Effect of convalescent blood products for patients with severe acute respiratory infections of viral etiology: a systematic review and meta-analysis

Int J Infect Dis. 2020 Sep 28;S1201-9712(20)32159-7. doi: 10.1016/j.ijid.2020.09.1443. Online ahead of print.

Abstract

Objectives: To determine whether convalescent blood products (CBPs) could offer a survival advantage for patients with severe acute respiratory infections (SARI) of viral etiology.

Design or methods: Up-to-date trials were identified by the authors through searches of Medline, Embase, Cochrane Library, Web of Science, ClinicalTrial.gov, and medRxiv from inception up to 14 September 2020. Meta-analysis was performed by using random-effects model.

Results: According to observational studies, the cases received CPBs showed a decline of all-cause mortality compared with cases without using (OR 0.36, 95% CI 0.23 to 0.56, P < 0.00001). The all-cause mortality in the randomized controlled trials (RCTs) showed no difference between the interventional group and the control group (OR 0.82; 95% CI 0.57 to 1.19; P = 0.30). Besides, CBPs did not increase the risk of adverse events between these two groups (OR 0.88; 95% CI 0.60-1.29; P = 0.51). Using CBPs earlier, compared with using CBPs later, was associated with a significant reduction in all-cause mortality (OR 0.18; 95% CI 0.08-0.40; P < 0.0001).

Conclusions: Based on the outcomes of RCTs, CBPs could not decrease all-cause mortality. Furthermore, comparing with later initiation of convalescent blood product therapy, earlier initiation of convalescent blood product therapy might decrease the rate of mortality.

Keywords: COVID-19; SARS-CoV-2; convalescent plasma; meta-analysis; meta-regression; mortality; severe acute respiratory infections of viral etiology.