Should We Consider Mood Disturbance in Schizophrenia as an Important Determinant of Quality of Life?

Background: The main objective in the treatment of schizophrenia should be to optimize individual patient functioning and quality of life. Little is known about the possible relationship of concurrentmood symptoms and quality of life. We hypothesized that the quality of life for people withschizophrenia would be inversely related to the severity of concurrent mood disruption. Method: We conducted a post hoc analysis of an international, multicenter, double-blind, 28-week study of 339 patientswho met DSM-IV criteria for schizophrenia, schizophreniform, or schizoaffective disorder andwere randomized to treatment with either olanzapine or risperidone. Quality of life data were collectedat baseline, 8, 16, 24, and 28 weeks or at early discontinuation; Positive and Negative Syndrome Scale(PANSS) data were collected at each visit (weekly to week 8 and monthly thereafter). Correlationswere calculated between changes in quality of life (quality of life scale [QLS] total and subscales) andPANSS mood score. Regression models were used to determine the proportion of variability in theQLS total and subscores accounted for by changes in PANSS positive, PANSS negative, and PANSSmood scores. Finally, path analysis was performed to determine the mechanisms used by the PANSSmood scores to affect the QLS total and subscores. Results: Olanzapine demonstrated a significantly greater therapeutic effect on the PANSS mood item than risperidone did. However, mood improvementswith either therapy demonstrated correlations of PANSS mood on the QLS total and subscoreswhich were statistically significant, with the strongest correlation against the interpersonal relations(QLS-IPR) subscore. The path analysis results indicate that the PANSS mood item’s most significantpath in affecting the QLS total and QLS-IPR is direct. Conclusion: Changes in the quality of life of schizophrenic patients is inversely related to changes in the concurrent mood disruption. Early therapeuticinterventions directed at a broader constellation of schizophrenic symptomatology, includingmood, may be helpful in improving an individual patient’s quality of life. The possible relative advantagesof introducing novel antipsychotic agents earlier in the course of illness for restoration of individualquality of life merit further investigation.