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Statement on Screening for Sickle Cell Trait and Athletic Participation


The American Society of Hematology (ASH) represents approximately 16,000 physicians, scientists, and medical trainees committed to the study and treatment of blood and blood-related diseases. ASH members include clinicians who specialize in treating children and adults with sickle cell disease (SCD) and researchers who investigate the causes and potential treatments of SCD manifestations.

Sickle cell disease is an inherited blood disorder that affects 80-100,000 Americans, mostly but not exclusively of African ancestry. SCD causes production of abnormal hemoglobin, resulting in severe anemia, pain, other devastating disabilities, and, in some cases, premature death. SCD requires the inheritance of two defective globin genes. Eight to 10 percent of African Americans have sickle cell trait. Individuals with sickle cell trait do not have SCD, but are carriers of one defective gene associated with SCD. The majority of their hemoglobin is normal. Millions of Americans and hundreds of millions of individuals worldwide with the sickle cell trait enjoy normal life spans without serious health consequences. Rarely, clinical issues such as exertional rhabdomyolysis (the rapid breakdown of skeletal muscle due to injury to muscle tissue) have been reported in individuals with sickle cell trait. These incidents have generally occurred under extreme conditions such as severe dehydration and high intensity physical activity.

In April 2010, the National Collegiate Athletic Association (NCAA) adopted a policy requiring Division I institutions to perform sickle cell trait testing for all incoming student athletes. This requirement arose from a lawsuit following the death during preseason training of a college football player, who was subsequently found to have sickle cell trait. The policy includes an opt-out provision for students who can provide results from a prior test and for those who are willing to sign a waiver of liability against the university and the NCAA. There have been no well-controlled, hypothesis-driven prospective studies on sickle cell trait and exertional collapse. Most cases reported to date are autopsy descriptions or case reports in which other potential contributors are not fully investigated.The extremely small number of deaths in a highly prevalent carrier state implies that other genetic or environmental factors play a role. Rhabdomyolysis and exertional collapse also occur in individuals without sickle cell trait.

Universal preventive measures implemented by the U.S. Army to mitigate risk of exertion-related heat illness for all soldiers include heat acclimatization, monitoring work-rest cycles, guidelines for nutrition and hydration, and maintaining staff preparedness for early and rapid detection and treatment of heat illnesses. Using these universal guidelines, the death rate has been significantly lowered for all individuals undergoing training, including those with sickle cell trait. Similarly, governmental authorities in Brazil (which has similar sickle cell carrier rates as the U.S.) have promulgated guidelines to avoid heat-related injuries and see no need for athletes or military personnel to be screened for sickle cell trait.

ASH Policy

ASH does not support testing or disclosure of sickle cell trait status as a prerequisite for participation in athletic activities. ASH believes that current scientific evidence does not justify this requirement. It is also not consistent with good medical practice or established principles of public health ethics. Screening for sickle cell trait should be voluntary and should take place in a setting that ensures privacy and is performed by a knowledgeable provider who is able to offer comprehensive counseling.

ASH recommends the implementation of universal interventions to reduce exertion-related injuries and deaths, since this approach can be effective for all athletes irrespective of their sickle cell status. Universal interventions are used successfully by organizations like the U.S. Army and the Brazilian military. Until the NCAA requires universal interventions, student athletes remain at risk for suffering from significant heat stress/exertion-related injury or death. Participation in athletics can be made safer with these measures, thereby rendering screening for and disclosure of sickle cell trait status unnecessary.

ASH believes that the NCAA Division I policy, as currently written and implemented, has the potential to harm the student athlete and the larger community of individuals with sickle cell trait. The NCAA policy attributes risk imprecisely, obscures consideration of other relevant risk factors, fails to incorporate appropriate counseling, and could lead to stigmatization and racial discrimination.

ASH strongly supports increased biomedical and population-based research on sickle cell trait as it relates to exertion-related illness, as well as other clinical conditions. New knowledge derived from research should benefit individuals with sickle cell trait and help inform public policy.

Frequently Asked Questions for Medical Experts and Patients

Access a list of frequently asked questions about sickle cell trait for medical experts and patients

Organizations Supporting ASH's Statement on Screening for Sickle Cell Trait and Athletic Participation

The American Society of Hematology is the world’s largest professional society concerned with the causes and treatment of blood disorders. Its mission is to further the understanding, diagnosis, treatment, and prevention of disorders affecting blood, bone marrow, and the immunologic, hemostatic, and vascular systems by promoting research, clinical care, education, training, and advocacy in hematology. The official journal of ASH is Blood, the most cited peer-reviewed publication in the field, which is available weekly in print and online.