Effectiveness of convalescent plasma in Indian patients with COVID-19.

Background: Convalescent plasma (CP) is being used as a treatment option in hospitalized patients with COVID-19. Till date, there is conflicting evidence on efficacy of CP in reducing COVID-19 related mortality.

Objective: To evaluate the effect of CP on 28-day mortality reduction in patients with COVID-19.

Methods: We did a multi-centre, retrospective case control observational study from 1st May 2020 to 31st August 2020. A total of 1079 adult patients with moderate and severe COVID-19 requiring oxygen, were reviewed. Of these, 694 patients were admitted to ICU. Out of these, 333 were given CP along with best supportive care and remaining 361 received best supportive care only.

Results: In the overall group of 1079 patients, mortality in plasma vs no plasma group was statistically not significant (22.4% vs 18.5%; p = 0.125; OR = 1.27, 95% CI: 0.94--1.72). However, in patients with COVID-19 admitted to ICU, mortality was significantly lower in plasma group (25.5% vs 33.2%; p = 0.026; OR = 0.69, 95%CI: 0.50-0.96). This benefit of reduced mortality was most seen in age group 60 to 74 years (26.7% vs 43.0%; p = 0.004; OR = 0.48, 95% CI: 0.29-0.80), driven mostly by females of this age group (23.1% vs 53.5%; p = 0.013; OR = 0.26, 95% CI: 0.09-0.78). Significant difference in mortality was observed in patients with one comorbidity (22.3% vs 36.5%; p = 0.004; OR = 0.50, 95% CI: 0.31-0.80). Moreover, patients on ventilator had significantly lower mortality in the plasma arm (37.2% vs 49.3%; p = 0.009; OR = 0.61, 95% CI: 0.42-0.89); particularly so for patients on invasive mechanical ventilation (63.9% vs 82.9%; p = 0.014; OR = 0.37, 95% CI: 0.16-0.83).

Conclusion: The use of CP was associated with reduced mortality in COVID-19 elderly patients admitted in ICU, above 60 years of age, particularly females, those with comorbidities and especially those who required some form of ventilation.