Relationships Between Cognitive Deficits, Symptoms and Quality of Life in Schizophrenia

Abstract
Objective: Schizophrenia is a complex disorder characterized by impairment in a number of domains, all of which contribute to disability. The aim of the present study was to investigate the relationships between cognitive function, symptoms and quality of life (QOL) in schizophrenia. Method: This cross-sectional study measured cognition, positive and negative symptom severity, and quality of life (measured with the Quality of Life Scale) in 57 outpatients with schizophrenia. Correlations between the different measures were sought. Multiple regression analyses were used to develop models of the contributions of cognitive deficits and symptomatology to QOL. Results: More severe positive and negative symptoms and cognitive impairment each correlated with poorer QOL. There was a moderate association between negative symptoms and cognition and a small association between positive symptoms and cognition. Age, gender, and drug and alcohol abuse did not significantly predict QOL. In the multiple regression analysis, entering the total cognition and total symptom scores produced a model that accounted for an additional 57% of the variance in QOL. Conclusions: Improving quality of life for people with schizophrenia requires that positive and negative symptoms and cognition are each addressed as separate domains of impairment. But, given that these account for only 57% of the variance in QOL, other factors such as unemployment, poverty, social isolation and stigma may also be important.