Effect of buspirone, a serotonin1A partial agonist, on cognitive function in schizophrenia: a randomized, double-blind, placebo-controlled study.
In previous studies, we demonstrated that tandospirone, a serotonin-5-HT1A partial agonist, added to ongoing treatment with small to moderate doses of typical antipsychotic drugs, improved executive function and verbal learning and memory. However, tandospirone is not available in most countries, and atypical antipsychotic drugs (AAPDs) have largely replaced typical antipsychotic drugs as the primary treatment for schizophrenia. Therefore, the goal of this randomly assigned placebo-controlled double-blind study was to determine if the addition of buspirone, a widely available 5-HT1A partial agonist, would enhance cognitive function, in subjects with schizophrenia treated with AAPDs. Seventy-three patients with schizophrenia, who had been treated with an AAPD for at least three months, were randomly assigned to receive either buspirone, 30 mg/day, or matching placebo. All other medications remained unchanged. Attention, verbal fluency, verbal learning and memory, verbal working memory, and executive function, as well as psychopathology, were assessed at baseline, and 6 weeks, and 3 and 6 months after baseline. A significant Time x Group interaction effect was noted on the Digit Symbol Substitution Test, a measure of attention/speeded motor performance, due to better performance of the buspirone group compared to the placebo group at 3 months. No significant interaction effects were noted for other domains of cognition. Scores on the Brief Psychiatric Rating Scale (Total, Positive) were improved during treatment with buspirone but not placebo, but the effects did not reach statistical significance. The results of this study showed a possible benefit of buspirone augmentation of AAPDs to enhance attention. However, we did not replicate the results of the previous study with tandospirone, which may be due to the differences between tandospirone and buspirone, between typical antipsychotics and AAPDs, or a combination of the above. Further study to determine the usefulness of 5-HT1A agonist treatment in schizophrenia is indicated.
Sumiyoshi
Tomiki
T
Department of Neuropsychiatry, University of Toyama Graduate School of Medicine and Pharmaceutical Sciences, Toyama, Japan. sumiyo@med.u-toyama.ac.jp
Park
Sohee
S
Jayathilake
Karu
K
Roy
Ajanta
A
Ertugrul
Aygun
A
Meltzer
Herbert Y
HY
D000328:Adult; D000553:Ambulatory Care; D014150:Antipsychotic Agents / Q000627:therapeutic use; D002065:Buspirone / Q000627:therapeutic use*; D003072:Cognition Disorders / Q000175:diagnosis / Q000188:drug therapy* / Q000523:psychology; D004311:Double-Blind Method; D004359:Drug Therapy, Combination; D005260:Female; D006801:Humans; D054833:Isoindoles; D008297:Male; D009483:Neuropsychological Tests / Q000706:statistics & numerical data; D010879:Piperazines / Q000627:therapeutic use; D010919:Placebos; D011743:Pyrimidines / Q000627:therapeutic use; D012559:Schizophrenia / Q000175:diagnosis / Q000188:drug therapy*; D012565:Schizophrenic Psychology; D017366:Serotonin Receptor Agonists / Q000627:therapeutic use*; D016896:Treatment Outcome
D014150:Antipsychotic Agents; D054833:Isoindoles; D010879:Piperazines; D010919:Placebos; D011743:Pyrimidines; D017366:Serotonin Receptor Agonists; C055267:tandospirone; D002065:Buspirone