doi:10.1038/nindia.2015.155 Published online 24 November 2015
Using resting-state functional magnetic resonance imaging and blood tests, researchers have identified a link between vitamin B12 deficiency and cognitive decline1. They also found that vitamin B12 supplementation alleviated cognitive decline in patients by elevating serum levels of vitamin B12. Thus, such vitamin-replacement therapy may assist patients with cognitive impairment.
To devise a better technique to diagnose vitamin B12 deficiency and its link to brain damage, the researchers imaged different brain regions and measured the serum levels of vitamin B12 in 13 patients with cognitive impairment and in healthy individuals. Six of the patients received vitamin B12 supplementation.
Imaging data revealed that the patients with vitamin B12 deficiency showed lower regional homogeneity in the left and right hemispheres and hippocampus, the seat of memory in the brain, than healthy individuals.
The vitamin-deficient patients who received vitamin B12 supplementation showed increased regional homogeneity in the various brain regions. Brain regions that showed significant improvement after vitamin replacement therapy included the prefrontal cortex and hippocampus.
This study provides clinicians with a method for measuring functional alterations in the brain due to vitamin B12 deficiency as well as a way to reverse it, the researchers say,
1. Gupta, L. et al. Assessment of brain cognitive functions in patients with vitamin B12 deficiency using resting state functional MRI: a longitudinal study. Magn. Reson. Imaging (2015) doi: 10.1016/j.mri.2015.10.026