Relationship between Clozapine-Induced Electroencephalogram Abnormalities and Serum Concentration of Clozapine in Japanese Patients with Treatment-Resistant Schizophrenia
- Author:
Yuka Sugawara KIKUCHI
1
;
Takashi KANBAYASHI
;
Tetsuo SHIMIZU
Author Information
- Publication Type:Original Article
- Keywords: Serum clozapine concentration; Electroencephalography abnormalities; Treatment-resistant schizophrenia
- MeSH: Asian Continental Ancestry Group; Clozapine; Electroencephalography; Humans; Male; Schizophrenia
- From:Psychiatry Investigation 2019;16(4):279-284
- CountryRepublic of Korea
- Language:English
- Abstract: OBJECTIVE: The objective of this study was to investigate the relationship between the serum concentration of clozapine (C-CLZ), N-desmethylclozapine (N-CLZ) and the daily dose of CLZ (D-CLZ), and the relationships among CLZ and electroencephalogram (EEG) abnormalities. METHODS: Twenty-eight patients were recruited to this study, but 8 patients were excluded because clozapine was discontinued before the post-treatment measurement of EEG or C-CLZ. Ultimately, 20 patients (6 men, 14 women) with an average age of 36 years were enrolled. The subjects were divided into EEG normal and abnormal groups. C-CLZ and N-CLZ were measured at 4, 12, 26, and 52 weeks after initiating CLZ administration. RESULTS: All patients had normal baseline EEG signals, and 8 patients showed EEG abnormalities later. There were significant correlations between C-CLZ and D-CLZ, and between N-CLZ and D-CLZ. The C-CLZ/D-CLZ, N-CLZ/D-CLZ, and C-CLZ/N-CLZ ratio were not significantly different between the EEG normal and EEG abnormal groups. The EEG abnormal group had significant higher proportion of patients with high intra-individual variability in their C-CLZ/D-CLZ ratio. CONCLUSION: There is no relationship between C-CLZ and EEG abnormalities. However, patients with high intra-individual variability in their C-CLZ/D-CLZ ratio had greater possibility of exhibiting EEG abnormalities.
