Researchers at Utah’s Intermountain Healthcare have found that a person’s blood type likely does not contribute to their risk of contracting COVID-19 or of developing a severe infection, according to a study published last month in the Journal of the American Medical Association earlier this month.
The IHC researchers analyzed the outcomes of 107,796 people who tested positive for COVID-19 between March 3 and Nov. 3, 2020, and who had their blood type documented in their electronic health record.
“We had read a few mostly smaller early studies that indicated patients with type A blood fared worse with COVID-19 and those with type O fared better,” Dr. Jeffrey Anderson, lead study author and cardiologist at Intermountain Medical Center Heart Institute, said in a news release. “So, instead of studying a few hundred patients, we looked at more than 100,000 patients tested at Intermountain Healthcare facilities and found no relationship between a person’s blood type and their susceptibility to COVID-19 or whether they needed hospitalization or intensive care unit care.”
Similar to other findings, the study found men were more likely to test positive and had an increased risk for severe disease, as well as non-white patients and older patients.
“All of these demographic factors are consistent with what we’ve seen around the world, which gives us confidence in our database and these results for blood type,” Anderson said. “I think it’s important because it’s been, for us, really one of our primary objectives to identify patients who are at higher risk and to build risk scores.”
The results were somewhat of a surprise for researchers, especially since studies over the years have found connections between type A blood and risk for heart attack, Anderson said.
“We had gone into this study thinking we would probably validate or verify the reports of a relationship but we found none,” Anderson said.