Association Between Peripheral Inflammatory Markers And Postoperative Cognitive Dysfunction:A Meta-Analysis

BackgroundPostoperative cognitive dysfunction(POCD)is common following cardiac and non-cardiac surgery,but the pathogenic mechanisms remain unknown.Many studies suggest that an inflammatory response is a key contributor to POCDMethodsAn online search was performed to identify peer-reviewed studies without language restriction that measured peripheral inflammatory markers of patients with and without POCD,using PubMed?the Cochrane library?EMBASE?ISI Web of Knowledge?Google scholar?Baidu scholar?CNKI?Weipu and Wanfang.Extracted data were analyzed with Review Manager(version 5.1),STATA(versionl2.0).The standardized mean difference(SMD)and the 95%confidence interval(95%CI)were calculated for each outcome using a random effect model.Tests of heterogeneity assessment of bias,and meta-regression were performed in the meta-analysisResultsA total of 15 studies that measured the concentrations of peripheral inflammatory markers were included.The current meta-analysis found significantly higher concentrations of S-100?(SMD[95%CI])(1.82[0.9,2.74],p<0.001,N[POCD/non-POCD]=195/431,8 studies),and interleukin(IL)-6(SMD[95%CI])(1.35[0.67,2.02],p<0.001,N[POCD/non-POCD]=128/162,6 studies),but not of neuron specific enolase,interleukin-1?,or tumor necrosis factor-a,in POCD compared with patients without POCD.In meta-regression analyses,we didn't find a significant positive association between the SMD and the preoperative interleukin-6 or S-100?peripheral blood concentration in patients with POCDConclusionsThis study shows that POCD is indeed correlated with the concentrations of peripheral inflammatory markers,particularly interleukin-6 and S-100?,but the preoperative concentration of interleukin-6 and S-100? cannot be used as a predictor of POCD.