Sex Differences in the Effect of Atypical Antipsychoticson QTc Interval in Patients with Schizophrenia

CHEN Li-jun; ZHOU Qun

Abstract：Objective:To study sex differences in the effect of olanzapine(OLZ),risperidone(RIS),aripiprazole(ARP),or quetiapine(QTP) on mean corrected QT (QTc) intervals among 202 patients with schizophrenia.Method:Subjects were patients with schizophrenia who were treated with either OLZ(n=55), RIS (n=51),ARP (n=58),or QTP(n=38). Electrocardiographic measurements were conducted,and the QT interval was corrected using Bazett’s correction formula. Result:The mean QTc interval of the QTP group was significantly longer than that of the RIS group(P<0.05) or ARP group(P<0.05). The mean QTc interval of the OLZ group was also significantly longer than that of the RIS group(P<0.05).In female participants,the difference in the mean QTc interval among the four second-generation antipsychotic groups was statistically significant(P<0.05),whereas in male patients,there was no significant difference in the mean QTc interval among the four SGA groups(P>0.05). Post hoc analyses show that sex differences in QTc interval were observed only in OLZ treatment group(P<0.05). Conclusion:The OLZ and QTP treatment had a greater impact on the QTc interval compared with RIS or ARP. These effects are evident especially in female participants.