COVID‐19 and coagulation dysfunction in adults: A systematic review and meta‐analysis

The outbreak of 2019 novel coronavirus disease (COVID‐19) has posed a grave threat to the global public health. The COVID‐19‐induced infection is closely related to coagulation dysfunction in the affected patients. This paper attempts to conduct a meta‐analysis and systematically review the blood coagulation indicators in patients with severe COVID‐19. A meta‐analysis of eligible studies was performed to compare the blood coagulation indicators in patients with severe and nonsevere COVID‐19. PubMed, Embase, Web of Science, and the Cochrane Library were searched for studies published between 1 December 2019 and 7 May 2020. A total of 13 studies with 1341 adult patients were enrolled in this analysis. Platelet (weighted mean difference [WMD] = −24.83, 95% confidence interval [CI]: −34.12 to −15.54; P < .001), d‐dimer (WMD = 0.19, 95% CI: 0.09‐0.29; P < .001), and fibrinogen (WMD = 1.02, 95% CI: 0.50‐1.54; P < .001) were significantly associated with the severity in patients with COVID‐19. The meta‐analysis revealed that no correlation was evident between an increased severity risk of COVID‐19 and activated partial thromboplastin time (WMD = −1.56, 95% CI: −5.77 to 2.64; P = .468) or prothrombin time (WMD = 0.19, 95% CI: −0.13 to 0.51; P = .243). The single arm meta‐analysis showed that compared with the nonsevere group, the severe group had a lower pooled platelet (165.12 [95% CI: 157.38‐172.85] vs 190.09 [95% CI: 179.45‐200.74]), higher d‐dimer (0.49 [95% CI: 0.33‐0.64] vs 0.27 [95% CI: 0.20‐0.34]), and higher fibrinogen (4.34 [95% CI: 1.98‐6.70] vs 3.19 [95% CI: 1.13‐5.24]). Coagulation dysfunction is closely related to the severity of patients with COVID‐19, in which low platelet, high d‐dimer, and fibrinogen upon admission may serve as risk indicators for increased aggression of the disease. These findings are of great clinical value for timely and effective treatment of the COVID‐19 cases.