The effects of quetiapine and aripiprazole on platelet 5-HT concentrations in patients with schizophrenia

Abstract

Objective To study the effects caused by novel antipsychotics quetiapine and aripiprazole on concentrations of platelet 5-HT in patients with schizophrenia,and to explore the relationships among the change of platelet 5-HT concentrations, psychiatric symptoms and the sensitivity of therapy. Methods Sixty-eight patients with schizophrenia meeting International Classification of Diseases-10 (ICD-10) were enrolled in the study. They were divided into quetiapine group(n=34) and aripiprazole group(n=34) according to the sequence of admis-sion. The platelet 5-HT concentrations were measured with high performance liquid chromatography method(HPLC-ECD). The positive and negative syndrome scale (PANSS) was used to evaluate the psychopathology. Treatment emergent symptom scale (TESS) was used to evaluate the side effects. PANSS,TESS were used at pre-treatment,the end of 4th and 8th week of treatment. Results The platelet 5-HT concentrations in two groups were higher af-ter 8 weeks treatment,but had no statistically significant difference (P>0.05). In quetiapine group, the platelet 5-HT concentration was (458.89±233.36) ng/10~9 at the pre-treatment, and (554.31±313.22) ng/10~9 at the end of treatment (t=1.709, P=0.099). In aripiprazole group, the platelet 5-HT concentration was (409.83±149.32)ng/10~9 at the pretreatment, and (421.27±245.96)ng/10~9 at the end of treatment (t=0.321, P=0.819). There was no difference between two groups(P>0.05). Stepwise regression analysis showed the changing rate of platelet 5-HT concentrations was positively correlated with the dosage of quetiapine (r=0.385, P=0.039).It was positively correlated with the decreasing rate of PANSS in aripiprazole group(r=0.391, P=0.040). Con-dusion The changes of psychiatric symptoms and the dosages of antipsychotics maybe have intimate relationships with platelet 5-HT concentrations in the course of medication. Key words: Schizophrenia ; Quetiapine ; Aripiprazole ;