In the summer of 2005, Curtis Lofton was an incoming senior at Kingfisher High School in central Oklahoma and a star linebacker on the Yellowjackets offensive line. That July he was participating in a 7-on-7, a series of non-tackle skirmishes played one after the other. Four games into the tournament, his calves started cramping. He figured he wasn’t drinking enough Gator-ade. During the fifth game, the radiating pain in his lower legs reached his quads. Soon after, muscles throughout his body seized up. He was whisked to the hospital and given five bags of fluid until the anguish stopped.
After graduation from Kingfisher, Lofton’s skill on the football field and in the classroom earned him a scholarship to the University of Oklahoma. The school was at the forefront of testing players for the genetic variant responsible for sickle cell disease, one of a group of hemoglobin disorders that causes oxygen-ferrying red blood cells — which are normally flexible and Frisbee-shaped — to “sickle” into rigid, sticky crescents that block blood flow. Two copies of the variant can lead to lifelong complications such as anemia, pain, and premature death. Sickle cell disease affects all races, but in the U.S., it occurs most frequently in African-Americans.
A person with sickle cell trait — born with one abnormal version of the HBB gene and one normal copy of it — is usually symptom-free. For a long time, however, doctors have been concerned that under extreme heat or exertion, or at high altitudes, a person who carries sickle cell trait might be in heightened danger of a condition called rhabdomyolysis. This occurs when blood cells sickle under low oxygen or dehydration, and the circulation logjam causes muscles to deteriorate. In rare cases, it can lead to kidney failure and death.
When Lofton arrived at the University of Oklahoma (OU), Randy Eichner was the internist on staff. Eichner has long been concerned that undetected sickle cell trait poses a threat to athletes. At his urging, the Sooners began screening all players for the trait. To Lofton’s surprise, he tested positive. “It was kind of a revelation for me,” he says. Although he had spent many a postgame bus ride in unexplained pain, and been in and out of hospitals seeking answers, sickle cell trait was never considered, he says. “They ran all kinds of tests, and nobody could figure out what was causing it.” He credits Eichner and OU with saving his life.
Other athletes have not been so fortunate. In 2006, a football player with sickle trait at Rice University in Houston died following a strenuous workout. His parents sued the school for wrongful death.
In settling the litigation, the National Collegiate Athletic Association (NCAA) began screening Division I athletes who hadn’t been previously tested for sickle cell trait in 2010. The policy has since been widened to cover Division II and III athletes.
The story would have ended here, had objections to the policy not come from some surprising camps, including the Sickle Cell Disease Association of America and the American Society of Hematology.
Today, even after seven years of screening, those organizations remain skeptical. Some worry that a policy instituted at the recommendation of lawyers, not doctors, lacks sufficient medical oversight and attention to counseling. A spokesman for the NCAA said no one was available to discuss how procedures are being standardized, but in an email, the spokesman said that the testing procedures fell to each member school. For their part, schools often feel they have been left to navigate the testing and counseling question on their own.
“This was done in the context of a legal settlement,” says Lakshmanan Krishnamurti, a pediatrics professor at Emory University and the director of the Blood Disorders Center at Children’s Healthcare of Atlanta. “It was implemented without consultation or involvement of the public and disproportionately affects people who are socioeconomically disadvantaged.”
Opponents have cited other concerns. Among them are unclear safeguards for informed consent; cost (See “Not All Tests Are Created Equal,” page 30); and the possibility that those who test positive will suffer from stigmatization and discrimination.
“Part of our concern is that the traditional way of doing informed genetic counseling may not be done [in sickle cell trait testing of athletes],” says Biree Andemariam, a hematologist from the New England Sickle Cell Institute and the chief medical officer of the Sickle Cell Disease Association of America. “There should be informed consent for testing, as well as pre- and post-test counseling about what the results might mean for the athlete’s future professional athletic career and reproductive planning.”
This was done in the context of a legal settlement. It was implemented without consultation or involvement of the public and disproportionately affects people who are socioeconomically disadvantaged .
Andemariam’s organization advocates “universal precautions” during training, in which players are conditioned and protected by such measures as acclimatizing to heat, ensuring proper hydration, and closely monitoring for signs of overtraining. Such precautions benefit all athletes, of course; rhabdomyolysis during heat stress is a risk even to those who do not have sickle cell trait. In January, three football players from the University of Oregon were admitted to the hospital with rhabdomyolysis following intense conditioning workouts.
“The specific reason given for screening is to prevent exercise-related deaths,” says Nigel Key, director of the Hemophilia and Thrombosis Center at the University of North Carolina in Chapel Hill. But in a review in the British Journal of Hematology in 2015, he made a case for universal precautions; he says if they are being followed, then genetic screening isn’t necessary.
