Impact of Lurasidone on Metabolic Parameters and Prolactin Levels Based on Differences of Psychiatric Diagnosis, Dosage, and Introducing Methods: An Observational Study

Objective: Lurasidone is a second-generation antipsychotic (SGA) that contributes an antipsychotic and antidepressant effect, with low incidences of metabolic-related diseases and hyperprolactinemia for the treatment of psychological disorders. However, evidence on lurasidone is limited in psychiatric clinical settings. This study aimed to investigate the effect of short-term lurasidone treatment on metabolic effects and prolactin (PRL) levels, in relation to the differences of psychiatric disorders, lurasidone dosages, and introducing methods, in 35 female and 12 male Japanese inpatients with psychiatric disorders.

Methods: Subjects were placed into six subgroups divided by three categories (schizophrenia/schizoaffective disorder or bipolar disorder, 20mg/day or 40mg/day, adding or switching). Sequential changes in 10 items of metabolic parameters, including estimated insulin resistance and PRL levels at one month, were evaluated. The variations of metabolic parameters that were significantly changed from baseline were analyzed against sample characteristics and other metabolic parameter variations.

Results: In the 40mg/day and switching introduction method groups, lurasidone significantly reduced body weight, body mass index (BMI), levels of alanine amiotransaminase, and levels of fasting blood glucose. PRL levels seemed to increase when lurasidone was added and decrease when lurasidone was switched to from other antipsychotics. Switching introduction method and higher dosage correlated with weight loss and lowering fasting blood glucose levels, respectively.

Conclusion: Lurasidone administration offered the potential for weight loss, lowered serum blood glucose levels, and converging serum PRL concentrations. Moreover, switching introduction method with higher dosages might alleviate basal metabolism and glucose homeostasis. Further prospective studies combining measurements of serum insulin and psychometric evaluation will help to confirm our conclusions.