The effects of clozapine on cognitive function and regional cerebral blood flow in the negative symptom profile schizophrenia.
OBJECTIVE
Cognitive function and regional cerebral blood flow (rCBF) were studied in negative symptom profile schizophrenic patients by using WCST and SPECT.


METHODS
Twenty-one schizophrenic patients who matched the criteria of Andreason's negative symptom profile received SPECT and WCST, and then were treated with clozapine for 8 consecutive weeks. There were 28 and 12 normal subjects as the control groups of WCST and SPECT, respectively.


RESULTS
Compared with controls, significantly poorer performance on total trials of category (TT), persevering errors (PE), and non-persevering errors (NPE) of WCST were found in schizophrenia (p < 0.05). The total score of the scale for assessment negative symptoms (SANS) was significantly related with poor TT (r = 0.45, p < 0.01) and PE performance (r = 0.45, p < 0.01). The poor TT, PE, and NPE tasks of WCST and SANS scores in the negative schizophrenic patients were significantly improved through clozapine treatment (p < 0.05). The schizophrenic patients had a significantly lower rCBF in bilateral frontal and temporal lobes and lower change rate of rCBF in bilateral frontal lobes during WCST compared to normal controls (p < 0.05).


CONCLUSIONS
Negative symptom profile schizophrenia has cognitive deficits and lower rCBF in bilateral frontal and temporal lobes, which suggests that negative symptom profile schizophrenic patients have hypofrontality. Clozapine can improve negative symptoms and improve cognitive dysfunction, although it cannot improve reduced rCBF in the frontal lobes.
Zhao
Jingping
J
Department of Psychiatry, Second Xiangya Hospital, Central South University, Hunan, China. zjpliu6@public.cs.hn.cn
He
Xiaolin
X
Liu
Zhening
Z
Yang
Desen
D
D000328:Adult; D014150:Antipsychotic Agents / Q000009:adverse effects / Q000627:therapeutic use*; D002531:Cerebellum / Q000098:blood supply; D003024:Clozapine / Q000009:adverse effects / Q000627:therapeutic use*; D003072:Cognition Disorders / Q000175:diagnosis / Q000188:drug therapy*; D003863:Depression / Q000175:diagnosis / Q000188:drug therapy*; D004292:Dominance, Cerebral / Q000187:drug effects / Q000502:physiology; D005260:Female; D005625:Frontal Lobe / Q000098:blood supply*; D006801:Humans; D008297:Male; D009483:Neuropsychological Tests; D009778:Occipital Lobe / Q000098:blood supply; D010296:Parietal Lobe / Q000098:blood supply; D012016:Reference Values; D012039:Regional Blood Flow / Q000187:drug effects; D012559:Schizophrenia / Q000175:diagnosis / Q000188:drug therapy*; D013702:Temporal Lobe / Q000098:blood supply*; D015899:Tomography, Emission-Computed, Single-Photon; D016896:Treatment Outcome
D014150:Antipsychotic Agents; D003024:Clozapine