PREDICTION OF FIRST-EPISODE PSYCHOSIS: BASIC SYMPTOM AND ULTRA HIGH RISK (UHR) CRITERIA F. Schultze-Lutter 1 , S. Ruhrmann 1 , H. Picker 1 , J. Klosterkötter 1 . 1 Department of Psychiatry and Psychotherapy University of Cologne, Cologne, Germany Presenting Author details: frauke.schultze-lutter@uk-koeln.de FETZ, 50924 Cologne, Germany, Tel.: +49 221 4786098; fax: +49 221 4783738. Background: Basic symptoms were suggested as a complement to the ‘ultra high risk’ approach to an early detection of psychosis. Along with attenuated symptoms, they were studied prospectively for their predictive ability and socio-demographic factors potentially influen- cing conversion. Methods: One hundred and forty-six subjects putatively prodromal by cognitive–perceptive symptoms were assessed with the Schizophrenia Proneness Instrument, Adult version (SPI-A), Structured Interview for Prodromal Syndromes (SIPS) and Positive and Negative Syndrome Scale (PANSS). They were followed up for a conversion to psychosis over a mean period of 20.6 ± 16.0 months. Results: Comparing baseline data of the 56 with and the 90 without a development of psychosis, significant differences showed for the SPI- A ‘Cognitive Disturbances’, SIPS ‘Positive Symptoms’, ‘Negative Symptoms’ and ‘Disorganization Symptoms’ and PANSS ‘Negative Scale’. The relevance of subtle cognitive disturbances, mild negative and attenuated disorganized symptoms to conversion was supported by stepwise logistic regression analyses, which, at about 76% of cases correctly classified, included SIPS ‘Disorganized Symptoms’, PANSS ‘Negative Scale’ and SPI-A ‘Cognitive Disturbances’ and ‘Cognitive– Attentional Impediments’ as well as highest school graduation. Conclusions: The results underline the importance of more peculiar self-experienced cognitive disturbances in the early detection of psychoses. Yet, already at baseline, prodromal patients who have meanwhile converted to psychosis (true-positives) showed more/more severe symptoms in most areas. Attenuated disorganized symptoms might facilitate prediction of conversion and supplement APS in the early detection of the disorganized subtype. The severity of ‘non- specific’ symptoms – especially negative symptoms – should be considered in the estimation of the ‘real’ risk of psychosis in those symptomatically considered to be at an increased risk. Acknowledgement: The study was supported by a grant of the German Research Foundation (DFG) to Prof. Klosterkötter, Dr. Schultze-Lutter and Prof. Steinmeyer. doi:10.1016/j.schres.2007.12.016 NEGATIVE FEATURES OF PSYCHOSIS PRECEDE ONSET OF PSYCHOSIS IN A PROSPECTIVE GENERAL POPULATION SAMPLE OF ADOLESCENTS P.H. Mäki 1,2 , J. Miettunen 1 , M. Kaakinen 3 , A. Taanila 3 , P.B. Jones 4 , G. Murray 4 , I. Moilanen 5 , M. Joukamaa 6 , M. Heinimaa 7 , J.M. Veijola 8 . 1 Department of Psychiatry, University of Oulu, Finland 2 University Hospital of Oulu, Finland 3 Department of Public Health Science and General Practice, University of Oulu, Finland 4 Department of Psychiatry, University of Cambridge, UK 5 Clinic of Child Psychiatry, University of Oulu, Finland 6 Tampere School of Public Health, University of Tampere and Department of Psychiatry, Tampere University Hospital, Tampere, Finland 7 University of Turku, Finland 8 The Academy of Finland, Finland Presenting Author details: pirjo.maki@oulu.fi P.O. Box 5000, 90014 Oulu, Finland, Tel.: +358 8 3156815; fax: +358 8 333167. Background: To our knowledge, there does not exist any prospective study in general population of adolescents exploring symptoms predicting the onset of first episode psychosis. Methods: Members (N = 9215) of the Northern Finland 1986 Birth Cohort, an unselected general population cohort (Järvelin et al. 1993), were invited to participate in a field survey during 2001, at ages of 15– 16 years. The study included a 21-item PROD-screen questionnaire screening prodromal symptoms for psychosis for last 6 months (Heinimaa et al., 2003). PROD-screen included nine questions for positive and five questions for negative symptoms. The Finnish Hospital Discharge Register was used to find out new cases of hospital treated mental disorders during 2002–2005. Results: Of the subjects, 17 (0.3%) were treated due to first episode psychosis and 95 (1.5%) due to non-psychotic disorder during the follow-up period. Positive symptoms did not associate with the onset of psychosis, but negative symptoms did. 94% of subjects who got psychosis reported negative symptoms. Respective figure for those who were treated for non-psychotic disorder was 48%, and for those ‘healthy’ without psychiatric hospital treatment 46% (Fisher's exact test: psychosis vs. healthy p b 0.001, psychosis vs. non-psychosis p b 0.001, and non-psychosis vs. healthy p = 0.61). Conclusions: This study may be the only one exploring prospectively in general population symptoms predicting onset of first episode psychosis. The findings emphasize the importance of negative symptoms in the development of first episode psychosis (Weinberger, 1995). Acknowledgement: The Academy of Finland, the National Institute of Mental Health, the Signe and Ane Gyllenberg Foundation, the Sigrid Juselius Foundation and the Thule Institute, Finland. References: Heinimaa M et al. Int J Methods Psychiatric Res 2003; 12(2): 92–104. Järvelin M-R et al. Br J Obstet Gynaecol 1993; 100: 310–315. Weinberger DR. Lancet 1995; 346: 552–57. doi:10.1016/j.schres.2007.12.017 DURATION OF UNTREATED PSYCHOSIS AND CHANGES OF BRAIN STRUCTURE IN SCHIZOPHRENIA WITHIN THE NORTHERN FINLAND 1966 BIRTH COHORT M.S. Penttila 1 , E. Lauronen 1 , H.J. Koponen 1,2 , J. Miettunen 1 , M.K. Isohanni 1 . 1 Department of Psychiatry, University of Oulu and Oulu University Hospital, Finland 2 Department of Psychiatry, University of Kuopio, Finland 10 ABSTRACTS / Schizophrenia Research 98 (2008) 3–199