[Cognitive impairments associated with schizophrenic psychoses : Diagnostics, course and therapy].

Background: Longitudinal outcome studies confirm that the majority of patients with schizophrenic psychoses develop cognitive impairments associated with schizophrenia (CIAS).

Objective: To provide an overview of the epidemiology, diagnostics and evidence for various treatment options for CIAS.

Material and methods: Literature review of the current level of evidence regarding the efficacy of different treatment strategies for CIAS.

Results: Up to 85% of patients with schizophrenic psychoses exhibit CIAS, in some cases even before the development of positive or negative symptoms. The CIAS are associated with extensive individual burden due to impairments in many areas of cognitive and psychosocial functioning relevant to daily life. Various test instruments are available for clinical assessment with the Mental Health's Measurement and Treatment Research to Improve Cognition in Schizophrenia (MATRICS) consensus cognitive battery (MCCB) as an established standard for clinical trials and special clinical issues. The treatment of CIAS warrants a multimodal approach with non-drug strategies (e.g., cognitive remediation, exercise) currently providing the best level of evidence. Noninvasive neurostimulation procedures and dopaminergic antipsychotic drugs of the first and second generations have demonstrated low effectiveness on cognitive function disorders in schizophrenic psychoses.

Conclusion: The CIAS is a frequent disease-immanent symptom in schizophrenic psychoses that should be considered in the clinical routine as it substantially impairs those affected in the functional level and quality of life. Current treatment options are limited but innovative psychosocial interventions show low to moderate effects. In addition, new medications developed based on current neurobiological findings and combinations with psychosocial and neurostimulation procedures could open up new perspectives.