Various effects of antipsychotics on P50 sensory gating in Chinese schizophrenia patients: a meta-analysis.

Background: The aim of this study was to conduct a meta-analysis so we could evaluate the impact of antipsychotics on the P50 ratio in Chinese schizophrenia patients.
Methods: Data were collected from the following databases: PubMed, China Biological Medicine Database, China National Knowledge Infrastructure, Cochrane Library and Elsevier Science Direct, with the latest report up to May 2011. An effect size with a 95% confidence interval (CI) was used to assess the strength of various effects of antipsychotics on P50 ratio in the patients.
Results: A total of six studies including 315 and 285 schizophrenia patients at the baseline and endpoint, respectively. Overall, no significant effect of these medicines on the P50 ratio was found (overall effect z=1.03, p=0.30; heterogeneity: Chi2=2.81, df=8, p=0.95, I2=0%). In subgroup analysis by drug, we did not find any significant effects on P50 ratio in either first-generation antipsychotics (effect z=0.92, p=0.36; heterogeneity: Chi2=0.00, df=1, p=0.98, I2=0%) or second-generation antipsychotics (effect z=0.55, p=0.58; heterogeneity: Chi2=2.38, df=5, p=0.79, I2=0%).
Conclusion: Our meta-analysis suggests that neither the first-generation nor the second-generation antipsychotics had any significant effects on P50 ratio in Chinese patients with schizophrenia.