Transition to psychosis: Neuropsychological test results of the epos study

Abstract

Introduction:Both schizophrenia and ultra high risk (UHR) patients show reduced neurocognitive performance compared to matched healthy control subjects. In the current study we compared neurocognitive performance at baseline and follow up between UHR patients who made the transition to psychosis and patients who did not.Method:Patients were eligible for the study when they met criteria for one or more of the following groups: Attenuated symptoms or brief limited intermitted psychotic symptoms or a first degree family member with a psychotic disorder and reduced functioning or basic symptoms. We assessed 216 UHR patients (166 males, mean age: 22,6 SD 5,2) with a neuropsychological test battery composed of the National adult reading test (premorbid IQ), California verbal memory test (verbal memory), spatial working memory test, verbal fluency first letter and categories (executive functioning), finger tapping test (motor speed) and continuous performance test (sustained attention). Data were collected in 7 participating centres of EPOS. Follow up was at 9 months.Results:37 UHR patients made the transition to psychosis (25 males, mean age 21,5 SD 4,8). The only test that showed a significant difference between the transition and non transition group at baseline was verbal fluency categories (t= 2.79, p = 0.006).Conclusion:Patients who later make the transition to psychosis perform significantly worse on verbal fluency categories than patients who do not make the transition to psychosis. Verbal fluency may contribute to an improved prediction of psychosis in UHR patients. Follow up results will also be presented.