A new study has revealed that individuals with gender dysphoria taking hormone replacements as part of gender affirmation therapy face a ‘substantially increased’ risk of stroke, among other serious cardiac conditions.
Gender dysphoria happens when a person’s gender identity, part of a process known as transitioning, includes a variety of medical, psychological and behavioural interventions to help individuals, many of whom identify as transgender, acquire secondary sex characteristics that align with their gender identity.
Recent data suggest about 1 million to 1.6 individuals identify as transgender in the United States and that hormone therapy use is rising rapidly, especially among teens and young adults.
This study is the largest to date examining the cardiovascular risks of gender affirmation therapy in what is an historically understudied population.
Previous research on hormone-modulating medications has primarily focused on younger women using hormone-based birth control or on older women following a hysterectomy or during menopause. In these populations, long-term hormone replacement therapy. Has been associated with an increased risk of stroke, as well as cancer.
Researchers on this study examined rates of cardiovascular events in over 21,000 individuals with gender dysphoria from a national database of hospital records, of whom 1,675 had used hormone replacement therapy.
It is typical that those assigned male at birth receive oestrogen and those assigned female at birth receive testosterone.
The overall results found that hormone replacements were associated with higher rates of cardiac events, mostly related to dangerous blood clots, however, they were not associated with higher rates of death.
Ibrahim Ahmed, study lead author, says: “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 endeavour.”
In the study, people with gender dysphoria who had ever used hormone replacements saw nearly seven times the risk ischaemic stroke, compared to individuals with gender dysphoria who had never used hormone replacements.
Hormone replacement therapy was not associated with any increase in deaths from any cause or with increased rates of atrial fibrillation, diabetes, hypertension, haemorrhagic stroke or heart failure.
Both oestrogen and testosterone are known to increase clotting activity of blood, which is a possible explanation to the increase in clotting-related cardiovascular events, according to the researchers.
Ahmed says: “Looking at a person’s medical and family history should definitely be part of the screening protocol before they even start hormone replacement therapy.
“It is also important that people considering this therapy are made aware of all the risks.”
A limitation of this study is that it only accounted for whether individuals had ever used any type of hormone replacement therapy. In order to better inform clinical decisions, researchers say 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.
Ahmed, says: “I’m curious to see if the method of administration alters the outcomes.
“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.”
Researchers also state that it will be important to continue to study potential long-term cardiovascular and other health effects of gender affirmation therapies as the use of these therapies become more common.
