Men who use testosterone replacement therapy have a 63 percent increased risk of having a blood clot-related heart attack, stroke, organ damage or death within the first six months of treatment, a new study has found.
“Risk peaks rapidly in the first six months of treatment and lasts for about nine months, and fades gradually thereafter,” said Dr. Carlos Martinez with the Institute for Epidemiology, Statistics and Informatics in Frankfurt, Germany. Martinez is the lead author of the study, which was published in the British Medical Journal.
Testosterone treatments are used by millions of men. The hormone replacements are intended for men with hypogonadism, a condition in which the testes do not produce enough of the male hormone due to injury, disease or defect, resulting in symptoms such as low libido, infertility and muscle wasting.
Aggressive marketing campaigns by manufacturers of testosterone treatments – promising to treat low sex drive and improve mood – have resulted in skyrocketing prescriptions and sales in the U.S., raising concerns that the drugs may be overprescribed. Earlier this year, the Food and Drug Administration (FDA) warned that testosterone supplements are abused by adolescents and adults, especially body builders and athletes. The agency also warned that use of the products has been linked to cardiac and mental health problems.
Previous studies have linked testosterone treatments to an increased risk of heart attacks, strokes, blood clots and death. The latest study involved more than 2.2 million men and evaluated the incidence of blood clots in the veins, a condition known as venous thromboembolism (VTE). Researchers concluded that men starting testosterone treatment were at greatest risk of developing these blood clots compared to men who did not use the drugs or who had been using them for more than six months.
Researchers say that more studies are needed to better understand the long-term effects of testosterone treatments.