Relationship between plasma levels of prolactin and the severity of negative symptoms in patients with schizophrenia

Abstract

Objective: The aim of this study was to evaluate the relationship between plasma levels ofprolactin and negative symptoms.Methods: One hundred fourteen patients with schizophrenia were included in this cross-sectional study. The patients were classified into groups with and without hyperprolactinemia.Plasma levels of prolactin and clinical features were compared between these groups.Results: Negative symptom scores in the group with hyperprolactinemia were significantlyhigher than in the non-hyperprolactinemic group. There was also a positive correlation betweenplasma levels of prolactin and negative symptom scores. However, there was no statisticallysignificant difference between schizophrenia subtypes with regard to plasma prolactin levels.Patients treated with conventional neuroleptics or novel antipsychotics such as risperidone,paliperidone and amisulpride had higher prolactin levels than patients treated with aripiprazole,olanzapine, quetiapine, ziprasidone, and clozapine.Conclusion: This study indicated that we should be aware of prolactin levels, especially whennegative symptoms are prominent in patients with schizophrenia. Plasma levels of prolactincould be an important biological marker for the severity of negative symptoms in the treatmentof patients with schizophrenia. Thus, this finding may change the present pharmacotherapy fornegative symptoms in schizophrenia based on prolactin levels.