“These results provide a strong impetus for all organizations with individuals who perform intense exercise to develop formalized protocols for universal precautions,” said Dr. Rakhi Naik. She is an assistant professor of medicine in the hematology division at Johns Hopkins University in Baltimore.
Thompson added that the evidence in this paper “underscores the benefit that these measures can have for all individuals, not just those with sickle cell trait.”
Sickle cell trait rarely causes symptoms of sickle cell disease, says the U.S. Centers for Disease Control and Prevention. The concern with sickle cell trait is muscle breakdown due to intense exercise, often in extreme temperatures.
Although uncommon, exertional rhabdomyolysis can be fatal, Kurina said. That’s why the research team focused on that outcome.
While there was no significant difference in death risk, researchers did find that black soldiers with sickle cell trait were 54 percent more likely than their counterparts without the trait to suffer exertional rhabdomyolysis.
That level of risk is on par with the higher risks associated with tobacco use and obesity, the researchers found.
The absolute risk was quite small. Just over 1 percent of black soldiers with sickle cell trait in the study developed exertional rhabdomyolysis, compared to 0.8 percent of their counterparts without sickle cell trait, Kurina said.
For the new analysis, researchers had access to medical and administrative data on all active duty soldiers in the United States.
The researchers identified 391 exertional rhabdomyolysis events during the study period. Risk rose with age, but was much lower for women than for men.
Only one death was observed among soldiers with exertional rhabdomyolysis, and it involved a soldier without sickle cell trait, the study authors noted.
The study, published Aug. 3 in The New England Journal of Medicine, was funded by the U.S. National Heart, Lung, and Blood Institute in collaboration with the Uniformed Services University of the Health Sciences.