Correlation between changes in quality of life and symptomatic improvement in Chinese patients switched from typical antipsychotics to olanzapine

Abstract

William Montgomery,1 Zbigniew Kadziola,2 Wenye Ye,3 Hai Bo Xue,4 Li Liu,4 Tamás Treuer5 1Global Patient Outcomes and Real World Evidence, Eli Lilly Australia Pty Ltd, West Ryde, NSW, Australia; 2Real World Analytics Capabilities, Eli Lilly GmbH, Vienna, Austria; 3Real World Analytics, Eli Lilly and Company, Indianapolis, IN, USA; 4Lilly Suzhou Pharmaceutical Company, Ltd, Shanghai, People’s Republic of China; 5Neuroscience Research, Eli Lilly and Company, Budapest, HungaryPurpose: The aim of this study was to investigate the correlation between changes in symptoms and changes in self-reported quality of life among Chinese patients with schizophrenia who were switched from a typical antipsychotic to olanzapine during usual outpatient care. Patients and methods: This post hoc analysis was conducted using data from the Chinese subgroup (n=475) of a multicountry, 12-month, prospective, noninterventional, observational study. The primary publication previously reported the efficacy, safety, and quality of life among patients who switched from a typical antipsychotic to olanzapine. Patients with schizophrenia were included if their symptoms were inadequately controlled with a typical antipsychotic and they were switched to olanzapine. Symptom severity was measured using the Brief Psychiatric Rating Scale (BPRS) and the Clinical Global Impressions-Severity scale (CGI-S). Health-Related Quality of Life (HRQOL) was assessed using the World Health Organization Quality of Life–Abbreviated (WHOQOL-BREF). Paired t-tests were performed to assess changes from baseline to endpoint. Pearson’s correlation coefficients (r) were used to assess the correlations between change in symptoms (BPRS and CGI-S scores) and change in HRQOL (WHOQOL-BREF scores). Results: Symptoms and HRQOL both improved significantly over the 12 months of treatment (P<0.001). Significant correlations were observed between changes from baseline to end of study on the BPRS and the CGI-S and each of the WHOQOL-BREF four domain scores and two overall quality-of-life questions. The correlation coefficients ranged from r=−0.45 to r=−0.53 for the BPRS and WHOQOL-BREF. The correlation coefficients were slightly smaller between the CGI-S and WHOQOL-BREF, ranging from r=−0.33 to r=−0.40.Conclusion: For patients with schizophrenia, assessing quality of life has the potential to add valuable information to the clinical assessment that takes into account the patient’s own perspective of well-being. Keywords: data correlation, olanzapine, quality of life, schizophrenia, signs and symptoms