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Factors associated with subjective side-effects during clozapine treatment
Niko Seppälä1, Esa Leinonen, Merja Viikki
1Niko Seppälä, Department of Psychiatry, Satakunta Hospital District, University of Tampere , FI-29200 Harjavalta , and Medical School, Faculty of Medicine, University of Tampere , FI-33140 Tampere , Finland.
Objective:
Clozapine is associated with subjectively unpleasant or clinically serious side-effects, which may affect treatment adherence. The aims of the study were to explore the association of clozapine+ norclozapine serum concentration and other factors with subjective side-effects in schizophrenia patients.
Methods:
In this cross-sectional study, 237 patients with a diagnosis of schizophrenia, schizo-affective or other non-organic psychoses completed the Liverpool University Neuroleptic Side Effect Rating Scale (LUNSERS), a self-report scale measuring side-effects of antipsychotics and a clinical questionnaire. Clozapine+ norclozapine serum concentration of 190 patients was measured. Of the patients 80 (33.7%) were on antipsychotic combination therapy.
Results:
Higher clozapine+ norclozapine concentrations were associated with the depression-anxiety factor of LUNSERS and antipsychotic combination treatments were associated with sympatichotonia-tension factor. Younger patients reported sedation more often than older patients.
Conclusion:
According to the present results, high clozapine concentrations were associated with depression-anxiety symptoms, but the causality remains unknown.
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