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 k nown about the possible relationship of concurrent mood symptoms and qualit y of life. We hypothesized that the quality of life for people with schizop hrenia would be inversely related to the severity of concurrent mood disrup tion. Method: We conducted a post hoc analysis of an international, multice nter, double-blind, 28-week study of 339 patients who met DSM-IV criteria f or schizophrenia, schizophreniform, or schizoaffective disorder and were ra ndomized to treatment with either olanzapine of risperidone. Quality of lif e data were collected at baseline, 8, 16, 24, and 28 weeks or at early disc ontinuation; Positive and Negative Syndrome Scale (PANSS) data were collect ed at each visit (weekly to week 8 and monthly thereafter). Correlations we re calculated between changes in quality of life (quality of life scale [QL S] total and subscales) and PANSS mood score. Regression models were used t o determine the proportion of variability in the QLS total and subscores ac counted for by changes in PANSS positive, PANSS negative, and PANSS mood sc ores. Finally, path analysis was performed to determine the mechanisms used by the PANSS mood scores to affect the QLS total and subscores. Results: O lanzapine demonstrated a significantly greater therapeutic effect on the PA NSS mood item than risperidone did. However, mood improvements with either therapy demonstrated correlations of PANSS mood on the QLS total and subsco res which were statistically significant, with the strongest correlation ag ainst the interpersonal relations (QLS-IPR) subscore. The path analysis res ults indicate that the PANSS mood item's most significant path 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 conc urrent mood disruption. Early therapeutic interventions directed at a broad er constellation of schizophrenic symptomatology, including mood, may be he lpful in improving an individual patient's quality of life. The possible re lative advantages of introducing novel antipsychotic agents earlier in the course of illness for restoration of individual quality of life merit furth er investigation.