Individuals suffering from gender dysphoria may decide to take hormone therapy, but a new study says that this treatment can increase the risk of serious cardiac events

As part of gender affirmation treatment, people with gender dysphoria may start hormone replacement therapy. Naturally, this is a very significant event in a person’s life- but researchers warn that it is not a risk-free endeavour.

This is because, according to a study presented at the American College of Cardiology’s Annual Scientific Session Together With the World Congress of Cardiology, individuals who seek hormone therapy face increased cardiovascular risks, including stroke, heart attack and pulmonary embolism.

What is gender dysphoria?

Gender dysphoria is when a person’s gender assigned at birth does not align with their gender identity.

Gender affirmation therapy, the process more commonly referred to as transitioning, includes a variety of medical, psychological and behavioural interventions to help individuals feel more comfortable in their gender identity.

This may include hormone therapy which allows them to acquire secondary sex characteristics that align with their gender identity.

Between 1 million to 1.6 million people identify as transgender in the U.S., and hormone therapy use is also on the rise, especially among teens and young adults.

Investigating the cardiovascular risks of hormone therapy

Exploring the side effects and risks of gender affirmation therapy is historically understudied. This is, in fact, the largest study of its kind.

Previous research has looked at younger women using hormone-based birth control or older women following a hysterectomy or during menopause. In these populations, long-term hormone replacement therapy has been associated with an increased risk of breast cancer, stroke and blood clots.

Researchers retrospectively examined rates of cardiovascular events in over 21,000 people with gender dysphoria from a national database of hospital records. Of these 21,000 people, 1,675 had used hormone replacement therapy.

Generally speaking, individuals assigned male at birth receive estrogen, and those assigned female at birth receive testosterone.

What are the associated risks of hormone therapy?

The study revealed that hormone replacements were associated with higher rates of cardiac events, and this was mostly related to dangerous blood clots. However, higher death rates were not found.

‘Starting transitioning is a big part of a person’s life and helping them feel more themselves, but hormone replacement therapy also has a lot of side effects’

“It’s all about risks and benefits. Starting transitioning is a big part of a person’s life and helping them feel more themselves, but hormone replacement therapy also has a lot of side effects—it’s not a risk-free endeavor,” explained Ibrahim Ahmed, MD, a third-year resident at Mercy Catholic Medical Center in Darby, Pennsylvania and the study’s lead author.

To illustrate, people with gender dysphoria and who had used hormone replacement therapy at some point in their lifetime saw nearly seven times the risk of ischemic stroke (a blockage in a vessel supplying blood to the brain), nearly six times the risk of ST-elevation myocardial infarction (the most serious type of heart attack) and nearly five times the risk of pulmonary embolism (a blockage in an artery in the lung), compared with people with gender dysphoria who had never used hormone replacements.

Hormone replacement therapy was not associated with increased deaths from any cause or with increased rates of atrial fibrillation, diabetes, hypertension, hemorrhagic stroke or heart failure.

It is well-known that estrogen and testosterone increase the clotting activity of blood, and this may explain the increase in clotting-related cardiovascular events, researchers said. Individuals on hormone replacement therapy also had higher rates of substance use disorder and hypothyroidism.

Medical and family history must be examined before beginning HRT

“Looking at a person’s medical and family history should definitely be part of the screening protocol before they even start hormone replacement therapy,” Ahmed said. “It is also important that people considering this therapy are made aware of all the risks.”

It is worth considering the limitations of the study. One is that it only accounted for whether individuals had ever used any type of hormone replacement therapy.

In the future, researchers agreed that to make better informed clinical decisions, it would be helpful to assess whether the duration of treatment, the age at which it is initiated or the type of hormone therapy used affects the risks.

‘I’m curious to see if the method of administration alters the outcomes’

“I’m curious to see if the method of administration alters the outcomes,” Ahmed concluded. “Is one way of giving hormone replacement therapy better or associated with a lower risk of cardiovascular outcomes? If so, then that should be the focus for how we give these patients their hormone replacement therapy going forward.”

As well as exploring ways to mitigate potential cardiovascular risks before starting hormone replacement therapy for individual patients, researchers said they must continue studying the potential long-term cardiovascular and other health effects of gender affirmation therapies as these therapies become more and more common.


Please enter your comment!
Please enter your name here