One of the largest tests of universal precautions was published in August 2016 in the New England Journal of Medicine. Researchers from the U.S. Army, which does not screen for sickle cell trait, studied a population of almost 48,000 soldiers, of whom 3,564 had sickle cell trait in their medical record. Between 2011 and 2014, 391 cases of rhabdomyolysis occurred. The authors found that having sickle cell trait was in fact associated with about a 50 percent greater chance of developing rhabdomyolysis.
But in the Army study, having sickle cell trait did not increase the chance of dying; in fact, the one fatality occurred in a soldier who did not have the trait. And other factors, such as the use of cholesterol-lowering statin drugs, were much more of a threat than sickle cell trait. “It’s wrong to say there is a greatly increased risk, but also wrong to say there is no risk,” says Key. “The critical thing is that universal precautions are effective.”
Nonetheless, opinions still differ on whether training safeguards alone are enough to protect players, given that there is much about sickle cell trait that doctors are still trying to understand, says Morey Blinder, a hematologist at Washington University School of Medicine in St. Louis. In his view, the unknowns about sickle cell trait make testing more important, not less. “Until we understand sickle cell a little better, I would still feel most comfortable if we knew someone’s [genetic] status beforehand,” he says. “Maybe these exertional collapses are the tip of the iceberg. Maybe there are other milder symptoms that go with sickle trait.”
And perhaps the conversation doesn’t need to be about screening or no screening, but how to ensure that screening is scientific, ethical, and reliable, says Emory’s Krishnamurti. “The intention was to detect sickle cell trait, but people implemented screening without a plan [for] what to do with the information.” Before he came to Atlanta, Krishnamurti practiced at the University of Pittsburgh when testing of athletes began. Although hematologists as a whole were not in favor, he says, “I took a different tack in Pittsburgh. I said, ‘Okay this is happening anyway. So can this be done properly?’ I used my own grant funding to do the right test. I provided genetic counseling. I educated the athletes and the coaches.”
That kind of education may be what’s needed most, says Ryan Clark, a sickle cell trait carrier who retired from a pro football career in 2015 and now serves as a commentator for ESPN. In 2007, while playing with the Pittsburgh Steelers in a game in Denver, his blood started to sickle. He was rushed to the hospital and ended up losing his spleen. Other than that high-altitude episode, “I played 13 years and never had any problems whatsoever,” he says. “I out-trained everybody I knew.”
If coaches and other staff aren’t given the proper knowledge, Clark fears that some players may be unnecessarily labeled. “I don’t want people with the trait to be looked at as defective,” he says, and notes its effects on health risk are still being debated. “If we begin to attribute other things to the trait that we don’t have findings for, I think these kids will start to be discriminated against. If they are good enough players, it won’t matter. But will recruiters want to bet on marginal players?”
How the policy plays out in individual schools is hard to know. “We have no national data yet,” says Charmaine Royal, an associate professor of African & African American Studies and Biology at Duke University. She and her colleagues recently completed a study of Division I schools across North Carolina, which she says is the largest data set gathered so far on the actual implementation of the policy. “When we talk to athletic staff, including athletic trainers and coaches, one of the common themes we hear is confusion about implementation of the policy. ”
When Royal surveyed North Carolina schools, she found variation in tests being used, procedures, and levels of informed consent. Some athletes didn’t even know they were being screened. The good news, she says, is that there was no evidence that testing had caused any harm, and players were generally comfortable with the program. She has applied for a grant to gauge the procedures and effects of screening on a national scale.
Randy Eichner, now retired from OU, says that the policy has saved lives. He cites 10 deaths among Division I athletes that occurred between 2000 and 2010, but only one or two since the policy began. One death occurred in August 2016, when 20-year-old Eric Goll, a football player from Chadron State College in Nebraska, died after collapsing at practice. Goll transferred from Florida A&M, where he tested positive for sickle cell trait, but when he transferred to Chadron State his records did not come with him.
Curtis Lofton believes one of the lives saved was his. Revealing his sickle cell trait status did not hurt his career. He graduated from OU and went on to the pros, playing for teams in Atlanta, New Orleans, and Oakland, California. “There are a ton of athletes in the NFL who have sickle trait,” he says. “They know what they have, and they know their limits.”
When players and coaches know they are at risk, he says, they are mindful of how hard to push themselves. Whenever Lofton feels his muscles tighten during practice, he knows to sit out and drink water until the symptoms subside. Since he finished high school, he has only been to the hospital once. And he was happy to be there: it was for the arrival of his daughter, born healthy and free of the trait.