The Grapevine

Your Blood Type Could Determine Whether You Survive A Serious Injury

Can your blood type play a role in influencing your chances of survival after a severe injury? A new study based on emergency care patients in Japan may have the answers, and it appears to be bad news for people with blood type O.

The study titled “The impact of blood type O on mortality of severe trauma patients” was published in the journal Critical Care on May 1. 

“Recent studies suggest that blood type O could be a potential risk factor for hemorrhage,” said lead author Dr. Wataru Takayama.

Hemorrhage refers to severe and uncontrollable bleeding from ruptured vessels.

“Loss of blood is the leading cause of death in patients with severe trauma but studies on the association between different blood types and the risk of trauma death have been scarce. We wanted to test the hypothesis that trauma survival is affected by differences in blood types,” he said.

The research team obtained data from the medical records of 901 patients who had experienced severe trauma, which is a serious injury that might cause disability or death. From 2013 to 2016, all the patients were transported to one of two tertiary emergency critical care medical centers in Japan — Tokyo Medical and Dental University Hospital of Medicine or Matsudo City Hospital.

The analysis revealed a death rate of 28 percent among patients with blood type O, almost three times higher than the rate observed with other blood types. The combined death rate of patients with type A, type B, and type AB was 11 percent.

When you experience severe trauma, your body undergoes a process called hemostasis, which is the first stage of wound healing. Von Willebrand factor (VWF), a blood glycoprotein, plays a significant role by binding to cells and proteins during the formation of a blood clot, and these protect the body from losing more blood.

The researchers cited past studies suggesting the blood type O contains lower levels of VWF, which may explain the higher death rate in trauma patients of the group.

“Our results also raise questions about how emergency transfusion of O type red blood cells to a severe trauma patient could affect homeostasis, the process which causes bleeding to stop, and if this is different from other blood types,” Dr. Takayama added. “Further research is necessary to investigate the results of our study and develop the best treatment strategy for severe trauma patients.”

The researchers highlighted limits of the study such as the use of only Japanese patients' data, which may need to be confirmed with other ethnic groups. Since the study strictly compared type O blood and non-type O blood, the researchers did not examine types A, B, and AB in terms of individual impact. 

In the United States, type O-positive has been shown to be the most common blood group followed by type A-positive, while AB-negative was found to be the rarest.