Three very recent publications have detailed that biomarkers can identify and quantify high-risk or prodromally symptomatic subjects who subsequently undergo conversion to psychosis. McGuire and his group (Howes et al., 2011) used fluoro-dopa positron emission tomography scanning to measure dopamine synthesis. Koutsouleris et al. (Koutsouleris et al., 2011) used structural MRI data to develop a neuroanatomical classification system for predicting psychosis conversion, and Amminger et al. (Amminger et al., 2011) used capillary gas chromatography of erythrocyte membrane fatty acid levels to provide information about brain phospholipids. All measures were significantly successful in identifying high-risk or prodromally symptomatic subjects who went on to develop a first episode of psychosis.

These papers point to an exciting future in our efforts to elaborate easily identifiable risk factors that can pinpoint among clinically identified "prodromal" subjects those who are most likely to become psychotic. That such diverse measures proved to be successful in identifying "true positives" can be regarded as a milestone in this line of investigation. It represents a quantitative leap forward in our ability to reduce the uncertainty of predicting psychosis, and hints at the day when tragedies such as the one occurring in Tucson, Arizona, become a thing of the past.

References:

Howes OD, Bose SK, Turkheimer F, Valli I, Egerton A, Valmaggia LR, Murray RM, McGuire P. Dopamine Synthesis Capacity Before Onset of Psychosis: A Prospective [18F]-DOPA PET Imaging Study. Am J Psychiatry. 2011 Dec 1; 168: 1311-1317. Abstract

Koutsouleris N, Borgwardt S, Meisenzahl EM, Bottlender R, Möller HJ, Riecher-Rössler A. Disease Prediction in the At-Risk Mental State for Psychosis Using Neuroanatomical Biomarkers: Results From the FePsy Study. Schizophr Bull. 2011 Nov 10. Abstract

Amminger GP, Schäfer MR, Klier CM, Slavik JM, Holzer I, Holub M, Goldstone S, Whitford TJ, McGorry PD, Berk M. Decreased nervonic acid levels in erythrocyte membranes predict psychosis in help-seeking ultra-high-risk individuals. Mol Psychiatry. 2011 Dec 20. Abstract

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