May 1995

An In Vivo Study of the Prefrontal Cortex of Schizophrenic Patients at Different Stages of Illness via Phosphorus Magnetic Resonance Spectroscopy

Author Affiliations

From the Magnetic Resonance Spectroscopy Unit (Dr Stanley), Montreal (Quebec) Neurological Institute; Department of Nuclear Medicine and Magnetic Resonance, St Joseph's Health Centre (Drs Drost, Carr, and Thompson); and the Departments of Psychiatry (Drs Williamson and Malla) and Physiology (Dr Rylett), University of Western Ontario, London.

Arch Gen Psychiatry. 1995;52(5):399-406. doi:10.1001/archpsyc.1995.03950170073010

Background:  In this study, phospholipid metabolism of cell membranes, high-energy phosphate metabolism, and intracellular free magnesium concentration in the prefrontal cortex of first-episode drug-naive schizophrenic patients and medicated schizophrenic patients at different stages of illness were compared with those of controls.

Methods:  Localized in vivo phosphorus 31 magnetic resonance spectra of the left dorsolateral prefrontal cortex of 11 drug-naive, eight newly diagnosed medicated, and 10 chronic medicated patients with schizophrenia were compared with controls of similar gender, education, parental education, and handedness.

Results:  Significantly decreased levels of phosphomonoesters in drug-naive, newly diagnosed medicated, and chronic medicated patients and significantly increased levels of phosphodiesters in drug-naive patients were observed when compared with controls. There were no significant differences in the levels of high-energy phosphate metabolites between the groups except for a significant decrease in the inorganic orthophosphate levels of newly diagnosed medicated patients. A significant increase in the intracellular free magnesium concentration was observed in drug-naive, newly diagnosed medicated, and chronic medicated patients compared with controls. There were no correlations between the patients' negative and positive symptoms and the observed phosphorus-containing metabolites.

Conclusions:  A reduction in precursors of membrane phospholipid are observed during the early and chronic stages of the schizophrenia illness, and breakdown products of membrane phospholipids are increased at the early stage of illness before medication treatment.