A systematic review of diffusion tensor imaging studies in obesity

Area of Science:

• Neuroscience
• Radiology
• Public Health

Background:

• Obesity is a global health crisis with severe complications.
• Obesity is consistently linked to structural brain changes.
• Diffusion tensor imaging (DTI) assesses white matter integrity via water diffusion dynamics.

Purpose of the Study:

• To systematically review microstructural white matter alterations in obesity using DTI.
• To synthesize findings from cross-sectional studies comparing individuals with obesity and lean controls.

Main Methods:

• Computerized literature search of PubMed, Web of Science, and Livivo databases.
• Inclusion/exclusion criteria applied to 31 cross-sectional studies.
• Analysis of fractional anisotropy (FA) and mean diffusivity (MD) in white matter tracts.

Main Results:

• Most studies reported decreased FA and increased MD in individuals with obesity, indicating white matter abnormalities.
• Observed alterations in white matter microstructure were inconsistent across studies.
• Potential biases and methodological variations may explain inconsistencies.

Conclusions:

• Obesity is associated with white matter abnormalities, but the pattern is not uniform.
• Further research incorporating direct body fat assessment is recommended for a clearer brain-body relationship.
• Standardized methodologies and quality assessments are crucial for future DTI studies in obesity.