Association of Sociodemographic Factors and Blood Group Type With Risk of COVID-19 in a US Population
Jeffrey L. Anderson, Heidi T. May, Stacey Knight, Tami L. Bair, Joseph B. Muhlestein, Kirk U. Knowlton, Benjamin D. Horne
Abstract
suggested that blood group A was associated with increased susceptibility and blood group O was associated with reduced susceptibility to SARS-CoV-2 infection. These reports motivated widespread interest in examining ABO blood groups as potential COVID-19 risk factors. Subsequent studies from Italy and Spain 2 reported that blood group A was associated with an increased risk of severe COVID-19 and blood group O was associated with a reduced risk. In contrast, a large Danish study 3 implicated disease susceptibility but not severity. However, observations from Boston, Massachussets, 4 and New York, New York, 5 did not confirm any specific associations between ABO blood group and disease. The controversy raised by these contrasting reports led to this casecontrol study.