Role of peripheral inflammatory markers in postoperative cognitive dysfunction (POCD): a meta-analysis

PLoS One. 2013 Nov 13;8(11):e79624. doi: 10.1371/journal.pone.0079624. eCollection 2013.

Abstract

Background: Postoperative 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 POCD. The current meta-analysis shows that the levels of peripheral inflammatory markers are associated with POCD.

Methods: An 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, ScienceDirect, SinoMed and the National Knowledge Infrastructure database. Extracted data were analyzed with STATA (version 12).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-analysis.

Results: A total of 13 studies that measured the concentrations of peripheral inflammatory markers were included. The current meta-analysis found significantly higher concentrations of S-100β(SMD[95%CI]) (1.377 [0.423, 2.331], p-value < 0.001, N [POCD/non-POCD] =178/391, 7 studies), and interleukin(IL)-6 (SMD[95%CI]) (1.614 [0.603,2.624], p-value < 0.001, N[POCD/non-POCD] = 91/99, 5 studies), but not of neuron specific enolase, interleukin-1β, or tumor necrosis factor-α , in POCD compared with patients without POCD. In meta-regression analyses, a significant positive association was found between the SMD and the preoperative interleukin-6 peripheral blood concentration in patients with POCD (Coef.= 0.0587, p-value=0.038, 5 studies).

Conclusions: This study shows that POCD is indeed correlated with the concentrations of peripheral inflammatory markers, particularly interleukin-6 and S-100β.

Publication types

  • Meta-Analysis
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Biomarkers / blood
  • Cognition Disorders / blood*
  • Cytokines / blood
  • Humans
  • Inflammation Mediators / blood*
  • Interleukin-6 / blood
  • Postoperative Complications / blood*
  • Publication Bias
  • S100 Calcium Binding Protein beta Subunit / blood

Substances

  • Biomarkers
  • Cytokines
  • Inflammation Mediators
  • Interleukin-6
  • S100 Calcium Binding Protein beta Subunit

Grant support

This work is supported by the National Natural Science Foundation of China (Grant No. 30871306). The funders had no role in the study design, data collection and analysis, decision to publish, or preparation of the manuscript.