Regional cerebral blood flow in late-life-onset psychos

Eighteen patients with an onset of psychosis after the age of 45 [laterlife psychosis (LLP)] and 12 with late-life onset psychotic depression (LLPD) were studied and compared to 30 elderly controls utilizing magnetic resonance imaging (MR1) and brain single photon emission computerized tomography (SPECT) with 99mTc hexamethyl propyleneamine oxime. In the LLP group 55% had a clinical and MRI evaluation suggesting cerebrovascular disease, compared to 33% in the LLPD and 7% in the elderly controls. Six percent of the LLP, 33% of the LLPD, and 3% of the controls had clinical evidence of early degenerative dementia. In most cases, SPECT confirmed clinical and MRI findings. Thirteen of 18 LLP, 8 of 12 LLPD and only 4 of 30 controls had abnormal SPECT. Eighty-three percent of the LLP and 83% of the LLPD groups had at least one small area of hypoperfusion in either the temporal or frontal regions, compared to 27% of the controls. This work suggests a possible role for the use of SPECT in the study of patients with late-life psychosis and late-life depression.