There is no evidence to support the claim that physical exertion without muscle breakdown or heat injury causes sudden death in people with sickle cell trait (SCT), according to a systematic literature review published in
Blood. The review also found no high-level evidence that SCT causes acute pain crises.
In response to longstanding misconceptions about SCT and the risk of sudden death, the American Society of Hematology convened an expert panel of hematologists and forensic pathologists to systematically review existing research. The panel sought to answer whether individuals with SCT experience acute pain crises and whether physical exertion above baseline increases the risk of sudden death.
“This misconception has been especially prominent in cases involving Black men with SCT,” said ASH President Belinda Avalos, MD. “In light of the pervasive, widely publicized and harmful nature of this myth, the Society aims to further promote accurate information to protect and empower affected communities.”
The panel reviewed 1,474 citations and identified seven studies that reported original data, included laboratory testing for SCT in individuals and addressed the two primary research questions. Of these, none provided evidence that SCT leads to acute pain crises.
In one study of active-duty U.S. soldiers that examined mortality among those with SCT, investigators reported an increased risk of heat-related exertional rhabdomyolysis (muscle breakdown) in individuals with SCT but found no increased risk of mortality.
“In the absence of two medical conditions that we are all at risk for, exertional rhabdomyolysis or crush injuries leading to rhabdomyolysis, individuals with SCT are not susceptible to sudden death,” said Michael R. DeBaun, MD, MPH, a study author and professor at Vanderbilt University School of Medicine. “Even under these extreme environmental conditions, unexplained sudden death cannot be attributed to SCT.”
The review also included studies that cited the presence of sickled blood cells at autopsy as evidence of death by acute pain crisis in individuals with SCT. However, the expert panel found no human data to support this hypothesis, nor any clinical descriptions confirming an acute pain crisis immediately before death.
“Medicine, even in the post-mortem setting, is science,”
said corresponding author Lachelle D. Weeks, MD, PhD. “Our diagnoses have to make sense and be backed by medical evidence. Given the findings of this study, we owe it to individuals with SCT to ensure that post-mortem examinations check for evidence of rhabdomyolysis and other medical or traumatic causes of death.”
In response to these findings, ASH updated its
position statement on SCT, writing that “listing ‘sickle cell crisis’ or ‘sickle cell trait’ as a cause of death on an autopsy report for an individual with sickle cell trait is medically inaccurate and without medical evidence of causation.”
AABB encourages readers to review the whole statement on the
ASH website.
