Effects of add-on mirtazapine on neurocognition in schizophrenia

• Main Author: Stenberg, Jan-Henry
• Other Authors: Hintikka, Jukka, University of Helsinki, Faculty of Medicine, Institute of Clinical Medicine, Department of Psychiatry, Helsingin yliopisto, lääketieteellinen tiedekunta, kliininen laitos, Helsingfors universitet, medicinska fakulteten, institutionen för klinisk medicin, Joffe, Grigori, Tiihonen, Jari
• Format: Doctoral or Postdoctoral Thesis
• Language: English
• Published: Helsingin yliopisto 2013
• Subjects: lääketiede; karelia*; karelian
• Online Access: http://hdl.handle.net/10138/42398

Schizophrenia is a severe, psychiatric illness with neurocognitive deficits as its major component, and affects about 1% of the world population. Improving impaired neurocognitive function is one of the pivotal treatment goals in this patient population. In the treatment of schizophrenia, only a partial treatment response is typically achieved with dopamine antagonists; i.e., antipsychotics . The antidepressant mirtazapine has a unique mechanism of action with, in theory, an ability to enhance neurocognition and provide added value to antipsychotic treatment. This study explored whether or not adjunctive mirtazapine has the potential to improve neurocognitive performance and alleviate clinical symptoms in patients with schizophrenia who demonstrated a suboptimal treatment response to first-generation antipsychotics (FGAs). This study was a neurocognitive arm of a single-center, randomized, add-on, double-blinded, placebo-controlled study, which was carried out in the Karelian Republic, Petrozavodsk, Russia. Patients with schizophrenia or a depressive type schizoaffective disorder, according to the Diagnostic and Statistical Manual of Mental and Behavioral Disorders 4th edition (DSM-IV) criteria, who received stable doses of FGA with inadequate treatment response were enrolled into the trial. Twenty patients were assigned to mirtazapine and 21 to placebo. After a one-week single-blind placebo run-in period, the participants were randomized to receive either 30 mg of mirtazapine or the placebo four times a day (QID) in a double-blind fashion for 6 weeks. Subsequently, those who were eligible to continue entered the following 6-week open-label phase, where they were treated with mirtazapine 30 mg QID. At study weeks 0, 6, and 12, a senior psychologist performed neuropsychological examinations to evaluate neurocognitive functioning. Verbal and visual memory, visuo-spatial and executive functions, verbal fluency and both general mental and psychomotor speeds were assessed by commonly used, validated ...