Die Bedeutung der Negativsymptomatik für kognitive Defizite bei Patienten mit Erstmanifestation einer Schizophrenie

Abstract

Patients with a first episode of schizophrenia may suffer from psychotic and disorganised symptoms, such as delusions, hallucination, bizarre behaviour and formal thought disorder, and from negative symptoms including flattening of affect, alogia, apathy/avolition, anhedonia and deficits in attention. There is solid evidence that neuropsychological abnormalities are also present at this stage of the illness, comprising deficits in domains of attention, executive function, verbal and non-verbal memory, spatial abilities, psychomotor functions, etc. We have recently shown that early, treatment-induced improvement of negative symptoms is significantly associated with cognitive performance during a follow-up period of two years. In this study the impact of early, treatment-induced change of negative symptoms on cognitive performance during a follow-up of 2 years was examined in a larger sample of neuroleptic-naive patients with first-episode schizophrenia. Forty-three patients with a diagnosis of schizophrenia or schizoaffective disorder according to DSM-IV underwent a comprehensive clinical and neuropsychological test battery at the time of study inclusion and after approximately 5 weeks, 6, 12 and 24 months of follow-up. A healthy comparison group with similar age, gender distribution and parental socio-economic status was also included. Patients showed marked cognitive deficits at baseline and throughout the follow-up. Early, treatment-induced improvement of negative symptoms predicted better cognitive performance at follow-up. Early, treatment-induced improvement of cognitive performance was significantly associated with less negative and psychotic symptoms. The results of this study suggest a clinical relevant association between early change in negative symptoms and cognitive outcome, and between early improvement of cognitive performance and symptomatic outcome. Negative symptoms and cognitive deficits should be considered as primary treatment targets in the early course of schizophrenia.