Prepulse inhibition deficits in antipsychotic-na-ve first-episode schizophrenia:a meta-analysis

Objective:Published studies have found prepulse inhibition(PPI)in schizophrenia is impaired,suggesting PPI may be a biomarker of schizophrenia.We aim to examine whether PPI deficits exist in antipsychotic-na-ve,first-episode schizophrenia,and evaluate the effect size of PPI deficits between patients and healthy controls.Methods:The effect size of PPI deficits was evaluated for PPI%by calculating standard mean differences(SMDs)between patients with antipsychotic-na-ve,first-episode schizophrenia and healthy controls.Results:Twelve studies met the inclusion criteria,consisting390antipsychotic-na-ve,first-episode schizophrenia and406healthy controls.The effect sizes of76dB PPI in60ms and120ms interstimulus interval(ISI)were-0.19and-0.41respectively,and the76dB PPI overall effect size was-0.30.The effect sizes of85/86dB PPI in30ms,60ms and120ms ISI were-0.25,-0.42and-0.59respectively,and the85/86dB PPI overall effect size was-0.46.One study were excluded due to heterogeneity in the85/86dB,120ms ISI group,the pooled effect size of the PPI differences between patient group and health control dropped to-0.42,and the overall effect size changed to-0.39.There were no statistical differences in startle magnitude(overall effect size=-0.18)and habituation%(overall effect size=-0.17)between patients and healthy controls.Conclusions:Antipsychotic-na-ve,first-episode schizophrenia patients exhibit robust and reliable deficits in PPI,85/86dB PPI deficit was more severe than76dB PPI,and85/86dB,60-ms ISI PPI was more likely to be a biomarker for schizophrenia,it suggested that the parameters of PPI are particularly significant to affect the effect size so that should be interpreted with cautions in the future studies.