[Evaluation of correlations between cognitive performances and clinical dimensions of schizophrenia]

Abstract

Background: Schizophrenia is characterised by positive and negative symptoms as well as thought disorders and disorganised behaviour. Multiple cognitive deficits within the areas of memory, attention and executive functions are also associated with schizophrenia. Aim of the study was to proceed to a study of correlations between clinical dimensions of schizophrenia and cognitive functions.

Methods: The authors recruited 105 patients suffering from schizophrenia spectrum disorders (DSM IV criteria). The patients were clinically stabilised, showing no depressive state at the time of the study, with no organic brain disorders and no history of drug intake. They were clinically evaluated using the PANSS and the Calgary Depression Scale. A cognitive battery was also administered.

Results: Positive dimension of schizophrenia was shown to be independent from any cognitive function. Disorganisation was negatively correlated to attention, working memory, long-term verbal memory and executive functions. Negative dimension was negatively correlated with working memory and executive functions.

Conclusion: Cognition wasn't correlated to the positive dimension of schizophrenia whereas it was correlated to the negative and to the disorganisation dimension of the disease. This is probably due to overlapping of concepts.