Is quality of life associated with cognitive impairment in schizophrenia?

BACKGROUND: The subjectively assessed quality of life of schizophrenia patients is mostly lower than healthy subjects, and cognitive impairment is an integral feature of schizophrenia. The aims of the present study were to compare the quality of life and neurocognitive functioning between the patients with schizophrenia and the healthy subjects, and to examine the relationships between quality of life and neurocognitive functions among the patients with schizophrenia. METHODS: Thirty-eight patients with schizophrenia (15 women and 23 men) and 31 healthy individuals (18 women and 13 men) were included in the study. All participants were administered World Health Organization Quality of Life-Brief Form (WHOQOL-BREF) to assess their quality of life, and Digit Span Test (DST) and Controlled Oral Word Association Test (COWAT) for cognitive functions. RESULTS: The patients with schizophrenia demonstrated lower scores in physical (F=25.6, p=0.0001), psychological (F=15.85, p=0.0001) and social (F=37.7, p=0.0001) domains compared to control group. The patients with schizophrenia showed significantly lower scores on COWAT compared to healthy subjects (F=4.22, p=0.04). The social domain scores of WHOQOL correlated to DST total scores (r=0.45, p=0.007), DST forwards scores (r=0.54, p=0.001) and COWAT total scores (r=0.40, p=0.04) in patients with schizophrenia but not in the control group. The patients with lower level of cognitive functioning had lower scores on social domain of WHOQOL-BREF (z=-2.01, p=0.04). CONCLUSION: Our results confirm that the cognitive deficits in executive function and working memory appear to have direct impact on the patients' perceived quality of life especially in social domain which can either be a cause or a consequence of social isolation of patients with schizophrenia.