Predicting quality of life impairment in chronic schizophrenia from cognitive variables

Background The aim of this study was to see whether and how cognition deficit predicts quality of life impairments in schizophrenia patients. Method The Computerized Cambridge Automated Neuropsychological Test Battery, the Quality of Life Enjoyment and Satisfaction Questionnaire (Q-LES-Q) and the Quality of Life Scale (QLS) were used to assess 62 patients with chronic schizophrenia. Step-wise multiple regression analysis was used in order to determine cognitive variables that would predict the scores of each Q-LES-Q and QLS domain scores. Results Regression analysis revealed a significant association of the cognitive deficits with both general and domain-specific quality of life impairment measured with Q-LES-Q and QLS. Deficits in executive functions, visual sustained attention, memory and motor skills have been found to be valid predictors both before and after controlling for the severity of symptoms, emotional distress, side effects, age, education, and illness duration. Conclusions This study suggests that deficits in executive functioning, attention, memory and motor skills substantially contributes to predicting impairments across a wide range of HRQL domains, and, consequently, to quality of life appraisal in schizophrenia. Cognitive predictors cannot be attributed to illness-related and background variables. It can be concluded that, when aiming at the improvement of quality of life in schizophrenia patients, cognitive functioning should be targeted.