Neurocognitive functioning in patients with first-episode schizophrenia : results of a prospective 5-year follow-up study

Abstract

To assess the course of neuropsychological (NP) impairment in schizophrenia, 71 patients with first episode (FE) schizophrenia and 71 healthy controls were given a comprehensive battery of NP tests at index assessment, after a 2-year and after a 5-year follow-up period. By means of the z-score standardization, summary scores for verbal intelligence (VBI), spatial organisation (SPT), verbal fluency (VBF), Verbal learning (VBL), semantic memory (SEM), visual memory (VIM), delay/retention rate (DEL), short-term memory (STM), visuomotor processing and attention (VSM) and abstraction/flexibility (ABS) were constructed. FE schizophrenia patients showed a worse performance compared to controls in all areas investigated, most pronounced in VSM, SEM and VBL. In the majority of cognitive domains, an improvement was found over the 5-year follow-up period without differences between the two groups. However, in VBF patients slightly deteriorated whilst controls improved and in memory functions patients improved less compared to controls. When controlling for relevant confounders, neither conventional nor atypical neuroleptics showed a deleterious influence on NP performance, except on VBF. Our data suggest that NP impairment is already present at the onset of the illness and remains stable over the early course of schizophrenia.