The Effect of Sudden Clozapine Discontinuation on Management of Schizophrenic Patients: A Retrospective Controlled Study.

Background: The aims of our study were (1) to compare the dose of clozapine needed to achieve remission in patients who stopped their treatment (study group) versus patients who continued taking this medication (control group) and (2) to compare the clinical characteristics of remission between these 2 groups.

Method: We retrospectively reviewed the medical records of all treatment-resistant schizophrenic and schizoaffective patients (according to DSM-IV criteria) who were treated with clozapine over a period of 9 years, from January 1995 through December 2003. The study group consisted of 43 patients and the control group of 12 patients. All patients' files from both groups were examined, and each patient's remission was scored twice initially on discharge from the hospital and subsequently after final discharge for the study group, or at the end of the study for the control group.

Results: The change of clozapine dose from the first to the last remission expressed by percentage shows a significant difference between the 43% increase in clozapine dose in the study group and the 12.5% decrease in clozapine dose in the control group (p < .001). Quality of remission assessment showed deterioration in the global remission score in the study group, while the quality of remission assessment in the control group did not show any change.

Conclusions: Our findings suggest that the discontinuation of clozapine treatment leads to a deterioration in the quality of remission, with a need for an increased dose of clozapine. Further prospective studies on larger samples are needed to confirm these findings.

J Clin Psychiatry 2006;67(8):1204-1208