The interaction between depression diagnosis and BMI is related to altered activation pattern in the right inferior frontal gyrus and anterior cingulate cortex during food anticipation

Background Depression and overweight/obesity often cooccur but the underlying neural mechanisms for this bidirectional link are not well understood. Methods In this functional magnetic resonance imaging study, we scanned 54 individuals diagnosed with depressive disorders (DD) and 48 healthy controls (HC) to examine how diagnostic status moderates the relationship between body mass index (BMI) and brain activation during anticipation and pleasantness rating of food versus nonfood stimuli. Results We found a significant BMI-by-diagnosis interaction effect on activation in the right inferior frontal gyrus (RIFG) and anterior cingulate cortex (ACC) during food versus nonfood anticipation (p < .0125). Brain activation in these regions was greater in HC with higher BMI than in HC with lower BMI. Individuals with DD showed an opposite pattern of activation. Structural equation modeling revealed that the relationship between BMI, activation in the RIFG and ACC, and participants' desire to eat food items shown in the experiment depended on the diagnostic status. Conclusions Considering that food anticipation is an important component of appetitive behavior and that the RIFG and ACC are involved in emotion regulation, response inhibition and conflict monitoring necessary to control this behavior, we propose that future clinical trials targeting weight loss in DD should investigate whether adequate mental preparation positively affects subsequent food consumption behaviors in these individuals.

Automated summary

Depression and overweight/obesity are often cooccurring, and this study found that the relationship between body mass index (BMI) and brain activation is moderated by diagnostic status. The activation in the right inferior frontal gyrus and anterior cingulate cortex was associated with food anticipation and pleasantness rating, which are important components of appetitive behavior. These findings suggest that future clinical trials targeting weight loss in individuals with depressive disorders should consider the role of mental preparation in affecting food consumption behaviors.