High-Intensity Exercise and Renal Medullary Carcinoma in Those With Sickle Cell Trait
This publication was approved and written in close collaboration with Dr. Pavlos Msaouel.
Dr. Pavlos Msaouel is a clinician and cancer biologist who is focused on particularly rare forms of renal cell and urothelial carcinomas, including renal medullary carcinoma at The University of Texas MD Anderson Cancer Center. Dr. Msaouel is a featured expert in our health equity-focused Pro Hub that lists inclusive global healthcare professionals committed to advancing inclusive research and providing the highest quality care to all patients.
These articles are written by Diverse Health Hub to summarize complex medical research in order to facilitate deeper understanding. Diverse Health Hub publications are not intended to persuade its readers. We present information to create in-depth conversations that encourage patients to critically think and decide for themselves.
As the most commonly occurring blood disorder in the world, sickle cell trait primarily impacts those in the Black, Indigenous, and People of Color (BIPOC) community with African ancestry. We connected with Dr. Pavlos Msaouel about a study on high-intensity exercise in those with sickle cell trait. This is new research that has yet to be evaluated by other clinical researchers and should not be used to guide clinical practice.
What Is Renal Medullary Carcinoma (RMC) and Sickle Cell Trait (SCT)?
Renal medullary carcinoma (RMC) is a rare deadly type of cancer that predominantly afflicts young adults of African descent with sickle cell trait. Patients often start developing symptoms of blood in the urine and pain in the flanks on their sides where the kidneys are located, most often on the right side. The median survival rate for RMC is only 13 months despite the best available treatments. Sickle cell trait results when a person has one unaffected gene and one sickle cell gene. SCT has become more predominant in areas of Africa with high rates of malaria, since SCT provides a protective advantage against malaria in the blood. SCT is also more common in Latina and Latino people from Central America, the Caribbean, and South America; people of Southeast Asian descent; people of Mediterranean descent, and people of Middle Eastern descent.
What Is the High-Intensity Exercise Study on SCT Patients?
Renal medullary carcinoma (RMC) researchers are looking to learn more about a potential link between high-intensity exercise and low oxygen levels in the kidneys of those with sickle cell trait. It’s important to note there have been no verified links of light and moderate exercise levels to low oxygen levels in the kidneys. The focus is on high-intensity exercise only, and studies have shown no link between moderate-intensity exercise and oxygen levels in the kidneys. Exercise is an important part of maintaining a healthy body and is strongly encouraged, including for individuals with sickle cell trait.
What Are the Potential Risk Factors for SCT Progressing to RMC?
Among the information reviewed in the study, researchers compared a large group of RMC patients against a group of patients with other cancers of the reproductive and urinary systems.. After review, the profile for most RMC patients were determined to be men of African descent with the primary tumor in the right kidney. Further examination of the data showed that men of African descent who also were in the military, engaged in high-intensity exercise, and had high levels of skeletal muscle mass had a higher incidence of RMC in comparison to the non-RMC group.
Was Additional Research Data Found About SCT and RMC?
The researchers also wondered about a possible link between military service and RMC. When they compared the data of RMC patients who served in the U.S. military, they found a higher than expected percentage RMC patients have served in the military than expected compared to the similarly aged group of Black SCT patients in the U.S. The researchers also wanted to see how high-intensity exercise impacted the kidneys of mice with SCT. They found that the kidneys of mice with SCT to have disorganized blood vessels that also had shorter length and diameter of blood vessels compared to the kidneys of mice without SCT. High-intensity exercise led to lower oxygen levels in the kidneys of the mice with SCT, but moderate-intensity exercise actually improved the oxygen levels in the kidneys of mice.
What Is High-Intensity Exercise and What Is Moderate-Intensity Exercise?
The formal definition of moderate-intensity exercise is between 50 to 70 percent of your maximum heart rate. The maximum heart rate can be calculated by 220 minus your age. Thus, if you are 40 years old, then your maximum heart rate is 180 beats per minute.
When you perform moderate-intensity exercise your breathing may quicken but you are not out of breath. You may develop a light sweat after about 5 to 10 minutes of activity. You can carry on a conversation while exercising but cannot sing.
The formal definition of high-intensity exercise is between 80 percent or more of your maximum heart rate. When you perform high-intensity exercise your breathing may be deep and rapid, you may develop a sweat after just a few minutes of activity, and you cannot say more than a few words without pausing for a breath.
