pathology included numbers of neuritic plaques, diffuse plaques, and neurofibrillary tangles. Gross and microscopic cerebral infarcts were identified, as were Lewy bodies.

The average age of death among participants was 92 years. Most were women (77%) and had at least 12 years of education (72%).

Cognitive assessments were performed annually. At the previous clinic visit, 40% of the participants had a diagnosis of dementia, 24% had mild cognitive impairment, and 36% had no cognitive impairment.

Each doubling of 25(OH)D was associated with a 25% to 33% lower chance of developing dementia or mild cognitive impairment at the previous visit.₃ 4 regions of the brain (OR 0.669-0.754, P.≤0.031 for all). Brain vitamin D concentrations were correlated across regions (within-class correlation coefficient 0.87) but were not associated with assessed neuropathological outcomes.

Plasma total 25(OH)D₃ and free 25(OH)D were moderately correlated with brain 25(OH)D₃ (r 0.32-0.39, P.≤0.0001), free 25(OH)D was not significantly associated with cognitive function.

Other forms of vitamin D were below detection limits in more than half of the brains analyzed, limiting our ability to assess 1,25(OH) relevance.₂D.₃ — the biologically active form of vitamin D — associated with cognition or pathology, the researchers acknowledged. Most of the fatalities were Caucasian, they added, and the results may not apply to others.

“We now know that vitamin D is present in reasonable amounts in the human brain and appears to be correlated with less cognitive decline.” , further research is needed to identify neuropathologies in which vitamin D is associated in the brain.”