title: C-reactive protein as a predictor of mortality in critically ill patients: a meta-analysis and systematic review.
abstract: C-reactive protein is a marker of inflammatory response and has been widely investigated in cardiovascular and infectious diseases, especially to monitor therapeutic success. However, its role as a predictor of clinical outcome in critically ill patients remains uncertain and controversial. The objective of this study was to investigate the predictive value of C-reactive protein in critically ill patients. The databases of PubMed, the Cochrane clinical trial database and EMBASE (from inception to August 2010) were searched. Prospective non-randomised clinical studies comparing C-reactive protein concentrations between survivors and non-survivors were included. Pooled mean difference in C-reactive protein concentrations between survivors and non-survivors was calculated. Heterogeneity was analysed by I2. Sensitivity and subgroup analyses were conducted to explore the heterogeneity. Fourteen studies containing a total of 1969 patients were finally included in our analysis. The weighted mean difference in the C-reactive protein levels between survivors and non-survivors was 9.15 mg/l (95% confidence interval -6.50 to 24.81). The heterogeneity was large with I2 = 92%. Subsequent investigation of the heterogeneity with sensitivity analyses yielded no significant differences. The subgroup analysis showed that the weighted mean difference in early (within 48 hours) C-reactive protein levels between survivors and non-survivors was not significantly different, in contrast to the late (beyond 48 hours) C-reactive protein level. This was significantly greater in non-survivors with a weighted mean difference of 63.80 mg/l (95% confidence interval 35.67 to 91.93). Our systematic review shows that while the early C-reactive protein concentration is not a good predictor of survival in critically ill patients, the late C-reactive protein concentration may help to identify patients who are at risk of death.
authors.affiliation: Department of Critical Care Medicine, Jinhua Central Hospital, Zhejiang Province, China. zh_zhang1984@hotmail.com
authors.forename: Z
authors.initials: Z
authors.lastname: Zhang
authors.forename: H
authors.initials: H
authors.lastname: Ni
mesh_terms: D015415:Biomarkers / Q000032:analysis / Q000378:metabolism; D002097:C-Reactive Protein / Q000032:analysis* / Q000378:metabolism; D002986:Clinical Trials as Topic; D016638:Critical Illness; D006801:Humans; D011237:Predictive Value of Tests; D012680:Sensitivity and Specificity; D016019:Survival Analysis
chemical_list: D015415:Biomarkers; D002097:C-Reactive Protein