It should again be emphasized that exercise is NOT contraindicated for patients with sickle cell trait if it is performed under safe conditions. Universal precautions adopted by athletes and military recruits may prevent deaths and help athletes with sickle cell trait thrive in their sport.
These include staying well-hydrated throughout your exercise with frequent stops for drinking. Avoid high caffeine intake and other stimulants around the time of exercise. Avoid repeated high-intensity timed drills with limited recovery time in the first two weeks of new training session. Limit exercise when sick. Provide ample rest and recovery between repetitions especially during “sprints” and intense stations or drills. Make fluids readily available and schedule frequent breaks. The CDC provides further recommendations on exercise in individuals with sickle cell trait here.
How Can Renal Medullary Carcinoma Be Detected Early?
With RMC being a rare but serious cancer, there are steps that can be taken for early detection of RMC. If you have an ethnic background from Africa or have relatives with sickle cell trait, make sure to get screened for sickle cell trait. Also make sure to see a doctor immediately if you notice blood in your urine and seek out doctors who specialize in treatment of renal medullary carcinoma.
How Can SCT Patients Protect Themselves Against Heat Stroke, Muscle Breakdown, and Pain Crises?
Studies have shown that some athletes with SCT are more likely to experience muscle breakdown and heat stroke than those without SCT. For those involved with high-intensity competitive sports and military training, it’s important to take steps to prevent illness. Make sure to:
Avoid overheating and dehydration by drinking plenty of water before, during, and after exercise
Take frequent breaks for rest between rigorous exercise drills
Build intensity slowly and set your exercise pace
Maintain a cool body temperature in hot and humid environments by taking breaks to air-conditioned areas or by misting your body with water
Avoid exercise in high-altitude conditions or allow more travel time to allow your body to have gradual adjustment to high altitudes
Those with sickle cell trait can sometimes develop a complication of sickle cell disease (SCD) called pain crisis. To prevent pain crisis, make sure to:
Drink plenty of water to avoid dehydration
Avoid low-oxygen situations of intense training without breaks, mountain climbing or hiking, and traveling when your body hasn’t had time to acclimate gradually to high altitudes
Avoid or talk to your doctor about activities that involve changes in atmospheric pressure like scuba diving
What Happens Next With the SCT Study?
The study results will be peer-reviewed by other sickle cell and renal medullary carcinoma experts before publication in a medical journal. It’s very important to note that light-intensity exercise and moderate-intensity exercise are not shown to be risk factors for RMC. If you have concerns about what is considered high-intensity exercise, make sure to talk to your doctor about your concerns or contact one of the experts featured in our Sickle Cell Provider Directory who are committed to working toward optimal health outcomes.
In retaining editorial control, the information produced by Diverse Health Hub does not encapsulate the views of our sponsors, contributors, or collaborators.
Importantly, this information is not a substitute for, nor does it replace professional medical advice, diagnosis, or treatment. If you have any concerns or questions about your health, you should always consult with a healthcare professional.
Sources
Msaouel, P., et al. Updated Recommendations on the Diagnosis, Management, and Clinical Trial Eligibility Criteria for Patients With Renal Medullary Carcinoma. Clin Genitourin Cancer 17, 1–6 (2019).
Daniel D. Shapiro, Melinda Soeung, Luigi Perelli, Eleonora Dondossola, Devaki Shilpa Surasi, Durga N. Tripathi, Jean-Philippe Bertocchio, Ruohan Xia, Michael W. Starbuck, Michael L. Van Alstine, Priya Rao, Matthew H. G. Katz, Nathan H. Parker, Amishi Y. Shah, Alessandro Carugo, Timothy P. Heffernan, Keri L. Schadler, Christopher Logothetis, Cheryl L. Walker, Christopher G. Wood, Jose A. Karam, Giulio F. Draetta, Nizar M. Tannir, Giannicola Genovese, Pavlos Msaouel. High-intensity exercise is a risk factor for renal medullary carcinoma in individuals with sickle cell trait. medRxiv. https://doi.org/10.1101/2021.02.23.21252313
What is Sickle Cell Trait? Centers for Disease Control and Prevention. Last reviewed December 14, 2020. https://www.cdc.gov/ncbddd/sicklecell/traits.html
Meredith Wadman. Sickle-cell mystery solved. Nature. November 10, 2011.https://www.nature.com/news/sickle-cell-mystery-solved-1.9342
