Evaluation of Clinical Correlation between Insulin Resistance and Antipsychotic Drug Therapy in Patients with Schizophrenia

Background: Treatment with different antipsychotics can lead to various metabolic side effects in patients with psychosis, impacting long-term prognosis. This study aimed to compare the changes and clinical efficacy of insulin resistance in patients treated with olanzapine and ziprasidone. Method: A retrospective analysis was conducted on the clinical data of 80 patients with schizophrenia. The patients were divided into olanzapine treatment group and ziprasidone treatment group. Parameters including body weight, body mass index (BMI), fasting plasma glucose (FPG), fasting plasma insulin (FPI), cholesterol (CHO), triglyceride (TG), high-density lipoprotein (HDL), low-density lipoprotein (LDL), insulin resistance index, and Positive and Negative Syndrome Scale (PANSS) scores were recorded and compared before and after treatment. Results: BMI, FPG, FPI, homeostatic model assessment of insulin resistance (HOMA-IR), CHO, TG and LDL in both groups were significantly higher than before treatment (p < 0.05). These parameters were significantly higher in the olanzapine group than in the ziprasidone group (p < 0.05). The level of HDL in both groups was significantly decreased after treatment, and the level of HDL in the olanzapine group was significantly lower than that in the ziprasidone group after treatment (p < 0.05). After treatment, the total score and score of PANSS in both groups were significantly lower than before treatment (p < 0.05). After treatment, there was no significant difference in total score and PANSS score between both groups (p > 0.05). The incidence of insulin resistance (IR) was significantly higher in the olanzapine group compared to the ziprasidone group (chi(2) = 4.021, p < 0.05). In the IR group, BMI, FPG, FPI, TG, and LDL levels were higher than in the non-IR group (p < 0.05). Multivariate analysis indicated that BMI, FPG, FPI, TG, and LDL were independent risk factors for IR (odd ratio (OR) >1, p < 0.05). Conclusions: Treatment with olanzapine and ziprasidone improves clinical symptoms in patients with schizophrenia, but increases the risk of insulin resistance. The metabolic side effects of olanzapine are more pronounced.