Vitamin D and brain volumetric changes: Systematic review and meta-analysis

Area of Science:

• Neuroscience
• Radiology
• Endocrinology

Background:

• Vitamin D plays a crucial role in nervous system function.
• Evidence suggests a link between vitamin D levels and brain health.
• Morphological brain changes associated with vitamin D status require systematic investigation.

Purpose of the Study:

• To systematically review and synthesize evidence on brain morphometric changes related to vitamin D depletion or repletion.
• To quantitatively analyze the location and nature of these changes.

Main Methods:

• A comprehensive Medline search was performed using relevant keywords for vitamin D and brain imaging techniques.
• Included observational studies (animal and human) were selected based on predefined criteria.
• A fixed-effects meta-analysis was conducted on eligible studies to assess lateral ventricle volume differences.

Main Results:

• Vitamin D depletion was associated with decreased brain volume, characterized by significantly larger lateral ventricles.
• The pooled effect size indicated a large effect of vitamin D depletion on ventricle enlargement.
• Brain atrophy patterns suggested loss of matter at the cranial vertex, potentially involving the precuneus cortex, rather than solely temporal lobe atrophy.

Conclusions:

• While vitamin D's action in the brain is increasingly recognized, data on associated morphological changes remain limited.
• A clear association between vitamin D depletion and brain atrophy, particularly enlarged ventricles, was identified.
• This finding provides a scientific rationale for conducting vitamin D replacement trials to investigate potential therapeutic benefits.