Essential fatty acids, lipid membrane abnormalities, and the diagnosis andtreatment of schizophrenia

Recent research suggests that deficient uptake or excessive breakdown of me mbrane phospholipids may be associated with schizophrenia. We review availa ble clinical research on abnormalities inn membrane fatty acid composition and metabolism in schizophrenia, and therapeutic trials of fatty acid in th is disorder. All potentially, relevant English-language articles were identified from th e medical and psychiatric literature with the aid of computer searches risi ng key words such as lipids, phospholipids, prostaglandins and schizophreni a. All studies which include human subjects are reviewed. Empirical studies related to membrane hypotheses of schizophrenia focus on: 1) assessment of prostaglandins (PGI and their essential fatty acid (EFA) precursors in the tissues of patients with schizophrenia; 2) evaluation of the niacin flush test as a possible diagnostic marker; 3) evaluation of pho spholipase enzyme activity; 4) NMR spectroscopy studies of brain phospholip id metabolism, and 5) therapeutic trials of PG precursors for the treatment of schizophrenia. The most consistent clinical findings include red blood cell fatty acid membrane abnormalities, NMR spectroscopy evidence of increa sed phospholipid turnover and a therapeutic effect of omega-3 fatty acid su pplementation of neuroleptic treatment in some schizophrenia patients, Studies of EFA metabolism have proved fruitful for generating and testing n ovel etiologic hypotheses and new therapeutic agents for schizophrenia. Gre ater attention to factors that influence tissue EFA levels such as diet, to bacco and alcohol al-e required to reconcile inconsistent findings. Treatme nt studies, although promising, require independent replication. (C) 1999 S ociety of Biological Psychiatry.