SARS CoV-19 Infection and ABO Blood groups, correlation with Laboratory Blood Parameter analysis and Mortality, a Single Centre Study in UK

Background and Aim There is controversial evidence available on the role of blood grouping in determining the susceptibility to SARS-CoV-19 infection. It is postulated that blood group anti-A antibodies offer some protection against SARS-CoV-19 infection and severity of illness due to anti- A antibodies blocking the binding of SARS-CoV-19 to respiratory epithelium. Hence people with blood group O may be protected against SARS-CoV-19 compared with blood group A and AB patients who may do worse. The aim of this study was to retrospectively analyse the ABO Rh blood group data on patients with SARS CoV-19 admitted in a single NHS center in UK hospital trust and further correlate the severity of infection and mortality with the type of blood group. Material and Methods We analysed data on 604 confirmed patients with SARS-CoV-19, who’s blood groups were known, from a single NHS centre in UK, admitted between February 2020 and March 2021. We correlated ABO Rh blood groups with mortality and various clinical, haematological and biochemical parameters. Patients were classified into four groups according to their blood group (blood group A, 197 patients: blood group B, 117 patients; blood group AB, 34 patients and blood group O, 256 patients). Results The analysis showed a tendency towards higher mortality in patients with blood group-A. Certain biochemical and inflammatory markers were lower in patients with blood group AB with a tendency to less organ dysfunction and morbidity. Comparison between deceased patients in all groups revealed significantly higher white blood cells (WBCs) (p=0.0308), neutrophil count (p=0.0073) in the A and B blood groups compared to the AB and O groups. However no statistically significant differences were found between the four groups in regard to neutrophil to lymphocyte ratio (NLR), neutrophil to eosinophil ratio (NER) and the white blood cells* neutrophil to eosinophil ratio (WBCS*Neut/Eos) which are known prognostic factors for SARS-CoV-19. Blood group Rh positive patients tended to have higher CRP and platelet count irrespective of primary blood group but no significant impact on mortality. Conclusion The study shows a tendency towards more inflammatory reaction in patients with blood group A and B and Rh positive groups but with no difference in mortality between the blood groups. We acknowledge that the small sample size limits the ability to draw conclusions for a wider population but it adds valuable information and insight in to effects of blood groups on clinical outcomes and inflammatory response to SARS-CoV-19 infection. A larger multicentre retrospective data collection and analysis would be useful with inclusion of patients admitted in intensive care.