Correlation between ABO Blood Group Phenotype and the Risk of COVID-19 Infection and Severity of Disease in a Saudi Arabian Cohort

Abstract

Background Disease severity among patients infected with SARS-CoV-2 varies remarkably. Preliminary studies reported that the ABO blood group system confers differential viral susceptibility and disease severity caused by SARS-CoV-2. Thus, differences in ABO blood group phenotypes may partly explain the observed heterogeneity in COVID-19 severity patterns, and could help identify individuals at increased risk. Herein, we explored the association between ABO blood group phenotypes and COVID-19 susceptibility and severity in a Saudi Arabian cohort. Methods In this retrospective cohort study, we performed ABO typing on a total of 373 Saudi patients infected with SARS-CoV-2 and conducted association analysis between ABO blood group phenotype and COVID-19 infection severity. We then performed gender-stratified analysis by dividing the participating patients into two groups by gender, and classified them according to age. Results The frequencies of blood group phenotypes A, B, AB and O were 27.3, 23.6, 5.4 and 43.7%, respectively. We found that blood group phenotype O was associated with a lower risk of testing positive for COVID-19 infection (OR 0.76 95% CI 0.62–0.95, p = 0.0113), while blood group phenotype B was associated with higher odds of testing positive (OR 1.51 95% CI 1.17–1.93, p = 0.0009). However, blood group phenotype B was associated with increased risk in the mild and moderate group but not the severe COVID-19 infection group. Blood group phenotype O was protective in all severity groups. Conclusion Our findings provide evidence that blood group phenotype B is a risk for COVID-19 disease while blood group phenotype O is protective from COVID-19 infection. However, further studies are necessary to validate these associations in a larger sample size and among individuals of different ethnic groups.

ABO blood group and link to COVID-19: A comprehensive review of the reported associations and their possible underlying mechanisms

“…While several studies failed to reproduce significant associations between ABO blood-type and SARS-CoV-2 infection [ 20 , 60 , [65] , [66] , [67] ], others reached significant associations for blood types other than A and O. Blood type B was related to significantly higher risk of SARS-CoV-2 infection in some studies [ 59 , [68] , [69] , [70] , [71] , [72] , [73] ]; and a meta-analysis indicated that blood type B is associated with higher risk of SARS-CoV-2 infection in Asian, but not in European cohorts [ 74 ]. AB blood type, in turn, has been significantly related to either higher [ 47 , 62 , 68 , [70] , [71] , [72] , [73] , 75 ] or lower [ 59 , 61 ] risk of acquiring COVID-19.…”

“…Blood type B was related to significantly higher risk of SARS-CoV-2 infection in some studies [ 59 , [68] , [69] , [70] , [71] , [72] , [73] ]; and a meta-analysis indicated that blood type B is associated with higher risk of SARS-CoV-2 infection in Asian, but not in European cohorts [ 74 ]. AB blood type, in turn, has been significantly related to either higher [ 47 , 62 , 68 , [70] , [71] , [72] , [73] , 75 ] or lower [ 59 , 61 ] risk of acquiring COVID-19.…”

“…As can be seen from Table 2 , results regarding severity and outcomes are more variable than those regarding the risk of infection. Several studies that reported associations between ABO blood type and the risk of SARS-CoV-2 infection failed to describe any association for severity [ 47 , 49 , 54 , 56 , 57 , 59 , 61 , 68 , 71 , 73 , 78 ] or reached distinct associations [ 51 , 70 ]. Other studies also reported no association between ABO blood types and severe COVID-19 outcomes but in accordance with the finds reported for the risk of infection [ 19 , 20 , 60 , 65 , 67 ].…”

“…For instance, the frequency of the B phenotype is increased in Asia at the expense of both A and O phenotypes, which, together, are largely predominant in Western Europe, with the Middle East displaying an intermediary distribution [ 25 ]. Such difference could explain the association between blood type B and the increased risk of SARS-CoV-2 infection reported by some Indian or Middle Eastern studies [ 59 , 69 , 71 , 73 ]. Likewise, the lack of association between ABO blood type and the risk of SARS-CoV-2 infection [ 19 , 63 ] or a significant positive association with blood type O [ 64 ] in U.S multiethnic cohorts before adjusting for ethnicity can be explained by the fact that ethnic groups among who blood type O is predominant, like Hispanics and black non-Hispanics, have been disproportionally affected by the COVID-19 pandemic in the U.S [ 19 , 64 ].…”

Carbohydrate Ligands for COVID-19 Spike Proteins

“…The relationships between ABO blood group antigens and COVID-19 have also been investigated by many researchers. Jawdat et al found that blood group B is a risk factor for COVID-19 and blood group O is protective factor for COVID-19 infection [53]. Zhao et al analyzed the ABO blood group distribution among 2173 COVID-19 patients.…”