Lack of Correlation of Continuous Performance Test with Plasma Levels of Haloperidol in Patients with Schizophrenia

Abstract

Objective: The relationship between high dosages of antipsychotic and the development of cognitive deficits requires further investigation. The aim of this study was to examine the correlation between Continuous Performance Test (CPT) and plasma level of haloperidol in patients with schizophrenia. Methods: Eight patients with schizophrenia, including four males and four females, who had been taking haloperidol for more than one year were enrolled. Subject responses were recorded automatically using the CPT machine on the day of blood sampling. The plasma concentration of haloperidol was determined by liquid chromatography-tandem mass spectrometry (LC/MS/MS). Results: No correlation was found between the CPT results and plasma levels of haloperidol. Conclusion: CPT score might be a stable vulnerability indicator for schizophrenia. The plasma level of haloperidol may not affect CPT performance directly.