Prolactin, a polypeptide hormone secreted by lactotroph cells of the anterior pituitary gland, is involved in many biological functions including reproduction, pregnancy, and lactation. A variety of studies over the past four decades have examined other facets of the relationship between prolactin and schizophrenia and call for a reappraisal of this relationship. Some recent studies have found increased prolactin concentrations in antipsychotic-naive psychotic patients, whereas other studies of previously treated but drug-free patients reported concentrations that are normal or lower than those in controls.Objective
The aim of this study was to determine whether there is a significant rise in serum prolactin in psychotropic drug-naive male patients with first-episode schizophrenia related to disease process and its correlation with psychopathology.Patients and methods
Thirty male patients with first-episode schizophrenia were included in this cross-sectional study. Patients were drug-free and psychotropic drug-naive. The patients were classified into two groups: those with and those without hyperprolactinemia. Plasma levels of prolactin and demographic and clinical characteristics were compared between these groups. Standardization for control was carried out using 30 control plasma prolactin samples obtained from healthy individuals. Methodology involved assessment by means of radioimmunoassay. For schizophrenic patients, clinical evaluation was carried out by measuring the Premorbid Adjustment Scale (PAS), the Positive and Negative Syndrome Scale, and the Montgomery–Asberg Depression Rating Scale. The scores for these scales were significantly higher in the hyperprolactinemia group than in the nonhyperprolactinemic group.Results
Serum prolactin level was elevated at baseline in 46.7% of first-episode schizophrenic patients. Duration of untreated psychosis and poor premorbid adjustment (PAS) were significantly higher in the group with hyperprolactinemia than in the nonhyperprolactinemic group. In addition, total Positive and Negative Syndrome Scale scores, negative symptom scores, and Montgomery–Asberg Depression scores in the group with hyperprolactinemia were significantly higher than that in the nonhyperprolactinemic group. There was also a positive correlation between plasma levels of prolactin and duration of untreated psychosis, PAS, negative symptom scores, and Montogomery–Asberg Depression scores.Conclusion
This study suggests that we should be aware of prolactin levels in first-episode schizophrenic patients, especially when negative and depressive symptoms are prominent. Thus, this finding may change the present pharmacotherapy for negative and depressive symptoms in schizophrenia based on prolactin levels.