Cerebral 18F‐fluorodeoxyglucose metabolism alteration of reward‐ and motivation‐related regions in groups of different BMI classifications

Objective This study explored the relationship between BMI and regional cerebral glucose metabolism and explicitly detected regions with significant differences in cerebral metabolism using positron emission tomography (PET)/magnetic resonance imaging in the resting state. Methods Corresponding PET images acquired from 220 participants were sorted into four groups according to Asian BMI standards: underweight, normal weight, overweight, and obesity. Pearson correlation coefficient analysis was performed to assess the association between BMI and standard uptake value. The regional cerebral glucose metabolism was measured in the fasted state. The PET images were analyzed using statistical parameter maps. One‐way ANOVA was used to explore differences in the standard uptake value as an indicator of regional cerebral glucose metabolism. Results This study found that lower cerebral glucose metabolism in reward‐ and motivation‐related regions was accompanied by more severe obesity and that regional cerebral glucose metabolism activities were negatively correlated with BMI. In addition, more severe obesity was accompanied by a larger range of areas with significant differences independent of current dietary status. Conclusions These findings suggest that the reward and motivation circuits may be a factor regulating energy balance and influencing the degree of obesity.