Alteration of regional cerebral glucose utilization with delusions in Alzheimer's disease.

The authors examined 65 patients with Alzheimer's disease for delusions and explored the relationship of delusions with regional cerebral glucose metabolism determined by [18F]fluorodeoxyglucose PET. In patients with delusions (n = 26), normalized glucose metabolism was significantly increased in the left inferior temporal gyrus and significantly decreased in the left medial occipital region as compared with those without delusions (n = 39). The two groups were similar in age, sex, and dementia severity. These results suggest that delusions in Alzheimer's disease are attributable to a dysfunction in specific brain areas rather than a simple reaction to intellectual deficits.