Meta-Analysis of D-Dimer, hsCRP and Cytokines in COVID-19 Severe/Critical Patients in China

Objective: To analyze the relationship between D-dimer, inflammatory markers, cytokines and disease severity, and the possibility of early identification of COVID-19 critical type patients. Methods: PubMed, EMBASE and CNKI databases were searched by computer, and references of related reviews and systematic reviews were manually searched as supplements. The retrieval deadline is February 9, 2021. According to the inclusion and exclusion criteria, the literatures were screened and the quality was evaluated, and then the data were extracted for meta-analysis. The fixed/random effects model was used to calculate the weighted mean difference (WMD) and 95% CI to evaluate whether the levels of D-dimer, hsCRP, IL-6, IL-8, IL-10 and TNF-α in critical type patients were statistically different from those in severe type patients. If there were statistical differences, logistic regression analysis was used, and establish the receiver operating characteristic curve (ROC) and area under the curve (AUC) of each index for the diagnosis of critical type patients. The best diagnostic value of COVID-19 critical type patients was calculated by Youden index. Results: A total of 3519 literatures entered the screening process. According to the inclusion and exclusion criteria, 40 articles were finally included in this study, and all of them were high-quality studies after evaluation. The results of meta-analysis showed that the levels of D-dimer, hsCRP, IL-6, IL-8 and IL-10 in critical type group were significantly higher than those in severe type group (P<0.05). Based on ROC curve, the AUC of D-dimer was 0.785 (95% CI: 0.671-0.899), AUC of hsCRP was 0.884 (95% CI: 0.632-1.000), AUC of IL-6 was 0.819 (95% CI: 0.700-0.939), which had diagnostic significance for critical type patients (P<0.05). The optimal diagnostic threshold of D-dimer was ≥2.00 mg/L (sensitivity 89.3%, specificity 64.0%); the optimal diagnostic threshold of hsCRP was ≥64.22 mg/L (sensitivity 75.0%, specificity 100%); the optimal diagnostic threshold of IL-6 was ≥33.01 ng/L (sensitivity 68.0%, specificity 92.0%). Conclusion: The levels of D-dimer, hsCRP, IL-6, IL-8 and IL-10 in COVID-19 critical type patients were significantly higher than those in severe type patients. Our results might be helpful in identify and risk reduction of mortality in critical types patients infected with COVID-19.