Correlation of cortical gray/white matter ratio and body mass index (BMI) in controls and major depression patients scanned with 7T MRI

Motivation: Better understand the relationship between depression, obesity and the brain. Goal(s): Investigate the relationship between body mass index and brain gray and white matter volumes using high-resolution 7T MRI in a population of healthy controls and major depression patients. Approach: T1-weighted MRI was obtained at 7T and segmented using FreeSurfer. 44 MDD patients and 47 healthy controls of comparable age and body mass index (BMI) were scanned. Results: BMI showed significant positive correlation with white matter volume and negative correlation between gray matter volume and gray/white ratios in healthy controls and combined cohorts. Similar, though non-significant trends were observed in MDD patients. Impact: The presented study is the first to ultrahigh field MRI to detect significant correlations between BMI and gray/white matter brain volumes. Differences in these correlations were observed between MDD patients and healthy controls.