The effects of aging on changes in regional cerebral blood flow in schizophrenia.

AIMS Although there have been no conclusive pathophysiological findings in support of the degeneration theory in the etiology of schizophrenia to date, results of our neuroimaging studies suggest functional changes in the brains of schizophrenics. We evaluated age-related changes of brain perfusion in medicated patients with schizophrenia. METHOD In this study, we evaluated age-related changes in brain perfusion in medicated schizophrenia patients (n = 44) and control subjects (n = 37) undergoing (99m)Tc-ethyl cysteinate dimer single-photon emission computed tomography. RESULT Although the regional cerebral blood flow (rCBF) was found to be reduced in bilateral frontal lobes by analysis with age in the patients with schizophrenia, significant differences compared to controls in age effects on perfusion were found in the patients with schizophrenia in bilateral temporal lobes. Moreover, in multiple regression analysis including age, total time of treatment and overall neuroleptic dose, rCBF was found to be reduced in bilateral frontal and parietal lobes. As a result, cerebral perfusion in temporal lobes with schizophrenia might be related to age rather than medication. CONCLUSION In this study, the patients with schizophrenia appeared to have significant bilateral temporal hypoperfusion related to age compared with controls. And bilateral temporal rCBF is decreased in patients with schizophrenia and even more in older schizophrenia patients. These changes might be consistent with degenerative changes observed in patients with schizophrenia and be a promising method for the efficient development of a treatment strategy by measuring temporal perfusion in patients with schizophrenia.