Insight, symptoms and executive functions in schizophrenia

Abstract

Introduction: We investigated the relationship of insight with executive functions and symptoms in a group of stabilised inpatients with schizophrenia.

Methods: Executive functions using an extensive battery constituted of several tests as well as psychopathology were assessed in 38 inpatients with a DSM-IV diagnosis of schizophrenia. Insight was assessed with the Scale to assess Unawareness of Mental Disorder (SUMD).

Results: A principal component analysis of the insight dimensions revealed a three-factor model which accounted for 98% of the variance. Of particular interest is the finding that a composite factor that accounted for 74% of the variance covered insight dimensions that represent a higher degree of insight (awareness of mental disorder, its social consequences, and attribution of symptoms). Only an association between letter fluency and this composite factor was found, which was weakly mediated by depressive symptoms. A stepwise multiple regression analysis revealed a relationship between antipsychotic dose and awareness of medication effect. No association of illness duration and insight was found.

Conclusions: The findings of partial association between dimensions of insight and measures of executive function supports the growing evidence that insight is a multidimensional phenomenon. Accordingly, they emphasise that in the framework of therapeutic interventions, enhancement of higher levels of insight needs to take into account that patients suffering from schizophrenia have differential impairment in insight dimensions.