Right prefrontal hypometabolism predicts delusions in dementia with Lewy bodies.

Delusions (DEL) are frequent in dementia with Lewy bodies (DLB); however, the neural equivalent is poorly understood. The present study therefore aimed to identify the cerebral metabolic pattern of glucose of a DLB group suffering from DEL (DLB+DEL) as compared to a non-delusional group (DLB-DEL) and a control group (NL); and to determine the predictive value of the regional metabolic deficit for DEL symptomatology in comparison to other clinical variables significantly associated with DEL. Voxel-wise comparisons were conducted between the patient and control groups in SPM2. The most significant regional metabolic deficit of the DLB+DEL group was used a predictor for DEL symptomatology in a logistic regression analysis along with other variables significantly associated with DEL, such as visual hallucinations (VH), and overall cognitive impairment. A significant relative hypometabolism of the right prefrontal cortex was found in the DLB+DEL group, which predicted DEL symptomatology in the regression analysis. VH and overall cognitive dysfunction were no significant predictors. These results underline the significance of right prefrontal damage for DEL in DLB.