Platelet glutamate dehydrogenase activity and efficacy of antipsychotic therapy in patients with schizophrenia.

Abstract

Evaluation of possible relationship between platelet glutamate dehydrogenase (GDH) activity and mental state of schizophrenia patients after antipsychotic pharmacotherapy. Patients (n = 50) with chronic paranoid schizophrenia (F20.0) initially in acute psychotic state were examined before and after a treatment course with antipsychotics. When assessing the patients' states using PANSS, the "responder" category was attributed to those patients who had not less than 30% reduction in the score for the corresponding PANSS "subscale". The control group (n = 48) was ageand gender-matched with the patient group. Platelet glutamate dehydrogenase (GDH) activity was measured in patients twice, before and after the treatment course, and once in controls. Significantly reduced GDH activity was found in patients compared with controls. The patient group was divided into two subgroups according to median GDH activity at baseline: above and below the median GDH, subgroup 1 and subgroup 2, respectively. GDH activity significantly increased from its level at baseline after antipsychotic treatment in subgroup 2. Distribution of non responders / responders to antipsychotic treatment (by PANSS scores) was significantly uneven among subgroups 1 and 2. In subgroup 1, GDH activity levels significantly correlated with PANSS scores after the treatment course. Baseline platelet GDH activity might serve as a predictor of antipsychotic therapy efficacy in schizophrenia patients.