BIRMINGHAM, United Kingdom — Athletes, entertainers, and bodybuilders have used anabolic steroids for decades to build up levels of muscle mass that just wouldn’t be possible by simply eating right and working out often. While the use of such substances has long been associated with health issues, particularly of the cardiovascular variety, new research from the University of Birmingham is adding yet another reason to take an all-natural approach to fitness: heart health.
Scientists say that among individuals with an existing predisposition, taking testosterone may increase the risk of atrial fibrillation, or an irregular heartbeat. An interdisciplinary consortium of clinicians and researchers led by the University of Birmingham, in addition to a team of collaborators in Germany, conducted this project.
The research team uncovered that male sex hormones (like testosterone), also referred to as androgenic anabolic steroids (AAS), appear capable of increasing the risk of atrial fibrillation in individuals genetically predisposed to heart disease. Steroids are frequently abused to build large muscles, especially among young men.
“Our study can significantly contribute to understanding the impact on the heart health of young men who misuse anabolic steroids to increase muscle mass. Recent reports have shown that young men in particular are being targeted on social media such as TikTok being sold testosterone products, but we have shown how the misuse of steroids carries a specific risk that many people will not be aware of,” says lead study author Dr. Laura Sommerfeld, Postdoctoral Researcher at the UKE Hamburg, who completed her PhD at the Institute of Cardiovascular Sciences at the University of Birmingham focusing on this work, in a media release.
“Heart muscle diseases like ARVC affect young, athletic individuals and can lead to life-threatening heart rhythm disturbances. Atrial fibrillation is a common condition in the general population. Elevated testosterone levels can result in an earlier onset of these diseases,” adds Professor Larissa Fabritz, Chair of Inherited Cardiac Conditions at UKE Hamburg and Honorary Chair in the Institute of Cardiovascular Sciences at the University of Birmingham.
Study authors worked to examine any and all potential effects on a condition called arrhythmogenic right ventricular cardiomyopathy (ARVC), which is primarily attributed to disruptions in the formation of cell connections critical to the stability of heart muscles.
Initially, based on clinical patient data from UHB and elsewhere, researchers confirmed that ARVC tends to occur more frequently and severely in men than in women. Across a series of lab experiments, study authors discovered that six weeks of AAS intake in combination with impaired cell connections could potentially lead to reduced sodium channel functioning in heart tissue and a subsequent slowing of signal conduction inside the atria.
“This work implies that young male individuals with key inherited genetic changes have a greater risk of developing electrical problems in the heart in response to anabolic steroid abuse,” Dr. Andrew Holmes, co-author and Assistant Professor in the Institute of Clinical Sciences at the University of Birmingham, concludes.
The study is published in The Journal of Physiology.