ABO in Correlation to the Requirement of Mechanical Ventilation and Mortality in Critically Ill Patients With COVID-19

Background: Coronavirus disease 2019 (COVID-19) is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) that was first discovered in December 2019 and turned to be pandemic in early March 2020. We aimed to describe the dominant ABO group and outcomes of critically ill patients (respiratory failure requiring mechanical ventilation and mortality) in a Saudi Arabian setting. Methods: We conducted an observational, analytic cross-sectional, retrospective study in a tertiary care hospital. Around 90 candidates tested positive for COVID-19 were enrolled in this study during admission to critical care unit between May 2020 and September 2020. Blood group was detected in all patients included in the study during admission to critical care unit. Results: In this study, data of 90 patients with COVID-19 admitted to critical care unit were collected. Some prevalent medical conditions were collected, in which hypertension (64.2%) and diabetes mellitus (58.9%) were the most reported comorbidities among patients and there was no significant difference between groups. Most of the sample had blood group of O (45.6%), while the least group was AB (5.6%). Patients with blood group of A/AB showed the highest mortality vs. group O/B (32% vs. 18.5%) with significant P value of 0.001. Patients of groups A/AB had higher risk for intubation than O/B groups (52.0% and 49.2%, respectively; confidence interval of 0.44 - 2.8 with insignificant P value of 0.055). Length of stay in critical care unit was significantly higher in group A/AB with a mean course of 18.20 days in comparison to group O/B with a mean course of 12.63 days (P = 0.033). Conclusion: Our data indicate that critically ill patients with COVID-19 with blood group A/AB are at increased risk of mortality and length of stay in critical care unit, with insignificant requirement of mechanical ventilation when compared with patients with blood group O/B. Future larger studies are needed to validate and understand the underlying mechanisms.