Second-generation antipsychotics activate platelets in antipsychotic-naive and antipsychotic-free patients with schizophrenia: A retrospective study

Objective Among the risk factors for cerebrovascular/cardiovascular disease or thromboembolic events caused by the administration of second-generation antipsychotics, clinicians have mainly focused on metabolic side effects, with little interest in the effects on platelet activity. Because excessive platelet activity can increase the risk for cerebrovascular/cardiovascular disease, the aim of this study was to investigate the effect of second-generation antipsychotics on platelet activity in patients with schizophrenia. Methods The medical records of patients with schizophrenia who were treated with second-generation antipsychotics were retrospectively reviewed. The degree of platelet activation was assessed by measuring the mean platelet component. Results Wilcoxon signed-rank test revealed that mean platelet component levels were significantly decreased by the administration of second-generation antipsychotics (V = 20; p < 0.05), suggesting that the administration of second-generation antipsychotics may increase platelet activation. Conclusion Because platelet activation is an additional risk factor for the occurrence of cerebrovascular/cardiovascular disease, results of this study suggest that clinicians should carefully monitor the degree of platelet activation after the administration of second-generation antipsychotics.