Impact of olanzapine on quality of life of patients with schizophrenia: one-year follow-up with the Seville Quality of Life Questionnaire

Abstract

Introduction. Our objetive is to present the impact on quality of life of long-term olanzapine treatment in a significant number of schizophrenics as determined by the Seville Quality of Life Questionnaire (SQLQ), an instrument that addresses the aspects that particularly affect these patients, and to evaluate the sensitivity of this instrument to the changes induced by this treatment.

Methods. Three hundred and seventy two patients with the diagnosis of schizophrenia as per the ICD-10 classification were evaluated in a 1 year prospective study after switching to olanzapine. The SQLQ, Lehman's structured interview and short version of the discapacity assessment scale were used to evaluate patient's subjective experience; in addition, other instruments were used to evaluate psychopathology.

Results. Significant increases in the scores of the favorable scale and decreases in the unfavorable scale of the SQLQ were found. There were also significant improvements in quality of life as measured with Lehman's structured interview. This improvement continued until the end of the 1 year follow-up after switching to olanzapine. Both instruments show a good correlation. Changes in psychopathology were also remarkable, including the negative symptoms.

Conclusions. The SQLQ has proven to be a sensitive instrument to measure quality of life in schizophrenic patients treated with olanzapine. It focuses on aspects that are relevant for patients that were frequently overlooked by treating physicians. This drug has been proven to have a favorable subjective impact upon patients, besides improving psychopathology.