Potential Mitigation of Olanzapine-induced Derangement of Blood Sugars by Adding Aripiprazole to the Therapeutic Regimen of patients with Schizophrenia: A Follow-up Study

Abstract

Shahad M. Khaleel, Musab M. Khalaf, Mahfoth S. Hasan

Several reports have linked the use of antipsychotics such as clozapine and olanzapine with dyslipidemia, insulin insensitivity, derangement of glucose metabolism and an increase in body weight. Comparing to other antipsychotics, aripiprazole have better efficacy and better side effect profile, so we wanted to investigate whether the disturbances in BMI and glycemic control caused by olanzapine can be mitigated by the addition of aripiprazole to olanzapine therapy over 8 weeks of use. A follow-up case series study design was adopted in this study. Out of 36 patients recruited, 29 patients (17 males, 12 females) completed it. Prior to the enrollment in this work, olanzapine was taken by these patients at dose 10 mg/day for at least 3 months duration. After enrollment, aripiprazole then added to olanzapine at dose of 10 mg/day and the combination used regularly for 8 weeks.Fasting blood glucose (FBG), fasting serum insulin (FSI), C-peptide,glycated hemoglobin(HbA1C), the homeostatic model assessment for insulin resistance (HOMA-IR) and BMI were measured at baseline and at the end ofcombination therapy.The obtained results showed that, aripiprazole adjunctive therapy to olanzapine caused a significant decline in BMI, FBG, HbA1C.Yet, no significant change was observed in FSI and HOMA-IR.A significant elevation in C-peptide levels were also observed following 8 weeks of combination therapy in comparison with baseline. In conclusion,olanzapine and aripiprazole combinationtherapy can improve several parameters relatedto glycemic control and insulinresistance which may underlie reduce body weight in schizophrenicpatients managed witholanzapine