[Correlation of the peripheral serum complement protein levels and cognitive function in first-episode drug-naive patients with schizophrenia].

Objective: To explore the role of peripheral serum complement protein in the pathogenesis of cognitive impairment by analyzing the correlation between peripheral serum levels of complement protein and cognitive function in first-episode drug-naive patients with schizophrenia. Methods: A total of 66 first-episode drug-naive schizophrenics (schizophrenia group) from the Third Affiliated Hospital of Sun Yat-sen University and 88 healthy volunteers (control group) were enrolled. Peripheral serum levels of complements (C3, C4 and CH50) were separately examined by liposome immunoassay and turbidimetric inhibition immunoassay. The MATRICS Consensus Cognitive Battery (MCCB) was used to assess the cognitive function. Results: Peripheral serum levels of C4, but not C3 and CH50, were significantly lower in patients with schizophrenia [0.20(0.16, 0.25) g/L] than those in the control group [0.23 (0.19, 0.27) g/L] (P<0.05). Moreover the peripheral serum levels of C3, C4 and CH50 were positively correlated with MCCB verbal fluency (r=0.258, r=0.283 and r=0.330, all P<0.05), and the peripheral serum levels of CH50 were negatively correlated with attention and alertness (r=-0.257, P<0.05). Conclusion: The decrease of peripheral serum complement C4 protein levels may be involved in the mechamism of cognitive impairment in schizophrenia.目的： 分析首发未用药精神分裂症患者外周血补体水平与认知功能之间的关系，探讨外周血补体因子在患者认知损伤发生机制中可能的作用。 方法： 纳入2017年9月到2020年1月在中山大学附属第三医院精神科就诊的首发未用药的精神分裂症患者66例（精神分裂症组），及通过广告招募的同期健康对照者88名（健康对照组）。采用免疫投射比浊法检测所有研究对象的外周血补体C3、C4浓度，采用脂质体免疫法测定CH50浓度；使用MATRICS共识认知成套测验（MCCB）评定所有研究对象的认知功能。比较精神分裂症组与健康对照组外周血补体因子浓度差异，并分析其与患者认知功能的关系。 结果： 精神分裂症组外周血补体C4水平[0.20（0.16，0.25）g/L]低于健康对照组[0.23（0.19，0.27）g/L]（均P<0.05），C3、CH50水平两组差异无统计学意义（P>0.05）。与健康对照组相比，精神分裂症组10项认知测验得分均显著下降（P<0.001）。精神分裂症组外周血补体C3水平与言语流畅性呈正相关（r=0.258，P<0.05），外周血补体C4水平与言语流畅性呈正相关（r=0.283，P<0.05），外周血CH50水平与言语流畅性呈正相关（r=0.330，P<0.01）、与注意性/警觉性呈负相关（r=-0.257，P<0.05）。 结论： 首发未用药精神分裂症患者外周血补体C4水平降低，与精神分裂症认知功能损害存在一定的相关性。.