Differences in COVID-19-related death rates between people of white and Asian ancestry may be partly explained by documented ethnic/racial differences in risk for blood clotting and pulmonary thrombotic events, investigators propose.
“Our novel findings demonstrate that COVID-19 is associated with a unique type of blood clotting disorder that is primarily focused within the lungs and which undoubtedly contributes to the high levels of mortality being seen in patients with COVID-19,” said James O’Donnell, MB, PhD, director of the Irish Centre for Vascular Biology at the Royal College of Surgeons in Ireland.
Dr. O’Donnell and colleagues studied pulmonary effects and outcomes of 83 patients admitted to St. James Hospital in Dublin, and found evidence to suggest that the diffuse, bilateral pulmonary inflammation seen in many patients with severe COVID-19 infections may be caused by a pulmonary-specific vasculopathy they label “pulmonary intravascular coagulopathy” (PIC), an entity distinct from disseminated intravascular coagulopathy (DIC).
“Given that thrombotic risk is significantly impacted by race, coupled with the accumulating evidence that coagulopathy is important in COVID-19 pathogenesis, our findings raise the intriguing possibility that pulmonary vasculopathy may contribute to the unexplained differences that are beginning to emerge highlighting racial susceptibility to COVID-19 mortality,” they wrote in a study published online in the British Journal of Haematology.
Study flaws harm conclusions
But critical care specialists who agreed to review and comment on the study for MDedge News said that it has significant flaws that affect the ability to interpret the findings and “undermine the conclusions reached by the authors.”
“The underlying premise of the study is that there are racial and ethnic differences in the development of venous thromboembolism that may explain the racial and ethnic differences in outcomes from COVID-19,” J. Daryl Thornton, MD, MPH, a fellow of the American Thoracic Society and associate professor of pulmonary, critical care, and sleep medicine at Case Western Reserve University, Cleveland, said in an interview. “This is an interesting hypothesis and one that could be easily tested in a well-designed study with sufficient representation from the relevant racial and ethnic groups. However, this study is neither well designed nor does it have sufficient racial and ethnic representation.”
Elliott R. Haut, MD, PhD, associate professor of surgery, anesthesiology and critical care medicine at Johns Hopkins Medicine, Baltimore, said in an interview that the study is “mediocre” and has the feel of a paper rushed to press.
“It talks about their theory that race, ethnicity, have an effect on venous thromboembolism, and that’s a pretty well-known fact. No one’s a hundred percent sure why that is, but certainly there are tons and tons of papers that show that there are groups that are at higher risk than others,” he said. “Their idea that this is caused by this pulmonary inflammation, that is totally a guess; there is no data in this paper to support that.”
Dr. Thornton and Dr. Haut both noted that the authors don’t define how race and ethnicity were determined and whether patients were asked to provide it, and although they mention the racial/ethnic breakdown once, subsequent references are to entire cohort are as “Caucasian.”
They also called into question the value of comparing laboratory data across continents in centers with different testing methods and parameters, especially in a time when the clinical picture changes so rapidly.