title: Prediction of psychosis by mismatch negativity.
abstract: BACKGROUND
  To develop risk-adapted prevention of psychosis, an accurate estimation of the individual risk of psychosis at a given time is needed. Inclusion of biological parameters into multilevel prediction models is thought to improve predictive accuracy of models on the basis of clinical variables. To this aim, mismatch negativity (MMN) was investigated in a sample clinically at high risk, comparing individuals with and without subsequent conversion to psychosis.
  
  
  METHODS
  At baseline, an auditory oddball paradigm was used in 62 subjects meeting criteria of a late risk at-state who remained antipsychotic-naive throughout the study. Median follow-up period was 32 months (minimum of 24 months in nonconverters, n = 37). Repeated-measures analysis of covariance was employed to analyze the MMN recorded at frontocentral electrodes; additional comparisons with healthy controls (HC, n = 67) and first-episode schizophrenia patients (FES, n = 33) were performed. Predictive value was evaluated by a Cox regression model.
  
  
  RESULTS
  Compared with nonconverters, duration MMN in converters (n = 25) showed significantly reduced amplitudes across the six frontocentral electrodes; the same applied in comparison with HC, but not FES, whereas the duration MMN in in nonconverters was comparable to HC and larger than in FES. A prognostic score was calculated based on a Cox regression model and stratified into two risk classes, which showed significantly different survival curves.
  
  
  CONCLUSIONS
  Our findings demonstrate the duration MMN is significantly reduced in at-risk subjects converting to first-episode psychosis compared with nonconverters and may contribute not only to the prediction of conversion but also to a more individualized risk estimation and thus risk-adapted prevention.
authors.affiliation: Department of Psychiatry and Psychotherapy, University of Cologne, Germany. mitja.bodatsch@uk-koeln.de
authors.forename: Mitja
authors.initials: M
authors.lastname: Bodatsch
authors.forename: Stephan
authors.initials: S
authors.lastname: Ruhrmann
authors.forename: Michael
authors.initials: M
authors.lastname: Wagner
authors.forename: Ralf
authors.initials: R
authors.lastname: Müller
authors.forename: Frauke
authors.initials: F
authors.lastname: Schultze-Lutter
authors.forename: Ingo
authors.initials: I
authors.lastname: Frommann
authors.forename: Jürgen
authors.initials: J
authors.lastname: Brinkmeyer
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Gaebel
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Maier
authors.forename: Joachim
authors.initials: J
authors.lastname: Klosterkötter
authors.forename: Anke
authors.initials: A
authors.lastname: Brockhaus-Dumke
mesh_terms: D000161:Acoustic Stimulation / Q000379:methods; D000293:Adolescent; D000328:Adult; D001921:Brain / Q000503:physiopathology*; D003265:Contingent Negative Variation / Q000502:physiology*; D004569:Electroencephalography; D005260:Female; D007839:Functional Laterality; D006801:Humans; D008297:Male; D009483:Neuropsychological Tests; D011237:Predictive Value of Tests; D016016:Proportional Hazards Models; D011569:Psychiatric Status Rating Scales; D011571:Psychoacoustics; D011618:Psychotic Disorders / Q000175:diagnosis* / Q000473:pathology / Q000503:physiopathology*; D012307:Risk Factors; D055815:Young Adult