Factors Influencing Blood Prolactin Levels in Patients with Schizophrenia under Risperidone Treatment

Abstract

Abstract Objectives: Risperidone, a dopamine and serotonin antagonist or a second-generation (atypical) antipsychotic drug, is commonly prescribed for various psychiatric disorders, including schizophrenia, bipolar disorder, and autism spectrum disorders. While effective, risperidone often leads to hyperprolactinemia, impacting about 40%–80% of patients. In this study, we intended to examine the prevalence of hyperprolactinemia in Taiwanese patients with schizophrenia who received risperidone medication and to analyze potential links between prolactin blood levels and clinical variables. Methods: Patients with schizophrenia receiving risperidone monotherapy were included in this cross-sectional study. Blood levels of prolactin and metabolic parameters were measured. Results: A total of 176 participants diagnosed with schizophrenia, including 87 women and 89 men, were enrolled in our study. The prevalence of hyperprolactinemia and metabolic syndrome was 75.6% and 31.8%, respectively. Patients with hyperprolactinemia showed significantly higher insulin blood levels (p < 0.05) and significantly higher homeostasis model assessment for insulin resistance (HOMA-IR) indexes (p < 0.05) than those without hyperprolactinemia. The results of multivariate linear regression analysis showed that female sex (p = 0.001), HOMA-IR index (p < 0.01), and risperidone daily dosage (p < 0.05) were significantly associated with prolactin blood level. Conclusion: This study adds to the existing knowledge concerning risperidone-induced hyperprolactinemia in Taiwanese patients with schizophrenia. Hyperprolactinemia and metabolic syndrome are prevalent in patients with schizophrenia treated with risperidone. Clinicians are advised to be aware of these problems and monitor them regularly with their patients who receive treatment with risperidone.